test(ruff_python_formatter): Run all Black tests (#2993)

This PR changes the testing infrastructure to run all black tests and:

* Pass if Ruff and Black generate the same formatting
* Fail and write a markdown snapshot that shows the input code, the differences between Black and Ruff, Ruffs output, and Blacks output

This is achieved by introducing a new `fixture` macro (open to better name suggestions) that "duplicates" the attributed test for every file that matches the specified glob pattern. Creating a new test for each file over having a test that iterates over all files has the advantage that you can run a single test, and that test failures indicate which case is failing. 

The `fixture` macro also makes it straightforward to e.g. setup our own spec tests that test very specific formatting by creating a new folder and use insta to assert the formatted output.

Cargo.lock

@@ -2075,13 +2075,26 @@ dependencies = [
  "insta",
  "once_cell",
  "ruff_formatter",
+ "ruff_testing_macros",
  "ruff_text_size",
  "rustc-hash",
  "rustpython-common",
  "rustpython-parser",
+ "similar",
  "test-case",
 ]
 
+[[package]]
+name = "ruff_testing_macros"
+version = "0.0.0"
+dependencies = [
+ "glob",
+ "proc-macro-error",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "ruff_text_size"
 version = "0.0.0"

crates/ruff_python_formatter/Cargo.toml

@@ -18,3 +18,5 @@ rustpython-parser = { workspace = true }
 [dev-dependencies]
 insta = { version = "1.19.0", features = [] }
 test-case = { version = "2.2.2" }
+ruff_testing_macros = { path = "../ruff_testing_macros" }
+similar = "2.2.1"

crates/ruff_python_formatter/resources/test/fixtures/black/.editorconfig

@@ -0,0 +1,6 @@
+# Check http://editorconfig.org for more information
+# This is the main config file for this project:
+root = true
+
+[*.py.expect]
+insert_final_newline = false

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/attribute_access_on_number_literals.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 x = (123456789).bit_count()
 x = (123456).__abs__()
 x = (0.1).is_integer()
@@ -25,4 +20,3 @@ if (10).real:
 
 y = 100[no]
 y = 100(no)
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/beginning_backslash.py.expect

@@ -0,0 +1 @@
+print("hello, world")

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/bracketmatch.py.expect

@@ -0,0 +1,4 @@
+for ((x in {}) or {})["a"] in x:
+    pass
+pem_spam = lambda l, spam={"x": 3}: not spam.get(l.strip())
+lambda x=lambda y={1: 3}: y["x" : lambda y: {1: 2}]: x

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/class_blank_parentheses.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 class SimpleClassWithBlankParentheses:
     pass
 
@@ -33,4 +28,3 @@ class NormalClass:
     def func_for_testing(self, first, second):
         sum = first + second
         return sum
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/class_methods_new_line.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 class ClassSimplest:
     pass
 
@@ -168,4 +163,3 @@ class ClassWithDecoInitAndVarsAndDocstringWithInner2:
     @deco
     def __init__(self):
         pass
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/collections.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 import core, time, a
 
 from . import A, B, C
@@ -102,4 +97,3 @@ if True:
             "Delay": 5,
         },
     )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comment_after_escaped_newline.py.expect

@@ -0,0 +1,6 @@
+def bob():  # pylint: disable=W9016
+    pass
+
+
+def bobtwo():  # some comment here
+    pass

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 #!/usr/bin/env python3
 # fmt: on
 # Some license here.
@@ -99,4 +94,3 @@ async def wat():
 # Some closing comments.
 # Maybe Vim or Emacs directives for formatting.
 # Who knows.
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments2.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
     MyLovelyCompanyTeamProjectComponent,  # NOT DRY
 )
@@ -176,4 +171,3 @@ instruction()  # comment with bad spacing
 
 # END COMMENTS
 # MORE END COMMENTS
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments3.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # The percent-percent comments are Spyder IDE cells.
 
 
@@ -51,4 +46,3 @@ def func():
 
 
 # %%
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments4.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
     MyLovelyCompanyTeamProjectComponent,  # NOT DRY
 )
@@ -97,4 +92,3 @@ def foo3(list_a, list_b):
         )
         .filter(User.xyz.is_(None))
     )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments5.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 while True:
     if something.changed:
         do.stuff()  # trailing comment
@@ -76,4 +71,3 @@ def g():
 
 if __name__ == "__main__":
     main()
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments6.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 from typing import Any, Tuple
 
 
@@ -121,4 +116,3 @@ call_to_some_function_asdf(
 )
 
 aaaaaaaaaaaaa, bbbbbbbbb = map(list, map(itertools.chain.from_iterable, zip(*items)))  # type: ignore[arg-type]
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments8.py.expect

@@ -1,12 +1,6 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # The percent-percent comments are Spyder IDE cells.
 # Both `#%%`` and `# %%` are accepted, so `black` standardises
 # to the latter.
 
 # %%
 # %%
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments9.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # Test for https://github.com/psf/black/issues/246.
 
 some = statement
@@ -164,4 +159,3 @@ def foo():
 # A standalone comment
 def bar():
     pass
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments_non_breaking_space.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 from .config import (
     ConfigTypeAttributes,
     Int,
@@ -26,4 +21,3 @@ def function(a: int = 42):
     #    There's a NBSP + 3 spaces before
     #    And 4 spaces on the next line
     pass
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/composition.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 class C:
     def test(self) -> None:
         with patch("black.out", print):
@@ -184,4 +179,3 @@ class C:
                 key9: value9,
             }
         )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/composition_no_trailing_comma.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 class C:
     def test(self) -> None:
         with patch("black.out", print):
@@ -184,4 +179,3 @@ class C:
                 key9: value9,
             }
         )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/docstring.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 class MyClass:
     """Multiline
     class docstring
@@ -222,4 +217,3 @@ def stable_quote_normalization_with_immediate_inner_single_quote(self):
 
     <text here, since without another non-empty line black is stable>
     """
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/docstring_no_extra_empty_line_before_eof.py.expect

@@ -1,10 +1,4 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # Make sure when the file ends with class's docstring,
 # It doesn't add extra blank lines.
 class ClassWithDocstring:
     """A docstring."""
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/docstring_preview.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 def docstring_almost_at_line_limit():
     """long docstring................................................................."""
 
@@ -51,4 +46,3 @@ def single_quote_docstring_over_line_limit():
 
 def single_quote_docstring_over_line_limit2():
     "We do not want to put the closing quote on a new line as that is invalid (see GH-3141)."
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/empty_lines.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 """Docstring."""
 
 
@@ -92,4 +87,3 @@ def g():
                 syms.argument,
             }:
                 return NO
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/expression.diff

@@ -1,466 +0,0 @@
---- [Deterministic header]
-+++ [Deterministic header]
-@@ -1,8 +1,8 @@
- ...
--'some_string'
--b'\\xa3'
-+"some_string"
-+b"\\xa3"
- Name
- None
- True
- False
- 1
-@@ -21,99 +21,135 @@
- Name1 or (Name2 and Name3) or Name4
- Name1 or Name2 and Name3 or Name4
- v1 << 2
- 1 >> v2
- 1 % finished
--1 + v2 - v3 * 4 ^ 5 ** v6 / 7 // 8
--((1 + v2) - (v3 * 4)) ^ (((5 ** v6) / 7) // 8)
-+1 + v2 - v3 * 4 ^ 5**v6 / 7 // 8
-+((1 + v2) - (v3 * 4)) ^ (((5**v6) / 7) // 8)
- not great
- ~great
- +value
- -1
- ~int and not v1 ^ 123 + v2 | True
- (~int) and (not ((v1 ^ (123 + v2)) | True))
--+really ** -confusing ** ~operator ** -precedence
--flags & ~ select.EPOLLIN and waiters.write_task is not None
-++(really ** -(confusing ** ~(operator**-precedence)))
-+flags & ~select.EPOLLIN and waiters.write_task is not None
- lambda arg: None
- lambda a=True: a
- lambda a, b, c=True: a
--lambda a, b, c=True, *, d=(1 << v2), e='str': a
--lambda a, b, c=True, *vararg, d=(v1 << 2), e='str', **kwargs: a + b
-+lambda a, b, c=True, *, d=(1 << v2), e="str": a
-+lambda a, b, c=True, *vararg, d=(v1 << 2), e="str", **kwargs: a + b
- manylambdas = lambda x=lambda y=lambda z=1: z: y(): x()
--foo = (lambda port_id, ignore_missing: {"port1": port1_resource, "port2": port2_resource}[port_id])
-+foo = lambda port_id, ignore_missing: {
-+    "port1": port1_resource,
-+    "port2": port2_resource,
-+}[port_id]
- 1 if True else 2
- str or None if True else str or bytes or None
- (str or None) if True else (str or bytes or None)
- str or None if (1 if True else 2) else str or bytes or None
- (str or None) if (1 if True else 2) else (str or bytes or None)
--((super_long_variable_name or None) if (1 if super_long_test_name else 2) else (str or bytes or None))
--{'2.7': dead, '3.7': (long_live or die_hard)}
--{'2.7': dead, '3.7': (long_live or die_hard), **{'3.6': verygood}}
-+(
-+    (super_long_variable_name or None)
-+    if (1 if super_long_test_name else 2)
-+    else (str or bytes or None)
-+)
-+{"2.7": dead, "3.7": (long_live or die_hard)}
-+{"2.7": dead, "3.7": (long_live or die_hard), **{"3.6": verygood}}
- {**a, **b, **c}
--{'2.7', '3.6', '3.7', '3.8', '3.9', ('4.0' if gilectomy else '3.10')}
--({'a': 'b'}, (True or False), (+value), 'string', b'bytes') or None
-+{"2.7", "3.6", "3.7", "3.8", "3.9", ("4.0" if gilectomy else "3.10")}
-+({"a": "b"}, (True or False), (+value), "string", b"bytes") or None
- ()
- (1,)
- (1, 2)
- (1, 2, 3)
- []
- [1, 2, 3, 4, 5, 6, 7, 8, 9, (10 or A), (11 or B), (12 or C)]
--[1, 2, 3,]
-+[
-+    1,
-+    2,
-+    3,
-+]
- [*a]
- [*range(10)]
--[*a, 4, 5,]
--[4, *a, 5,]
--[this_is_a_very_long_variable_which_will_force_a_delimiter_split, element, another, *more]
-+[
-+    *a,
-+    4,
-+    5,
-+]
-+[
-+    4,
-+    *a,
-+    5,
-+]
-+[
-+    this_is_a_very_long_variable_which_will_force_a_delimiter_split,
-+    element,
-+    another,
-+    *more,
-+]
- {i for i in (1, 2, 3)}
--{(i ** 2) for i in (1, 2, 3)}
--{(i ** 2) for i, _ in ((1, 'a'), (2, 'b'), (3, 'c'))}
--{((i ** 2) + j) for i in (1, 2, 3) for j in (1, 2, 3)}
-+{(i**2) for i in (1, 2, 3)}
-+{(i**2) for i, _ in ((1, "a"), (2, "b"), (3, "c"))}
-+{((i**2) + j) for i in (1, 2, 3) for j in (1, 2, 3)}
- [i for i in (1, 2, 3)]
--[(i ** 2) for i in (1, 2, 3)]
--[(i ** 2) for i, _ in ((1, 'a'), (2, 'b'), (3, 'c'))]
--[((i ** 2) + j) for i in (1, 2, 3) for j in (1, 2, 3)]
-+[(i**2) for i in (1, 2, 3)]
-+[(i**2) for i, _ in ((1, "a"), (2, "b"), (3, "c"))]
-+[((i**2) + j) for i in (1, 2, 3) for j in (1, 2, 3)]
- {i: 0 for i in (1, 2, 3)}
--{i: j for i, j in ((1, 'a'), (2, 'b'), (3, 'c'))}
-+{i: j for i, j in ((1, "a"), (2, "b"), (3, "c"))}
- {a: b * 2 for a, b in dictionary.items()}
- {a: b * -2 for a, b in dictionary.items()}
--{k: v for k, v in this_is_a_very_long_variable_which_will_cause_a_trailing_comma_which_breaks_the_comprehension}
-+{
-+    k: v
-+    for k, v in this_is_a_very_long_variable_which_will_cause_a_trailing_comma_which_breaks_the_comprehension
-+}
- Python3 > Python2 > COBOL
- Life is Life
- call()
- call(arg)
--call(kwarg='hey')
--call(arg, kwarg='hey')
--call(arg, another, kwarg='hey', **kwargs)
--call(this_is_a_very_long_variable_which_will_force_a_delimiter_split, arg, another, kwarg='hey', **kwargs)  # note: no trailing comma pre-3.6
-+call(kwarg="hey")
-+call(arg, kwarg="hey")
-+call(arg, another, kwarg="hey", **kwargs)
-+call(
-+    this_is_a_very_long_variable_which_will_force_a_delimiter_split,
-+    arg,
-+    another,
-+    kwarg="hey",
-+    **kwargs
-+)  # note: no trailing comma pre-3.6
- call(*gidgets[:2])
- call(a, *gidgets[:2])
- call(**self.screen_kwargs)
- call(b, **self.screen_kwargs)
- lukasz.langa.pl
- call.me(maybe)
--1 .real
--1.0 .real
-+(1).real
-+(1.0).real
- ....__class__
- list[str]
- dict[str, int]
- tuple[str, ...]
-+tuple[str, int, float, dict[str, int]]
- tuple[
--    str, int, float, dict[str, int]
--]
--tuple[str, int, float, dict[str, int],]
-+    str,
-+    int,
-+    float,
-+    dict[str, int],
-+]
- very_long_variable_name_filters: t.List[
-     t.Tuple[str, t.Union[str, t.List[t.Optional[str]]]],
- ]
- xxxx_xxxxx_xxxx_xxx: Callable[..., List[SomeClass]] = classmethod(  # type: ignore
-     sync(async_xxxx_xxx_xxxx_xxxxx_xxxx_xxx.__func__)
- )
- xxxx_xxx_xxxx_xxxxx_xxxx_xxx: Callable[..., List[SomeClass]] = classmethod(  # type: ignore
-     sync(async_xxxx_xxx_xxxx_xxxxx_xxxx_xxx.__func__)
- )
--xxxx_xxx_xxxx_xxxxx_xxxx_xxx: Callable[
--    ..., List[SomeClass]
--] = classmethod(sync(async_xxxx_xxx_xxxx_xxxxx_xxxx_xxx.__func__))  # type: ignore
-+xxxx_xxx_xxxx_xxxxx_xxxx_xxx: Callable[..., List[SomeClass]] = classmethod(
-+    sync(async_xxxx_xxx_xxxx_xxxxx_xxxx_xxx.__func__)
-+)  # type: ignore
- slice[0]
- slice[0:1]
- slice[0:1:2]
- slice[:]
- slice[:-1]
-@@ -137,118 +173,199 @@
- numpy[-(c + 1) :, d]
- numpy[:, l[-2]]
- numpy[:, ::-1]
- numpy[np.newaxis, :]
- (str or None) if (sys.version_info[0] > (3,)) else (str or bytes or None)
--{'2.7': dead, '3.7': long_live or die_hard}
--{'2.7', '3.6', '3.7', '3.8', '3.9', '4.0' if gilectomy else '3.10'}
-+{"2.7": dead, "3.7": long_live or die_hard}
-+{"2.7", "3.6", "3.7", "3.8", "3.9", "4.0" if gilectomy else "3.10"}
- [1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or A, 11 or B, 12 or C]
- (SomeName)
- SomeName
- (Good, Bad, Ugly)
- (i for i in (1, 2, 3))
--((i ** 2) for i in (1, 2, 3))
--((i ** 2) for i, _ in ((1, 'a'), (2, 'b'), (3, 'c')))
--(((i ** 2) + j) for i in (1, 2, 3) for j in (1, 2, 3))
-+((i**2) for i in (1, 2, 3))
-+((i**2) for i, _ in ((1, "a"), (2, "b"), (3, "c")))
-+(((i**2) + j) for i in (1, 2, 3) for j in (1, 2, 3))
- (*starred,)
--{"id": "1","type": "type","started_at": now(),"ended_at": now() + timedelta(days=10),"priority": 1,"import_session_id": 1,**kwargs}
-+{
-+    "id": "1",
-+    "type": "type",
-+    "started_at": now(),
-+    "ended_at": now() + timedelta(days=10),
-+    "priority": 1,
-+    "import_session_id": 1,
-+    **kwargs,
-+}
- a = (1,)
--b = 1,
-+b = (1,)
- c = 1
- d = (1,) + a + (2,)
- e = (1,).count(1)
- f = 1, *range(10)
- g = 1, *"ten"
--what_is_up_with_those_new_coord_names = (coord_names + set(vars_to_create)) + set(vars_to_remove)
--what_is_up_with_those_new_coord_names = (coord_names | set(vars_to_create)) - set(vars_to_remove)
--result = session.query(models.Customer.id).filter(models.Customer.account_id == account_id, models.Customer.email == email_address).order_by(models.Customer.id.asc()).all()
--result = session.query(models.Customer.id).filter(models.Customer.account_id == account_id, models.Customer.email == email_address).order_by(models.Customer.id.asc(),).all()
-+what_is_up_with_those_new_coord_names = (coord_names + set(vars_to_create)) + set(
-+    vars_to_remove
-+)
-+what_is_up_with_those_new_coord_names = (coord_names | set(vars_to_create)) - set(
-+    vars_to_remove
-+)
-+result = (
-+    session.query(models.Customer.id)
-+    .filter(
-+        models.Customer.account_id == account_id, models.Customer.email == email_address
-+    )
-+    .order_by(models.Customer.id.asc())
-+    .all()
-+)
-+result = (
-+    session.query(models.Customer.id)
-+    .filter(
-+        models.Customer.account_id == account_id, models.Customer.email == email_address
-+    )
-+    .order_by(
-+        models.Customer.id.asc(),
-+    )
-+    .all()
-+)
- Ø = set()
- authors.łukasz.say_thanks()
- mapping = {
-     A: 0.25 * (10.0 / 12),
-     B: 0.1 * (10.0 / 12),
-     C: 0.1 * (10.0 / 12),
-     D: 0.1 * (10.0 / 12),
- }
- 
-+
- def gen():
-     yield from outside_of_generator
--    a = (yield)
--    b = ((yield))
--    c = (((yield)))
-+    a = yield
-+    b = yield
-+    c = yield
-+
- 
- async def f():
-     await some.complicated[0].call(with_args=(True or (1 is not 1)))
--print(* [] or [1])
-+
-+
-+print(*[] or [1])
- print(**{1: 3} if False else {x: x for x in range(3)})
--print(* lambda x: x)
--assert(not Test),("Short message")
--assert this is ComplexTest and not requirements.fit_in_a_single_line(force=False), "Short message"
--assert(((parens is TooMany)))
--for x, in (1,), (2,), (3,): ...
--for y in (): ...
--for z in (i for i in (1, 2, 3)): ...
--for i in (call()): ...
--for j in (1 + (2 + 3)): ...
--while(this and that): ...
--for addr_family, addr_type, addr_proto, addr_canonname, addr_sockaddr in socket.getaddrinfo('google.com', 'http'):
-+print(*lambda x: x)
-+assert not Test, "Short message"
-+assert this is ComplexTest and not requirements.fit_in_a_single_line(
-+    force=False
-+), "Short message"
-+assert parens is TooMany
-+for (x,) in (1,), (2,), (3,):
-+    ...
-+for y in ():
-+    ...
-+for z in (i for i in (1, 2, 3)):
-+    ...
-+for i in call():
-+    ...
-+for j in 1 + (2 + 3):
-+    ...
-+while this and that:
-+    ...
-+for (
-+    addr_family,
-+    addr_type,
-+    addr_proto,
-+    addr_canonname,
-+    addr_sockaddr,
-+) in socket.getaddrinfo("google.com", "http"):
-     pass
--a = aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp in qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
--a = aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp not in qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
--a = aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp is qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
--a = aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp is not qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
--if (
--    threading.current_thread() != threading.main_thread() and
--    threading.current_thread() != threading.main_thread() or
--    signal.getsignal(signal.SIGINT) != signal.default_int_handler
--):
--    return True
--if (
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa |
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
--):
--    return True
--if (
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa &
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
--):
--    return True
--if (
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa +
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
--):
--    return True
--if (
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa -
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
--):
--    return True
--if (
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa *
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
--):
--    return True
--if (
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa /
--    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
--):
--    return True
--if (
--    ~ aaaa.a + aaaa.b - aaaa.c * aaaa.d / aaaa.e | aaaa.f & aaaa.g % aaaa.h ^ aaaa.i << aaaa.k >> aaaa.l ** aaaa.m // aaaa.n
--):
--    return True
--if (
--    ~ aaaaaaaa.a + aaaaaaaa.b - aaaaaaaa.c @ aaaaaaaa.d / aaaaaaaa.e | aaaaaaaa.f & aaaaaaaa.g % aaaaaaaa.h ^ aaaaaaaa.i << aaaaaaaa.k >> aaaaaaaa.l ** aaaaaaaa.m // aaaaaaaa.n
--):
--    return True
--if (
--    ~ aaaaaaaaaaaaaaaa.a + aaaaaaaaaaaaaaaa.b - aaaaaaaaaaaaaaaa.c * aaaaaaaaaaaaaaaa.d @ aaaaaaaaaaaaaaaa.e | aaaaaaaaaaaaaaaa.f & aaaaaaaaaaaaaaaa.g % aaaaaaaaaaaaaaaa.h ^ aaaaaaaaaaaaaaaa.i << aaaaaaaaaaaaaaaa.k >> aaaaaaaaaaaaaaaa.l ** aaaaaaaaaaaaaaaa.m // aaaaaaaaaaaaaaaa.n
--):
--    return True
--aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa - aaaaaaaaaaaaaaaa * (aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa) / (aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa)
-+a = (
-+    aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp
-+    in qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
-+)
-+a = (
-+    aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp
-+    not in qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
-+)
-+a = (
-+    aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp
-+    is qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
-+)
-+a = (
-+    aaaa.bbbb.cccc.dddd.eeee.ffff.gggg.hhhh.iiii.jjjj.kkkk.llll.mmmm.nnnn.oooo.pppp
-+    is not qqqq.rrrr.ssss.tttt.uuuu.vvvv.xxxx.yyyy.zzzz
-+)
-+if (
-+    threading.current_thread() != threading.main_thread()
-+    and threading.current_thread() != threading.main_thread()
-+    or signal.getsignal(signal.SIGINT) != signal.default_int_handler
-+):
-+    return True
-+if (
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    | aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+):
-+    return True
-+if (
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    & aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+):
-+    return True
-+if (
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    + aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+):
-+    return True
-+if (
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    - aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+):
-+    return True
-+if (
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    * aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+):
-+    return True
-+if (
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    / aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+):
-+    return True
-+if (
-+    ~aaaa.a + aaaa.b - aaaa.c * aaaa.d / aaaa.e
-+    | aaaa.f & aaaa.g % aaaa.h ^ aaaa.i << aaaa.k >> aaaa.l**aaaa.m // aaaa.n
-+):
-+    return True
-+if (
-+    ~aaaaaaaa.a + aaaaaaaa.b - aaaaaaaa.c @ aaaaaaaa.d / aaaaaaaa.e
-+    | aaaaaaaa.f & aaaaaaaa.g % aaaaaaaa.h
-+    ^ aaaaaaaa.i << aaaaaaaa.k >> aaaaaaaa.l**aaaaaaaa.m // aaaaaaaa.n
-+):
-+    return True
-+if (
-+    ~aaaaaaaaaaaaaaaa.a
-+    + aaaaaaaaaaaaaaaa.b
-+    - aaaaaaaaaaaaaaaa.c * aaaaaaaaaaaaaaaa.d @ aaaaaaaaaaaaaaaa.e
-+    | aaaaaaaaaaaaaaaa.f & aaaaaaaaaaaaaaaa.g % aaaaaaaaaaaaaaaa.h
-+    ^ aaaaaaaaaaaaaaaa.i
-+    << aaaaaaaaaaaaaaaa.k
-+    >> aaaaaaaaaaaaaaaa.l**aaaaaaaaaaaaaaaa.m // aaaaaaaaaaaaaaaa.n
-+):
-+    return True
-+(
-+    aaaaaaaaaaaaaaaa
-+    + aaaaaaaaaaaaaaaa
-+    - aaaaaaaaaaaaaaaa
-+    * (aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa)
-+    / (aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa)
-+)
- aaaaaaaaaaaaaaaa + aaaaaaaaaaaaaaaa
--aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa >> aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+(
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    >> aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    << aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+)
- bbbb >> bbbb * bbbb
--aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa ^bbbb.a & aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa^aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+(
-+    aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    ^ bbbb.a & aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+    ^ aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa
-+)
- last_call()
- # standalone comment at ENDMARKER

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/expression.py.expect

@@ -1,9 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
-...
 "some_string"
 b"\\xa3"
 Name
@@ -374,4 +368,3 @@ bbbb >> bbbb * bbbb
 )
 last_call()
 # standalone comment at ENDMARKER
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 #!/usr/bin/env python3
 import asyncio
 import sys
@@ -227,4 +222,3 @@ yield  'hello'
 l=[1,2,3]
 d={'a':1,
    'b':2}
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff2.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 import pytest
 
 TmSt = 1
@@ -43,4 +38,3 @@ def test_calculate_fades():
     ]
 
 # fmt: on
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff3.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # fmt: off
 x = [
     1, 2,
@@ -18,4 +13,3 @@ x = [
 # fmt: on
 
 x = [1, 2, 3, 4]
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff4.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # fmt: off
 @test([
     1, 2,
@@ -23,4 +18,3 @@ def f():
 )
 def f():
     pass
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff5.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # Regression test for https://github.com/psf/black/issues/3129.
 setup(
     entry_points={
@@ -90,4 +85,3 @@ if x:
 elif   unformatted:
     # fmt: on
     will_be_formatted()
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip.py.expect

@@ -0,0 +1,3 @@
+a, b = 1, 2
+c =    6  # fmt: skip
+d = 5

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip2.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 l1 = [
     "This list should be broken up",
     "into multiple lines",
@@ -14,4 +9,3 @@ l3 = [
     "trailing comma",
     "so I should be braked",
 ]
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip3.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 a = 3
 # fmt: off
 b,    c = 1, 2
@@ -13,4 +8,3 @@ f = [
     "This is a very long line that should be formatted into a clearer line ",
     "by rearranging.",
 ]
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip4.py.expect

@@ -0,0 +1,7 @@
+a = 2
+# fmt: skip
+l = [
+    1,
+    2,
+    3,
+]

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip5.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 a, b, c = 3, 4, 5
 if (
     a == 3
@@ -12,4 +7,3 @@ if (
     print("I'm good!")
 else:
     print("I'm bad")
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip6.py.expect

@@ -0,0 +1,5 @@
+class A:
+    def f(self):
+        for line in range(10):
+            if True:
+                pass  # fmt: skip

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip7.py.expect

@@ -1,10 +1,4 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 a = "this is some code"
 b =     5  # fmt:skip
 c = 9  # fmt: skip
 d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  # fmt:skip
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip8.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # Make sure a leading comment is not removed.
 def some_func(  unformatted,  args  ):  # fmt: skip
     print("I am some_func")
@@ -65,4 +60,3 @@ with  give_me_context(  unformatted,  args  ):  # fmt: skip
 async def test_async_with():
     async  with  give_me_async_context(  unformatted,  args  ):  # fmt: skip
         print("Do something")
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fstring.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 f"f-string without formatted values is just a string"
 f"{{NOT a formatted value}}"
 f'{{NOT \'a\' "formatted" "value"}}'
@@ -12,4 +7,3 @@ f"{f'''{'nested'} inner'''} outer"
 f"\"{f'{nested} inner'}\" outer"
 f"space between opening braces: { {a for a in (1, 2, 3)}}"
 f'Hello \'{tricky + "example"}\''
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/function.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 #!/usr/bin/env python3
 import asyncio
 import sys
@@ -151,4 +146,3 @@ def f(
 
 def __await__():
     return (yield)
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/function2.py.expect

@@ -1,7 +1,3 @@
----
-source: crates/ruff_python_formatter/src/lib.rs
-expression: adjust_quotes(formatted.print()?.as_code())
----
 def f(
     a,
     **kwargs,
@@ -68,4 +64,3 @@ else:
 
 with hmm_but_this_should_get_two_preceding_newlines():
     pass
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/function_trailing_comma.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 def f(
     a,
 ):
@@ -117,4 +112,3 @@ some_module.some_function(
     argument5,
     argument6,
 )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/import_spacing.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 """The asyncio package, tracking PEP 3156."""
 
 # flake8: noqa
@@ -67,4 +62,3 @@ __all__ = (
     + streams.__all__
     + tasks.__all__
 )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/one_element_subscript.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # We should not treat the trailing comma
 # in a single-element subscript.
 a: tuple[int,]
@@ -25,4 +20,3 @@ small_list = [
 list_of_types = [
     tuple[int,],
 ]
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/power_op_spacing.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 def function(**kwargs):
     t = a**2 + b**3
     return t**2
@@ -66,4 +61,3 @@ if hasattr(view, "sum_of_weights"):
 return np.divide(
     where=view.sum_of_weights_of_weight_long**2 > view.sum_of_weights_squared,  # type: ignore
 )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/prefer_rhs_split_reformatted.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # Test cases separate from `prefer_rhs_split.py` that contains unformatted source.
 
 # Left hand side fits in a single line but will still be exploded by the
@@ -24,4 +19,3 @@ expression: formatted
 xxxxxxxxx_yyy_zzzzzzzz[
     xx.xxxxxx(x_yyy_zzzzzz.xxxxx[0]), x_yyy_zzzzzz.xxxxxx(xxxx=1)
 ] = 1
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/remove_await_parens.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 import asyncio
 
 
@@ -96,4 +91,3 @@ async def main():
 
 async def main():
     await (yield)
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/remove_except_parens.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # These brackets are redundant, therefore remove.
 try:
     a.something
@@ -45,4 +40,3 @@ except (
     some.really.really.really.looooooooooooooooooooooooooooooooong.module.over89.chars.Error,
 ) as err:
     raise err
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/remove_for_brackets.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # Only remove tuple brackets after `for`
 for k, v in d.items():
     print(k, v)
@@ -30,4 +25,3 @@ for (
 # Test deeply nested brackets
 for k, v in d.items():
     print(k, v)
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/remove_newline_after_code_block_open.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 import random
 
 
@@ -81,4 +76,3 @@ with open("/path/to/file.txt", mode="w") as file:
 with open("/path/to/file.txt", mode="r") as read_file:
     with open("/path/to/output_file.txt", mode="w") as write_file:
         write_file.writelines(read_file.readlines())
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/remove_parens.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 x = 1
 x = 1.2
 
@@ -88,4 +83,3 @@ def example7():
 
 def example8():
     return None
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/return_annotation_brackets.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # Control
 def double(a: int) -> int:
     return 2 * a
@@ -123,4 +118,3 @@ def foo() -> (
     ]
 ):
     return 2
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/skip_magic_trailing_comma.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 # We should not remove the trailing comma in a single-element subscript.
 a: tuple[int,]
 b = tuple[int,]
@@ -28,4 +23,3 @@ func1(arg1).func2(arg2).func3(arg3).func4(arg4).func5(arg5)
 (a, b, c, d) = func1(arg1) and func2(arg2)
 
 func(argument1, (one, two), argument4, argument5, argument6)
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/slices.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 slice[a.b : c.d]
 slice[d :: d + 1]
 slice[d + 1 :: d]

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/string_prefixes.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 #!/usr/bin/env python3
 
 name = "Łukasz"
@@ -23,4 +18,3 @@ def docstring_multiline():
     R"""
     clear out all of the issues opened in that time :p
     """
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/torture.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 importA
 (
     ()
@@ -61,4 +56,3 @@ assert a_function(
     very_long_arguments_that_surpass_the_limit,
     which_is_eighty_eight_in_this_case_plus_a_bit_more,
 ) == {"x": "this need to pass the line limit as well", "b": "but only by a little bit"}
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/trailing_comma_optional_parens1.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 if e1234123412341234.winerror not in (
     _winapi.ERROR_SEM_TIMEOUT,
     _winapi.ERROR_PIPE_BUSY,
@@ -37,4 +32,3 @@ class A:
             3,
         ) < self.connection.mysql_version < (10, 5, 2):
             pass
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/trailing_comma_optional_parens2.py.expect

@@ -1,12 +1,6 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 if e123456.get_tk_patchlevel() >= (8, 6, 0, "final") or (
     8,
     5,
     8,
 ) <= get_tk_patchlevel() < (8, 6):
     pass
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/trailing_comma_optional_parens3.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 if True:
     if True:
         if True:
@@ -11,4 +6,3 @@ if True:
                 + "qweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqwegqweasdzxcqweasdzxc.",
                 "qweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqweasdzxcqwe",
             ) % {"reported_username": reported_username, "report_reason": report_reason}
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/trailing_commas_in_leading_parts.py.expect

@@ -1,8 +1,3 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
 zero(
     one,
 ).two(
@@ -53,4 +48,3 @@ assert xxxxxxxxx.xxxxxxxxx.xxxxxxxxx(
 ).xxxxxxxxxxxxxxxxxx(), (
     "xxx {xxxxxxxxx} xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
 )
-

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/tricky_unicode_symbols.py.expect

@@ -0,0 +1,9 @@
+ä = 1
+µ = 2
+蟒 = 3
+x󠄀 = 4
+មុ = 1
+Q̇_per_meter = 4
+
+A᧚ = 3
+A፩ = 8

crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/tupleassign.py.expect

@@ -1,7 +1,3 @@
----
-source: crates/ruff_python_formatter/src/lib.rs
-expression: formatted.print()?.as_code()
----
 # This is a standalone comment.
 (
     sdfjklsdfsjldkflkjsf,

crates/ruff_python_formatter/src/lib.rs

@@ -20,8 +20,6 @@ mod format;
 mod newlines;
 mod parentheses;
 pub mod shared_traits;
-#[cfg(test)]
-mod test;
 pub mod trivia;
 
 pub fn fmt(contents: &str) -> Result<Formatted<ASTFormatContext>> {
@@ -57,70 +55,98 @@ pub fn fmt(contents: &str) -> Result<Formatted<ASTFormatContext>> {
 
 #[cfg(test)]
 mod tests {
+    use std::fs;
     use std::path::Path;
 
     use anyhow::Result;
-    use test_case::test_case;
 
     use crate::fmt;
-    use crate::test::test_resource_path;
+    use ruff_testing_macros::fixture;
+    use similar::TextDiff;
+    use std::fmt::{Formatter, Write};
+
+    #[fixture(
+        pattern = "resources/test/fixtures/black/**/*.py",
+        // Excluded tests because they reach unreachable when attaching tokens
+        exclude = [
+            "*comments.py",
+            "*comments[3,5,8].py",
+            "*comments_non_breaking_space.py",
+            "*docstring_preview.py",
+            "*docstring.py",
+            "*fmtonoff.py",
+            "*fmtskip8.py",
+        ])
+    ]
+    #[test]
+    fn black_test(input_path: &Path) -> Result<()> {
+        let content = fs::read_to_string(input_path)?;
 
-    #[test_case(Path::new("simple_cases/beginning_backslash.py"); "beginning_backslash")]
-    #[test_case(Path::new("simple_cases/class_blank_parentheses.py"); "class_blank_parentheses")]
-    #[test_case(Path::new("simple_cases/class_methods_new_line.py"); "class_methods_new_line")]
-    #[test_case(Path::new("simple_cases/import_spacing.py"); "import_spacing")]
-    #[test_case(Path::new("simple_cases/one_element_subscript.py"); "one_element_subscript")]
-    #[test_case(Path::new("simple_cases/power_op_spacing.py"); "power_op_spacing")]
-    #[test_case(Path::new("simple_cases/remove_newline_after_code_block_open.py"); "remove_newline_after_code_block_open")]
-    #[test_case(Path::new("simple_cases/slices.py"); "slices")]
-    #[test_case(Path::new("simple_cases/tricky_unicode_symbols.py"); "tricky_unicode_symbols")]
-    // Passing except that `1, 2, 3,` should be `(1, 2, 3)`.
-    #[test_case(Path::new("simple_cases/tupleassign.py"); "tupleassign")]
-    // Passing except that `CliRunner().invoke(...)` arguments are improperly wrapped.
-    #[test_case(Path::new("simple_cases/function2.py"); "function2")]
-    fn passing(path: &Path) -> Result<()> {
-        let snapshot = format!("{}", path.display());
-        let content = std::fs::read_to_string(test_resource_path(
-            Path::new("fixtures/black").join(path).as_path(),
-        ))?;
         let formatted = fmt(&content)?;
-        insta::assert_display_snapshot!(snapshot, formatted.print()?.as_code());
-        Ok(())
-    }
 
-    #[test_case(Path::new("simple_cases/collections.py"); "collections")]
+        let expected_path = input_path.with_extension("py.expect");
-    #[test_case(Path::new("simple_cases/bracketmatch.py"); "bracketmatch")]
+        let expected_output = fs::read_to_string(&expected_path)
-    fn passing_modulo_string_normalization(path: &Path) -> Result<()> {
+            .unwrap_or_else(|_| panic!("Expected Black output file '{expected_path:?}' to exist"));
-        fn adjust_quotes(contents: &str) -> String {
+
-            // Replace all single quotes with double quotes.
+        let printed = formatted.print()?;
-            contents.replace('\'', "\"")
+        let formatted_code = printed.as_code();
+
+        if formatted_code == expected_output {
+            // Black and Ruff formatting matches. Delete any existing snapshot files because the Black output
+            // already perfectly captures the expected output.
+            // The following code mimics insta's logic generating the snapshot name for a test.
+            let workspace_path = std::env::var("CARGO_MANIFEST_DIR").unwrap();
+            let snapshot_name = insta::_function_name!()
+                .strip_prefix(&format!("{}::", module_path!()))
+                .unwrap();
+            let module_path = module_path!().replace("::", "__");
+
+            let snapshot_path = Path::new(&workspace_path)
+                .join("src/snapshots")
+                .join(&format!(
+                    "{module_path}__{}.snap",
+                    snapshot_name.replace(&['/', '\\'][..], "__")
+                ));
+
+            if snapshot_path.exists() && snapshot_path.is_file() {
+                // SAFETY: This is a convenience feature. That's why we don't want to abort
+                // when deleting a no longer needed snapshot fails.
+                fs::remove_file(&snapshot_path).ok();
+            }
+
+            let new_snapshot_path = snapshot_path.with_extension("snap.new");
+            if new_snapshot_path.exists() && new_snapshot_path.is_file() {
+                // SAFETY: This is a convenience feature. That's why we don't want to abort
+                // when deleting a no longer needed snapshot fails.
+                fs::remove_file(&new_snapshot_path).ok();
+            }
+        } else {
+            // Black and Ruff have different formatting. Write out a snapshot that covers the differences
+            // today.
+            let mut snapshot = String::new();
+            write!(snapshot, "{}", Header::new("Input"))?;
+            write!(snapshot, "{}", CodeFrame::new("py", &content))?;
+
+            write!(snapshot, "{}", Header::new("Black Differences"))?;
+
+            let diff = TextDiff::from_lines(expected_output.as_str(), formatted_code)
+                .unified_diff()
+                .header("Black", "Ruff")
+                .to_string();
+
+            write!(snapshot, "{}", CodeFrame::new("diff", &diff))?;
+
+            write!(snapshot, "{}", Header::new("Ruff Output"))?;
+            write!(snapshot, "{}", CodeFrame::new("py", formatted_code))?;
+
+            write!(snapshot, "{}", Header::new("Black Output"))?;
+            write!(snapshot, "{}", CodeFrame::new("py", &expected_output))?;
+
+            insta::with_settings!({ omit_expression => false, input_file => input_path }, {
+                insta::assert_snapshot!(snapshot);
+            });
         }
 
-        let snapshot = format!("{}", path.display());
-        let content = std::fs::read_to_string(test_resource_path(
-            Path::new("fixtures/black").join(path).as_path(),
-        ))?;
-        let formatted = fmt(&content)?;
-        insta::assert_display_snapshot!(snapshot, adjust_quotes(formatted.print()?.as_code()));
-        Ok(())
-    }
-
-    #[ignore]
-    // Lots of deviations, _mostly_ related to string normalization and wrapping.
-    #[test_case(Path::new("simple_cases/expression.py"); "expression")]
-    // Passing apart from a trailing end-of-line comment within an if statement, which is being
-    // inappropriately associated with the if statement rather than the line it's on.
-    #[test_case(Path::new("simple_cases/comments.py"); "comments")]
-    #[test_case(Path::new("simple_cases/function.py"); "function")]
-    #[test_case(Path::new("simple_cases/function_trailing_comma.py"); "function_trailing_comma")]
-    #[test_case(Path::new("simple_cases/composition.py"); "composition")]
-    fn failing(path: &Path) -> Result<()> {
-        let snapshot = format!("{}", path.display());
-        let content = std::fs::read_to_string(test_resource_path(
-            Path::new("fixtures/black").join(path).as_path(),
-        ))?;
-        let formatted = fmt(&content)?;
-        insta::assert_display_snapshot!(snapshot, formatted.print()?.as_code());
         Ok(())
     }
 
@@ -150,4 +176,41 @@ mod tests {
 }"#
         );
     }
+
+    struct Header<'a> {
+        title: &'a str,
+    }
+
+    impl<'a> Header<'a> {
+        fn new(title: &'a str) -> Self {
+            Self { title }
+        }
+    }
+
+    impl std::fmt::Display for Header<'_> {
+        fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+            writeln!(f, "## {}", self.title)?;
+            writeln!(f)
+        }
+    }
+
+    struct CodeFrame<'a> {
+        language: &'a str,
+        code: &'a str,
+    }
+
+    impl<'a> CodeFrame<'a> {
+        fn new(language: &'a str, code: &'a str) -> Self {
+            Self { language, code }
+        }
+    }
+
+    impl std::fmt::Display for CodeFrame<'_> {
+        fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+            writeln!(f, "```{}", self.language)?;
+            writeln!(f, "{}", self.code)?;
+            writeln!(f, "```")?;
+            writeln!(f)
+        }
+    }
 }

crates/ruff_python_formatter/src/snapshots/expect/ruff_python_formatter__tests__simple_cases__comment_after_escaped_newline.py.snap.expect

@@ -1,12 +0,0 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
-def bob():  # pylint: disable=W9016
-    pass
-
-
-def bobtwo():  # some comment here
-    pass
-

crates/ruff_python_formatter/src/snapshots/expect/ruff_python_formatter__tests__simple_cases__fmtskip.py.snap.expect

@@ -1,9 +0,0 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
-a, b = 1, 2
-c =    6  # fmt: skip
-d = 5
-

crates/ruff_python_formatter/src/snapshots/expect/ruff_python_formatter__tests__simple_cases__fmtskip4.py.snap.expect

@@ -1,13 +0,0 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
-a = 2
-# fmt: skip
-l = [
-    1,
-    2,
-    3,
-]
-

crates/ruff_python_formatter/src/snapshots/expect/ruff_python_formatter__tests__simple_cases__fmtskip6.py.snap.expect

@@ -1,11 +0,0 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
-class A:
-    def f(self):
-        for line in range(10):
-            if True:
-                pass  # fmt: skip
-

crates/ruff_python_formatter/src/snapshots/expect/ruff_python_formatter__tests__simple_cases__whitespace.py.snap.expect

@@ -1,7 +0,0 @@
----
-source: src/source_code/mod.rs
-assertion_line: 0
-expression: formatted
----
-
-

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__attribute_access_on_number_literals_py.snap

@@ -0,0 +1,138 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/attribute_access_on_number_literals.py
+---
+## Input
+
+```py
+x = 123456789 .bit_count()
+x = (123456).__abs__()
+x = .1.is_integer()
+x = 1. .imag
+x = 1E+1.imag
+x = 1E-1.real
+x = 123456789.123456789.hex()
+x = 123456789.123456789E123456789 .real
+x = 123456789E123456789 .conjugate()
+x = 123456789J.real
+x = 123456789.123456789J.__add__(0b1011.bit_length())
+x = 0XB1ACC.conjugate()
+x = 0B1011 .conjugate()
+x = 0O777 .real
+x = 0.000000006  .hex()
+x = -100.0000J
+
+if 10 .real:
+    ...
+
+y = 100[no]
+y = 100(no)
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,22 +1,22 @@
+-x = (123456789).bit_count()
++x = 123456789.bit_count()
+ x = (123456).__abs__()
+-x = (0.1).is_integer()
+-x = (1.0).imag
+-x = (1e1).imag
+-x = (1e-1).real
+-x = (123456789.123456789).hex()
+-x = (123456789.123456789e123456789).real
+-x = (123456789e123456789).conjugate()
+-x = 123456789j.real
+-x = 123456789.123456789j.__add__(0b1011.bit_length())
+-x = 0xB1ACC.conjugate()
+-x = 0b1011.conjugate()
+-x = 0o777.real
+-x = (0.000000006).hex()
+-x = -100.0000j
++x = .1.is_integer()
++x = 1..imag
++x = 1E+1.imag
++x = 1E-1.real
++x = 123456789.123456789.hex()
++x = 123456789.123456789E123456789.real
++x = 123456789E123456789.conjugate()
++x = 123456789J.real
++x = 123456789.123456789J.__add__(0b1011.bit_length())
++x = 0XB1ACC.conjugate()
++x = 0B1011.conjugate()
++x = 0O777.real
++x = 0.000000006.hex()
++x = -100.0000J
+ 
+-if (10).real:
++if 10.real:
+     ...
+ 
+ y = 100[no]
+-y = 100(no)
+\ No newline at end of file
++y = 100((no))
+\ No newline at end of file
+
+```
+
+## Ruff Output
+
+```py
+x = 123456789.bit_count()
+x = (123456).__abs__()
+x = .1.is_integer()
+x = 1..imag
+x = 1E+1.imag
+x = 1E-1.real
+x = 123456789.123456789.hex()
+x = 123456789.123456789E123456789.real
+x = 123456789E123456789.conjugate()
+x = 123456789J.real
+x = 123456789.123456789J.__add__(0b1011.bit_length())
+x = 0XB1ACC.conjugate()
+x = 0B1011.conjugate()
+x = 0O777.real
+x = 0.000000006.hex()
+x = -100.0000J
+
+if 10.real:
+    ...
+
+y = 100[no]
+y = 100((no))
+```
+
+## Black Output
+
+```py
+x = (123456789).bit_count()
+x = (123456).__abs__()
+x = (0.1).is_integer()
+x = (1.0).imag
+x = (1e1).imag
+x = (1e-1).real
+x = (123456789.123456789).hex()
+x = (123456789.123456789e123456789).real
+x = (123456789e123456789).conjugate()
+x = 123456789j.real
+x = 123456789.123456789j.__add__(0b1011.bit_length())
+x = 0xB1ACC.conjugate()
+x = 0b1011.conjugate()
+x = 0o777.real
+x = (0.000000006).hex()
+x = -100.0000j
+
+if (10).real:
+    ...
+
+y = 100[no]
+y = 100(no)
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__bracketmatch_py.snap

@@ -0,0 +1,53 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/bracketmatch.py
+---
+## Input
+
+```py
+for ((x in {}) or {})['a'] in x:
+    pass
+pem_spam = lambda l, spam = {
+    "x": 3
+}: not spam.get(l.strip())
+lambda x=lambda y={1: 3}: y['x':lambda y: {1: 2}]: x
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,4 +1,4 @@
+-for ((x in {}) or {})["a"] in x:
++for ((x in {}) or {})['a'] in x:
+     pass
+ pem_spam = lambda l, spam={"x": 3}: not spam.get(l.strip())
+-lambda x=lambda y={1: 3}: y["x" : lambda y: {1: 2}]: x
+\ No newline at end of file
++lambda x=lambda y={1: 3}: y['x' : lambda y: {1: 2}]: x
+\ No newline at end of file
+
+```
+
+## Ruff Output
+
+```py
+for ((x in {}) or {})['a'] in x:
+    pass
+pem_spam = lambda l, spam={"x": 3}: not spam.get(l.strip())
+lambda x=lambda y={1: 3}: y['x' : lambda y: {1: 2}]: x
+```
+
+## Black Output
+
+```py
+for ((x in {}) or {})["a"] in x:
+    pass
+pem_spam = lambda l, spam={"x": 3}: not spam.get(l.strip())
+lambda x=lambda y={1: 3}: y["x" : lambda y: {1: 2}]: x
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__class_blank_parentheses_py.snap

@@ -0,0 +1,121 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/class_blank_parentheses.py
+---
+## Input
+
+```py
+class SimpleClassWithBlankParentheses():
+    pass
+class ClassWithSpaceParentheses ( ):
+    first_test_data = 90
+    second_test_data = 100
+    def test_func(self):
+        return None
+class ClassWithEmptyFunc(object):
+
+    def func_with_blank_parentheses():
+        return 5
+
+
+def public_func_with_blank_parentheses():
+    return None
+def class_under_the_func_with_blank_parentheses():
+    class InsideFunc():
+        pass
+class NormalClass (
+):
+    def func_for_testing(self, first, second):
+        sum = first + second
+        return sum
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -27,4 +27,4 @@
+ class NormalClass:
+     def func_for_testing(self, first, second):
+         sum = first + second
+-        return sum
+\ No newline at end of file
++        return sum
+
+```
+
+## Ruff Output
+
+```py
+class SimpleClassWithBlankParentheses:
+    pass
+
+
+class ClassWithSpaceParentheses:
+    first_test_data = 90
+    second_test_data = 100
+
+    def test_func(self):
+        return None
+
+
+class ClassWithEmptyFunc(object):
+    def func_with_blank_parentheses():
+        return 5
+
+
+def public_func_with_blank_parentheses():
+    return None
+
+
+def class_under_the_func_with_blank_parentheses():
+    class InsideFunc:
+        pass
+
+
+class NormalClass:
+    def func_for_testing(self, first, second):
+        sum = first + second
+        return sum
+
+```
+
+## Black Output
+
+```py
+class SimpleClassWithBlankParentheses:
+    pass
+
+
+class ClassWithSpaceParentheses:
+    first_test_data = 90
+    second_test_data = 100
+
+    def test_func(self):
+        return None
+
+
+class ClassWithEmptyFunc(object):
+    def func_with_blank_parentheses():
+        return 5
+
+
+def public_func_with_blank_parentheses():
+    return None
+
+
+def class_under_the_func_with_blank_parentheses():
+    class InsideFunc:
+        pass
+
+
+class NormalClass:
+    def func_for_testing(self, first, second):
+        sum = first + second
+        return sum
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__class_methods_new_line_py.snap

@@ -0,0 +1,468 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/class_methods_new_line.py
+---
+## Input
+
+```py
+class ClassSimplest:
+    pass
+class ClassWithSingleField:
+    a = 1
+class ClassWithJustTheDocstring:
+    """Just a docstring."""
+class ClassWithInit:
+    def __init__(self):
+        pass
+class ClassWithTheDocstringAndInit:
+    """Just a docstring."""
+    def __init__(self):
+        pass
+class ClassWithInitAndVars:
+    cls_var = 100
+    def __init__(self):
+        pass
+class ClassWithInitAndVarsAndDocstring:
+    """Test class"""
+    cls_var = 100
+    def __init__(self):
+        pass
+class ClassWithDecoInit:
+    @deco
+    def __init__(self):
+        pass
+class ClassWithDecoInitAndVars:
+    cls_var = 100
+    @deco
+    def __init__(self):
+        pass
+class ClassWithDecoInitAndVarsAndDocstring:
+    """Test class"""
+    cls_var = 100
+    @deco
+    def __init__(self):
+        pass
+class ClassSimplestWithInner:
+    class Inner:
+        pass
+class ClassSimplestWithInnerWithDocstring:
+    class Inner:
+        """Just a docstring."""
+        def __init__(self):
+            pass
+class ClassWithSingleFieldWithInner:
+    a = 1
+    class Inner:
+        pass
+class ClassWithJustTheDocstringWithInner:
+    """Just a docstring."""
+    class Inner:
+        pass
+class ClassWithInitWithInner:
+    class Inner:
+        pass
+    def __init__(self):
+        pass
+class ClassWithInitAndVarsWithInner:
+    cls_var = 100
+    class Inner:
+        pass
+    def __init__(self):
+        pass
+class ClassWithInitAndVarsAndDocstringWithInner:
+    """Test class"""
+    cls_var = 100
+    class Inner:
+        pass
+    def __init__(self):
+        pass
+class ClassWithDecoInitWithInner:
+    class Inner:
+        pass
+    @deco
+    def __init__(self):
+        pass
+class ClassWithDecoInitAndVarsWithInner:
+    cls_var = 100
+    class Inner:
+        pass
+    @deco
+    def __init__(self):
+        pass
+class ClassWithDecoInitAndVarsAndDocstringWithInner:
+    """Test class"""
+    cls_var = 100
+    class Inner:
+        pass
+    @deco
+    def __init__(self):
+        pass
+class ClassWithDecoInitAndVarsAndDocstringWithInner2:
+    """Test class"""
+    class Inner:
+        pass
+    cls_var = 100
+    @deco
+    def __init__(self):
+        pass
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -162,4 +162,4 @@
+ 
+     @deco
+     def __init__(self):
+-        pass
+\ No newline at end of file
++        pass
+
+```
+
+## Ruff Output
+
+```py
+class ClassSimplest:
+    pass
+
+
+class ClassWithSingleField:
+    a = 1
+
+
+class ClassWithJustTheDocstring:
+    """Just a docstring."""
+
+
+class ClassWithInit:
+    def __init__(self):
+        pass
+
+
+class ClassWithTheDocstringAndInit:
+    """Just a docstring."""
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVars:
+    cls_var = 100
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVarsAndDocstring:
+    """Test class"""
+
+    cls_var = 100
+
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInit:
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVars:
+    cls_var = 100
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsAndDocstring:
+    """Test class"""
+
+    cls_var = 100
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassSimplestWithInner:
+    class Inner:
+        pass
+
+
+class ClassSimplestWithInnerWithDocstring:
+    class Inner:
+        """Just a docstring."""
+
+        def __init__(self):
+            pass
+
+
+class ClassWithSingleFieldWithInner:
+    a = 1
+
+    class Inner:
+        pass
+
+
+class ClassWithJustTheDocstringWithInner:
+    """Just a docstring."""
+
+    class Inner:
+        pass
+
+
+class ClassWithInitWithInner:
+    class Inner:
+        pass
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVarsWithInner:
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVarsAndDocstringWithInner:
+    """Test class"""
+
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitWithInner:
+    class Inner:
+        pass
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsWithInner:
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsAndDocstringWithInner:
+    """Test class"""
+
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsAndDocstringWithInner2:
+    """Test class"""
+
+    class Inner:
+        pass
+
+    cls_var = 100
+
+    @deco
+    def __init__(self):
+        pass
+
+```
+
+## Black Output
+
+```py
+class ClassSimplest:
+    pass
+
+
+class ClassWithSingleField:
+    a = 1
+
+
+class ClassWithJustTheDocstring:
+    """Just a docstring."""
+
+
+class ClassWithInit:
+    def __init__(self):
+        pass
+
+
+class ClassWithTheDocstringAndInit:
+    """Just a docstring."""
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVars:
+    cls_var = 100
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVarsAndDocstring:
+    """Test class"""
+
+    cls_var = 100
+
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInit:
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVars:
+    cls_var = 100
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsAndDocstring:
+    """Test class"""
+
+    cls_var = 100
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassSimplestWithInner:
+    class Inner:
+        pass
+
+
+class ClassSimplestWithInnerWithDocstring:
+    class Inner:
+        """Just a docstring."""
+
+        def __init__(self):
+            pass
+
+
+class ClassWithSingleFieldWithInner:
+    a = 1
+
+    class Inner:
+        pass
+
+
+class ClassWithJustTheDocstringWithInner:
+    """Just a docstring."""
+
+    class Inner:
+        pass
+
+
+class ClassWithInitWithInner:
+    class Inner:
+        pass
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVarsWithInner:
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    def __init__(self):
+        pass
+
+
+class ClassWithInitAndVarsAndDocstringWithInner:
+    """Test class"""
+
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitWithInner:
+    class Inner:
+        pass
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsWithInner:
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsAndDocstringWithInner:
+    """Test class"""
+
+    cls_var = 100
+
+    class Inner:
+        pass
+
+    @deco
+    def __init__(self):
+        pass
+
+
+class ClassWithDecoInitAndVarsAndDocstringWithInner2:
+    """Test class"""
+
+    class Inner:
+        pass
+
+    cls_var = 100
+
+    @deco
+    def __init__(self):
+        pass
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__collections_py.snap

@@ -0,0 +1,329 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/collections.py
+---
+## Input
+
+```py
+import core, time, a
+
+from . import A, B, C
+
+# keeps existing trailing comma
+from foo import (
+    bar,
+)
+
+# also keeps existing structure
+from foo import (
+    baz,
+    qux,
+)
+
+# `as` works as well
+from foo import (
+    xyzzy as magic,
+)
+
+a = {1,2,3,}
+b = {
+1,2,
+     3}
+c = {
+    1,
+    2,
+    3,
+}
+x = 1,
+y = narf(),
+nested = {(1,2,3),(4,5,6),}
+nested_no_trailing_comma = {(1,2,3),(4,5,6)}
+nested_long_lines = ["aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb", "cccccccccccccccccccccccccccccccccccccccc", (1, 2, 3), "dddddddddddddddddddddddddddddddddddddddd"]
+{"oneple": (1,),}
+{"oneple": (1,)}
+['ls', 'lsoneple/%s' % (foo,)]
+x = {"oneple": (1,)}
+y = {"oneple": (1,),}
+assert False, ("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa wraps %s" % bar)
+
+# looping over a 1-tuple should also not get wrapped
+for x in (1,):
+    pass
+for (x,) in (1,), (2,), (3,):
+    pass
+
+[1, 2, 3,]
+
+division_result_tuple = (6/2,)
+print("foo %r", (foo.bar,))
+
+if True:
+    IGNORED_TYPES_FOR_ATTRIBUTE_CHECKING = (
+        Config.IGNORED_TYPES_FOR_ATTRIBUTE_CHECKING
+        | {pylons.controllers.WSGIController}
+    )
+
+if True:
+    ec2client.get_waiter('instance_stopped').wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={
+            'Delay': 5,
+        })
+    ec2client.get_waiter("instance_stopped").wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={"Delay": 5,},
+    )
+    ec2client.get_waiter("instance_stopped").wait(
+        InstanceIds=[instance.id], WaiterConfig={"Delay": 5,},
+    )
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -47,7 +47,7 @@
+     "oneple": (1,),
+ }
+ {"oneple": (1,)}
+-["ls", "lsoneple/%s" % (foo,)]
++['ls', 'lsoneple/%s' % (foo,)]
+ x = {"oneple": (1,)}
+ y = {
+     "oneple": (1,),
+@@ -79,10 +79,10 @@
+     )
+ 
+ if True:
+-    ec2client.get_waiter("instance_stopped").wait(
++    ec2client.get_waiter('instance_stopped').wait(
+         InstanceIds=[instance.id],
+         WaiterConfig={
+-            "Delay": 5,
++            'Delay': 5,
+         },
+     )
+     ec2client.get_waiter("instance_stopped").wait(
+@@ -96,4 +96,4 @@
+         WaiterConfig={
+             "Delay": 5,
+         },
+-    )
+\ No newline at end of file
++    )
+
+```
+
+## Ruff Output
+
+```py
+import core, time, a
+
+from . import A, B, C
+
+# keeps existing trailing comma
+from foo import (
+    bar,
+)
+
+# also keeps existing structure
+from foo import (
+    baz,
+    qux,
+)
+
+# `as` works as well
+from foo import (
+    xyzzy as magic,
+)
+
+a = {
+    1,
+    2,
+    3,
+}
+b = {1, 2, 3}
+c = {
+    1,
+    2,
+    3,
+}
+x = (1,)
+y = (narf(),)
+nested = {
+    (1, 2, 3),
+    (4, 5, 6),
+}
+nested_no_trailing_comma = {(1, 2, 3), (4, 5, 6)}
+nested_long_lines = [
+    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+    "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb",
+    "cccccccccccccccccccccccccccccccccccccccc",
+    (1, 2, 3),
+    "dddddddddddddddddddddddddddddddddddddddd",
+]
+{
+    "oneple": (1,),
+}
+{"oneple": (1,)}
+['ls', 'lsoneple/%s' % (foo,)]
+x = {"oneple": (1,)}
+y = {
+    "oneple": (1,),
+}
+assert False, (
+    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa wraps %s"
+    % bar
+)
+
+# looping over a 1-tuple should also not get wrapped
+for x in (1,):
+    pass
+for (x,) in (1,), (2,), (3,):
+    pass
+
+[
+    1,
+    2,
+    3,
+]
+
+division_result_tuple = (6 / 2,)
+print("foo %r", (foo.bar,))
+
+if True:
+    IGNORED_TYPES_FOR_ATTRIBUTE_CHECKING = (
+        Config.IGNORED_TYPES_FOR_ATTRIBUTE_CHECKING
+        | {pylons.controllers.WSGIController}
+    )
+
+if True:
+    ec2client.get_waiter('instance_stopped').wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={
+            'Delay': 5,
+        },
+    )
+    ec2client.get_waiter("instance_stopped").wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={
+            "Delay": 5,
+        },
+    )
+    ec2client.get_waiter("instance_stopped").wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={
+            "Delay": 5,
+        },
+    )
+
+```
+
+## Black Output
+
+```py
+import core, time, a
+
+from . import A, B, C
+
+# keeps existing trailing comma
+from foo import (
+    bar,
+)
+
+# also keeps existing structure
+from foo import (
+    baz,
+    qux,
+)
+
+# `as` works as well
+from foo import (
+    xyzzy as magic,
+)
+
+a = {
+    1,
+    2,
+    3,
+}
+b = {1, 2, 3}
+c = {
+    1,
+    2,
+    3,
+}
+x = (1,)
+y = (narf(),)
+nested = {
+    (1, 2, 3),
+    (4, 5, 6),
+}
+nested_no_trailing_comma = {(1, 2, 3), (4, 5, 6)}
+nested_long_lines = [
+    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
+    "bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb",
+    "cccccccccccccccccccccccccccccccccccccccc",
+    (1, 2, 3),
+    "dddddddddddddddddddddddddddddddddddddddd",
+]
+{
+    "oneple": (1,),
+}
+{"oneple": (1,)}
+["ls", "lsoneple/%s" % (foo,)]
+x = {"oneple": (1,)}
+y = {
+    "oneple": (1,),
+}
+assert False, (
+    "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa wraps %s"
+    % bar
+)
+
+# looping over a 1-tuple should also not get wrapped
+for x in (1,):
+    pass
+for (x,) in (1,), (2,), (3,):
+    pass
+
+[
+    1,
+    2,
+    3,
+]
+
+division_result_tuple = (6 / 2,)
+print("foo %r", (foo.bar,))
+
+if True:
+    IGNORED_TYPES_FOR_ATTRIBUTE_CHECKING = (
+        Config.IGNORED_TYPES_FOR_ATTRIBUTE_CHECKING
+        | {pylons.controllers.WSGIController}
+    )
+
+if True:
+    ec2client.get_waiter("instance_stopped").wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={
+            "Delay": 5,
+        },
+    )
+    ec2client.get_waiter("instance_stopped").wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={
+            "Delay": 5,
+        },
+    )
+    ec2client.get_waiter("instance_stopped").wait(
+        InstanceIds=[instance.id],
+        WaiterConfig={
+            "Delay": 5,
+        },
+    )
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__comment_after_escaped_newline_py.snap

@@ -0,0 +1,67 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comment_after_escaped_newline.py
+---
+## Input
+
+```py
+def bob(): \
+         # pylint: disable=W9016
+    pass
+
+
+def bobtwo(): \
+    \
+  # some comment here
+    pass
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,6 +1,8 @@
+-def bob():  # pylint: disable=W9016
++def bob():
++    # pylint: disable=W9016
+     pass
+ 
+ 
+-def bobtwo():  # some comment here
+-    pass
+\ No newline at end of file
++def bobtwo():
++    # some comment here
++    pass
+
+```
+
+## Ruff Output
+
+```py
+def bob():
+    # pylint: disable=W9016
+    pass
+
+
+def bobtwo():
+    # some comment here
+    pass
+
+```
+
+## Black Output
+
+```py
+def bob():  # pylint: disable=W9016
+    pass
+
+
+def bobtwo():  # some comment here
+    pass
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__comments2_py.snap

@@ -0,0 +1,734 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments2.py
+---
+## Input
+
+```py
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent  # NOT DRY
+)
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent as component  # DRY
+)
+
+# Please keep __all__ alphabetized within each category.
+
+__all__ = [
+    # Super-special typing primitives.
+    'Any',
+    'Callable',
+    'ClassVar',
+
+    # ABCs (from collections.abc).
+    'AbstractSet',  # collections.abc.Set.
+    'ByteString',
+    'Container',
+
+    # Concrete collection types.
+    'Counter',
+    'Deque',
+    'Dict',
+    'DefaultDict',
+    'List',
+    'Set',
+    'FrozenSet',
+    'NamedTuple',  # Not really a type.
+    'Generator',
+]
+
+not_shareables = [
+    # singletons
+    True,
+    False,
+    NotImplemented, ...,
+    # builtin types and objects
+    type,
+    object,
+    object(),
+    Exception(),
+    42,
+    100.0,
+    "spam",
+    # user-defined types and objects
+    Cheese,
+    Cheese("Wensleydale"),
+    SubBytes(b"spam"),
+]
+
+if 'PYTHON' in os.environ:
+    add_compiler(compiler_from_env())
+else:
+    # for compiler in compilers.values():
+         # add_compiler(compiler)
+    add_compiler(compilers[(7.0, 32)])
+    # add_compiler(compilers[(7.1, 64)])
+
+# Comment before function.
+def inline_comments_in_brackets_ruin_everything():
+    if typedargslist:
+        parameters.children = [
+            children[0],  # (1
+            body,
+            children[-1]  # )1
+        ]
+        parameters.children = [
+            children[0],
+            body,
+            children[-1],  # type: ignore
+        ]
+    else:
+        parameters.children = [
+            parameters.children[0],  # (2 what if this was actually long
+            body,
+            parameters.children[-1],  # )2
+        ]
+        parameters.children = [parameters.what_if_this_was_actually_long.children[0], body, parameters.children[-1]]  # type: ignore
+    if (self._proc is not None
+            # has the child process finished?
+            and self._returncode is None
+            # the child process has finished, but the
+            # transport hasn't been notified yet?
+            and self._proc.poll() is None):
+        pass
+    # no newline before or after
+    short = [
+     # one
+     1,
+     # two
+     2]
+
+    # no newline after
+    call(arg1, arg2, """
+short
+""", arg3=True)
+
+    ############################################################################
+
+    call2(
+    #short
+    arg1,
+    #but
+    arg2,
+    #multiline
+    """
+short
+""",
+    # yup
+    arg3=True)
+    lcomp = [
+        element  # yup
+        for element in collection  # yup
+        if element is not None  # right
+    ]
+    lcomp2 = [
+        # hello
+        element
+        # yup
+        for element in collection
+        # right
+        if element is not None
+    ]
+    lcomp3 = [
+        # This one is actually too long to fit in a single line.
+        element.split('\n', 1)[0]
+        # yup
+        for element in collection.select_elements()
+        # right
+        if element is not None
+    ]
+    while True:
+        if False:
+            continue
+
+            # and round and round we go
+        # and round and round we go
+
+   # let's return
+    return Node(
+        syms.simple_stmt,
+        [
+            Node(statement, result),
+            Leaf(token.NEWLINE, '\n')  # FIXME: \r\n?
+        ],
+    )
+
+CONFIG_FILES = [CONFIG_FILE, ] + SHARED_CONFIG_FILES + USER_CONFIG_FILES  # type: Final
+
+class Test:
+    def _init_host(self, parsed) -> None:
+        if (parsed.hostname is None or  # type: ignore
+                not parsed.hostname.strip()):
+            pass
+
+#######################
+### SECTION COMMENT ###
+#######################
+
+
+instruction()#comment with bad spacing
+
+# END COMMENTS
+# MORE END COMMENTS
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,31 +1,31 @@
+ from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+-    MyLovelyCompanyTeamProjectComponent,  # NOT DRY
++    MyLovelyCompanyTeamProjectComponent,
+ )
+ from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+-    MyLovelyCompanyTeamProjectComponent as component,  # DRY
++    MyLovelyCompanyTeamProjectComponent as component,
+ )
+ 
+ # Please keep __all__ alphabetized within each category.
+ 
+ __all__ = [
+     # Super-special typing primitives.
+-    "Any",
+-    "Callable",
+-    "ClassVar",
++    'Any',
++    'Callable',
++    'ClassVar',
+     # ABCs (from collections.abc).
+-    "AbstractSet",  # collections.abc.Set.
+-    "ByteString",
+-    "Container",
++    'AbstractSet',
++    'ByteString',
++    'Container',
+     # Concrete collection types.
+-    "Counter",
+-    "Deque",
+-    "Dict",
+-    "DefaultDict",
+-    "List",
+-    "Set",
+-    "FrozenSet",
+-    "NamedTuple",  # Not really a type.
+-    "Generator",
++    'Counter',
++    'Deque',
++    'Dict',
++    'DefaultDict',
++    'List',
++    'Set',
++    'FrozenSet',
++    'NamedTuple',
++    'Generator',
+ ]
+ 
+ not_shareables = [
+@@ -48,38 +48,45 @@
+     SubBytes(b"spam"),
+ ]
+ 
+-if "PYTHON" in os.environ:
++if 'PYTHON' in os.environ:
+     add_compiler(compiler_from_env())
+ else:
+     # for compiler in compilers.values():
+     # add_compiler(compiler)
+     add_compiler(compilers[(7.0, 32)])
+-    # add_compiler(compilers[(7.1, 64)])
+ 
+ 
++# add_compiler(compilers[(7.1, 64)])
++
+ # Comment before function.
+ def inline_comments_in_brackets_ruin_everything():
+     if typedargslist:
+-        parameters.children = [children[0], body, children[-1]]  # (1  # )1
++        parameters.children = [children[0], body, children[-1]]
+         parameters.children = [
+             children[0],
+             body,
+-            children[-1],  # type: ignore
++            children[-1],
+         ]
+     else:
+         parameters.children = [
+-            parameters.children[0],  # (2 what if this was actually long
++            parameters.children[0],
+             body,
+-            parameters.children[-1],  # )2
++            parameters.children[-1],
+         ]
+-        parameters.children = [parameters.what_if_this_was_actually_long.children[0], body, parameters.children[-1]]  # type: ignore
++        parameters.children = [
++            parameters.what_if_this_was_actually_long.children[0],
++            body,
++            parameters.children[-1],
++        ]
+     if (
+         self._proc is not None
+-        # has the child process finished?
+-        and self._returncode is None
+-        # the child process has finished, but the
++        and # has the child process finished?
++        self._returncode
++        is None
++        and # the child process has finished, but the
+         # transport hasn't been notified yet?
+-        and self._proc.poll() is None
++        self._proc.poll()
++        is None
+     ):
+         pass
+     # no newline before or after
+@@ -103,47 +110,47 @@
+     ############################################################################
+ 
+     call2(
+-        # short
++        #short
+         arg1,
+-        # but
++        #but
+         arg2,
+-        # multiline
++        #multiline
+         """
+ short
+ """,
+-        # yup
+-        arg3=True,
++        arg3=# yup
++        True,
+     )
+-    lcomp = [
+-        element for element in collection if element is not None  # yup  # yup  # right
+-    ]
++    lcomp = [element for element in collection if element is not None]  # yup  # yup  # right
+     lcomp2 = [
+         # hello
+         element
+-        # yup
+-        for element in collection
+-        # right
+-        if element is not None
++        for # yup
++        element in collection
++        if # right
++        element
++        is not None
+     ]
+     lcomp3 = [
+         # This one is actually too long to fit in a single line.
+-        element.split("\n", 1)[0]
+-        # yup
+-        for element in collection.select_elements()
+-        # right
+-        if element is not None
++        element.split('\n', 1)[0]
++        for # yup
++        element in collection.select_elements()
++        if # right
++        element
++        is not None
+     ]
+     while True:
+         if False:
+             continue
+ 
+-            # and round and round we go
+-        # and round and round we go
++    # and round and round we go
++    # and round and round we go
+ 
+     # let's return
+     return Node(
+         syms.simple_stmt,
+-        [Node(statement, result), Leaf(token.NEWLINE, "\n")],  # FIXME: \r\n?
++        [Node(statement, result), Leaf(token.NEWLINE, '\n')],  # FIXME: \r\n?
+     )
+ 
+ 
+@@ -167,7 +174,7 @@
+ #######################
+ 
+ 
+-instruction()  # comment with bad spacing
++instruction()  #comment with bad spacing
+ 
+ # END COMMENTS
+-# MORE END COMMENTS
+\ No newline at end of file
++# MORE END COMMENTS
+
+```
+
+## Ruff Output
+
+```py
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent,
+)
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent as component,
+)
+
+# Please keep __all__ alphabetized within each category.
+
+__all__ = [
+    # Super-special typing primitives.
+    'Any',
+    'Callable',
+    'ClassVar',
+    # ABCs (from collections.abc).
+    'AbstractSet',
+    'ByteString',
+    'Container',
+    # Concrete collection types.
+    'Counter',
+    'Deque',
+    'Dict',
+    'DefaultDict',
+    'List',
+    'Set',
+    'FrozenSet',
+    'NamedTuple',
+    'Generator',
+]
+
+not_shareables = [
+    # singletons
+    True,
+    False,
+    NotImplemented,
+    ...,
+    # builtin types and objects
+    type,
+    object,
+    object(),
+    Exception(),
+    42,
+    100.0,
+    "spam",
+    # user-defined types and objects
+    Cheese,
+    Cheese("Wensleydale"),
+    SubBytes(b"spam"),
+]
+
+if 'PYTHON' in os.environ:
+    add_compiler(compiler_from_env())
+else:
+    # for compiler in compilers.values():
+    # add_compiler(compiler)
+    add_compiler(compilers[(7.0, 32)])
+
+
+# add_compiler(compilers[(7.1, 64)])
+
+# Comment before function.
+def inline_comments_in_brackets_ruin_everything():
+    if typedargslist:
+        parameters.children = [children[0], body, children[-1]]
+        parameters.children = [
+            children[0],
+            body,
+            children[-1],
+        ]
+    else:
+        parameters.children = [
+            parameters.children[0],
+            body,
+            parameters.children[-1],
+        ]
+        parameters.children = [
+            parameters.what_if_this_was_actually_long.children[0],
+            body,
+            parameters.children[-1],
+        ]
+    if (
+        self._proc is not None
+        and # has the child process finished?
+        self._returncode
+        is None
+        and # the child process has finished, but the
+        # transport hasn't been notified yet?
+        self._proc.poll()
+        is None
+    ):
+        pass
+    # no newline before or after
+    short = [
+        # one
+        1,
+        # two
+        2,
+    ]
+
+    # no newline after
+    call(
+        arg1,
+        arg2,
+        """
+short
+""",
+        arg3=True,
+    )
+
+    ############################################################################
+
+    call2(
+        #short
+        arg1,
+        #but
+        arg2,
+        #multiline
+        """
+short
+""",
+        arg3=# yup
+        True,
+    )
+    lcomp = [element for element in collection if element is not None]  # yup  # yup  # right
+    lcomp2 = [
+        # hello
+        element
+        for # yup
+        element in collection
+        if # right
+        element
+        is not None
+    ]
+    lcomp3 = [
+        # This one is actually too long to fit in a single line.
+        element.split('\n', 1)[0]
+        for # yup
+        element in collection.select_elements()
+        if # right
+        element
+        is not None
+    ]
+    while True:
+        if False:
+            continue
+
+    # and round and round we go
+    # and round and round we go
+
+    # let's return
+    return Node(
+        syms.simple_stmt,
+        [Node(statement, result), Leaf(token.NEWLINE, '\n')],  # FIXME: \r\n?
+    )
+
+
+CONFIG_FILES = (
+    [
+        CONFIG_FILE,
+    ]
+    + SHARED_CONFIG_FILES
+    + USER_CONFIG_FILES
+)  # type: Final
+
+
+class Test:
+    def _init_host(self, parsed) -> None:
+        if parsed.hostname is None or not parsed.hostname.strip():  # type: ignore
+            pass
+
+
+#######################
+### SECTION COMMENT ###
+#######################
+
+
+instruction()  #comment with bad spacing
+
+# END COMMENTS
+# MORE END COMMENTS
+
+```
+
+## Black Output
+
+```py
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent,  # NOT DRY
+)
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent as component,  # DRY
+)
+
+# Please keep __all__ alphabetized within each category.
+
+__all__ = [
+    # Super-special typing primitives.
+    "Any",
+    "Callable",
+    "ClassVar",
+    # ABCs (from collections.abc).
+    "AbstractSet",  # collections.abc.Set.
+    "ByteString",
+    "Container",
+    # Concrete collection types.
+    "Counter",
+    "Deque",
+    "Dict",
+    "DefaultDict",
+    "List",
+    "Set",
+    "FrozenSet",
+    "NamedTuple",  # Not really a type.
+    "Generator",
+]
+
+not_shareables = [
+    # singletons
+    True,
+    False,
+    NotImplemented,
+    ...,
+    # builtin types and objects
+    type,
+    object,
+    object(),
+    Exception(),
+    42,
+    100.0,
+    "spam",
+    # user-defined types and objects
+    Cheese,
+    Cheese("Wensleydale"),
+    SubBytes(b"spam"),
+]
+
+if "PYTHON" in os.environ:
+    add_compiler(compiler_from_env())
+else:
+    # for compiler in compilers.values():
+    # add_compiler(compiler)
+    add_compiler(compilers[(7.0, 32)])
+    # add_compiler(compilers[(7.1, 64)])
+
+
+# Comment before function.
+def inline_comments_in_brackets_ruin_everything():
+    if typedargslist:
+        parameters.children = [children[0], body, children[-1]]  # (1  # )1
+        parameters.children = [
+            children[0],
+            body,
+            children[-1],  # type: ignore
+        ]
+    else:
+        parameters.children = [
+            parameters.children[0],  # (2 what if this was actually long
+            body,
+            parameters.children[-1],  # )2
+        ]
+        parameters.children = [parameters.what_if_this_was_actually_long.children[0], body, parameters.children[-1]]  # type: ignore
+    if (
+        self._proc is not None
+        # has the child process finished?
+        and self._returncode is None
+        # the child process has finished, but the
+        # transport hasn't been notified yet?
+        and self._proc.poll() is None
+    ):
+        pass
+    # no newline before or after
+    short = [
+        # one
+        1,
+        # two
+        2,
+    ]
+
+    # no newline after
+    call(
+        arg1,
+        arg2,
+        """
+short
+""",
+        arg3=True,
+    )
+
+    ############################################################################
+
+    call2(
+        # short
+        arg1,
+        # but
+        arg2,
+        # multiline
+        """
+short
+""",
+        # yup
+        arg3=True,
+    )
+    lcomp = [
+        element for element in collection if element is not None  # yup  # yup  # right
+    ]
+    lcomp2 = [
+        # hello
+        element
+        # yup
+        for element in collection
+        # right
+        if element is not None
+    ]
+    lcomp3 = [
+        # This one is actually too long to fit in a single line.
+        element.split("\n", 1)[0]
+        # yup
+        for element in collection.select_elements()
+        # right
+        if element is not None
+    ]
+    while True:
+        if False:
+            continue
+
+            # and round and round we go
+        # and round and round we go
+
+    # let's return
+    return Node(
+        syms.simple_stmt,
+        [Node(statement, result), Leaf(token.NEWLINE, "\n")],  # FIXME: \r\n?
+    )
+
+
+CONFIG_FILES = (
+    [
+        CONFIG_FILE,
+    ]
+    + SHARED_CONFIG_FILES
+    + USER_CONFIG_FILES
+)  # type: Final
+
+
+class Test:
+    def _init_host(self, parsed) -> None:
+        if parsed.hostname is None or not parsed.hostname.strip():  # type: ignore
+            pass
+
+
+#######################
+### SECTION COMMENT ###
+#######################
+
+
+instruction()  # comment with bad spacing
+
+# END COMMENTS
+# MORE END COMMENTS
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__comments4_py.snap

@@ -0,0 +1,450 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments4.py
+---
+## Input
+
+```py
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent,  # NOT DRY
+)
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent as component,  # DRY
+)
+
+
+class C:
+    @pytest.mark.parametrize(
+        ("post_data", "message"),
+        [
+            # metadata_version errors.
+            (
+                {},
+                "None is an invalid value for Metadata-Version. Error: This field is"
+                " required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {"metadata_version": "-1"},
+                "'-1' is an invalid value for Metadata-Version. Error: Unknown Metadata"
+                " Version see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            # name errors.
+            (
+                {"metadata_version": "1.2"},
+                "'' is an invalid value for Name. Error: This field is required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {"metadata_version": "1.2", "name": "foo-"},
+                "'foo-' is an invalid value for Name. Error: Must start and end with a"
+                " letter or numeral and contain only ascii numeric and '.', '_' and"
+                " '-'. see https://packaging.python.org/specifications/core-metadata",
+            ),
+            # version errors.
+            (
+                {"metadata_version": "1.2", "name": "example"},
+                "'' is an invalid value for Version. Error: This field is required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {"metadata_version": "1.2", "name": "example", "version": "dog"},
+                "'dog' is an invalid value for Version. Error: Must start and end with"
+                " a letter or numeral and contain only ascii numeric and '.', '_' and"
+                " '-'. see https://packaging.python.org/specifications/core-metadata",
+            ),
+        ],
+    )
+    def test_fails_invalid_post_data(
+        self, pyramid_config, db_request, post_data, message
+    ):
+        pyramid_config.testing_securitypolicy(userid=1)
+        db_request.POST = MultiDict(post_data)
+
+
+def foo(list_a, list_b):
+    results = (
+        User.query.filter(User.foo == "bar")
+        .filter(  # Because foo.
+            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+        )
+        .filter(User.xyz.is_(None))
+        # Another comment about the filtering on is_quux goes here.
+        .filter(db.not_(User.is_pending.astext.cast(db.Boolean).is_(True)))
+        .order_by(User.created_at.desc())
+        .with_for_update(key_share=True)
+        .all()
+    )
+    return results
+
+
+def foo2(list_a, list_b):
+    # Standalone comment reasonably placed.
+    return (
+        User.query.filter(User.foo == "bar")
+        .filter(
+            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+        )
+        .filter(User.xyz.is_(None))
+    )
+
+
+def foo3(list_a, list_b):
+    return (
+        # Standlone comment but weirdly placed.
+        User.query.filter(User.foo == "bar")
+        .filter(
+            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+        )
+        .filter(User.xyz.is_(None))
+    )
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,8 +1,8 @@
+ from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+-    MyLovelyCompanyTeamProjectComponent,  # NOT DRY
++    MyLovelyCompanyTeamProjectComponent,
+ )
+ from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+-    MyLovelyCompanyTeamProjectComponent as component,  # DRY
++    MyLovelyCompanyTeamProjectComponent as component,
+ )
+ 
+ 
+@@ -10,39 +10,50 @@
+     @pytest.mark.parametrize(
+         ("post_data", "message"),
+         [
+-            # metadata_version errors.
+-            (
++            (# metadata_version errors.
+                 {},
+                 "None is an invalid value for Metadata-Version. Error: This field is"
+                 " required. see"
+                 " https://packaging.python.org/specifications/core-metadata",
+             ),
+             (
+-                {"metadata_version": "-1"},
++                {
++                    "metadata_version": "-1",
++                },
+                 "'-1' is an invalid value for Metadata-Version. Error: Unknown Metadata"
+                 " Version see"
+                 " https://packaging.python.org/specifications/core-metadata",
+             ),
+-            # name errors.
+-            (
+-                {"metadata_version": "1.2"},
++            (# name errors.
++                {
++                    "metadata_version": "1.2",
++                },
+                 "'' is an invalid value for Name. Error: This field is required. see"
+                 " https://packaging.python.org/specifications/core-metadata",
+             ),
+             (
+-                {"metadata_version": "1.2", "name": "foo-"},
++                {
++                    "metadata_version": "1.2",
++                    "name": "foo-",
++                },
+                 "'foo-' is an invalid value for Name. Error: Must start and end with a"
+                 " letter or numeral and contain only ascii numeric and '.', '_' and"
+                 " '-'. see https://packaging.python.org/specifications/core-metadata",
+             ),
+-            # version errors.
+-            (
+-                {"metadata_version": "1.2", "name": "example"},
++            (# version errors.
++                {
++                    "metadata_version": "1.2",
++                    "name": "example",
++                },
+                 "'' is an invalid value for Version. Error: This field is required. see"
+                 " https://packaging.python.org/specifications/core-metadata",
+             ),
+             (
+-                {"metadata_version": "1.2", "name": "example", "version": "dog"},
++                {
++                    "metadata_version": "1.2",
++                    "name": "example",
++                    "version": "dog",
++                },
+                 "'dog' is an invalid value for Version. Error: Must start and end with"
+                 " a letter or numeral and contain only ascii numeric and '.', '_' and"
+                 " '-'. see https://packaging.python.org/specifications/core-metadata",
+@@ -50,45 +61,34 @@
+         ],
+     )
+     def test_fails_invalid_post_data(
+-        self, pyramid_config, db_request, post_data, message
++        self,
++        pyramid_config,
++        db_request,
++        post_data,
++        message,
+     ):
+         pyramid_config.testing_securitypolicy(userid=1)
+         db_request.POST = MultiDict(post_data)
+ 
+ 
+ def foo(list_a, list_b):
+-    results = (
+-        User.query.filter(User.foo == "bar")
+-        .filter(  # Because foo.
+-            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+-        )
+-        .filter(User.xyz.is_(None))
+-        # Another comment about the filtering on is_quux goes here.
+-        .filter(db.not_(User.is_pending.astext.cast(db.Boolean).is_(True)))
+-        .order_by(User.created_at.desc())
+-        .with_for_update(key_share=True)
+-        .all()
+-    )
++    results = User.query.filter(User.foo == "bar").filter(  # Because foo.
++        db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
++    ).filter(User.xyz.is_(None)).filter(
++        db.not_(User.is_pending.astext.cast(db.Boolean).is_(True))
++    ).order_by(User.created_at.desc()).with_for_update(key_share=True).all()
+     return results
+ 
+ 
+ def foo2(list_a, list_b):
+     # Standalone comment reasonably placed.
+-    return (
+-        User.query.filter(User.foo == "bar")
+-        .filter(
+-            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+-        )
+-        .filter(User.xyz.is_(None))
+-    )
++    return User.query.filter(User.foo == "bar").filter(
++        db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
++    ).filter(User.xyz.is_(None))
+ 
+ 
+ def foo3(list_a, list_b):
+-    return (
+-        # Standlone comment but weirdly placed.
+-        User.query.filter(User.foo == "bar")
+-        .filter(
+-            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+-        )
+-        .filter(User.xyz.is_(None))
+-    )
+\ No newline at end of file
++    return # Standlone comment but weirdly placed.
++    User.query.filter(User.foo == "bar").filter(
++        db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
++    ).filter(User.xyz.is_(None))
+
+```
+
+## Ruff Output
+
+```py
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent,
+)
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent as component,
+)
+
+
+class C:
+    @pytest.mark.parametrize(
+        ("post_data", "message"),
+        [
+            (# metadata_version errors.
+                {},
+                "None is an invalid value for Metadata-Version. Error: This field is"
+                " required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {
+                    "metadata_version": "-1",
+                },
+                "'-1' is an invalid value for Metadata-Version. Error: Unknown Metadata"
+                " Version see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (# name errors.
+                {
+                    "metadata_version": "1.2",
+                },
+                "'' is an invalid value for Name. Error: This field is required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {
+                    "metadata_version": "1.2",
+                    "name": "foo-",
+                },
+                "'foo-' is an invalid value for Name. Error: Must start and end with a"
+                " letter or numeral and contain only ascii numeric and '.', '_' and"
+                " '-'. see https://packaging.python.org/specifications/core-metadata",
+            ),
+            (# version errors.
+                {
+                    "metadata_version": "1.2",
+                    "name": "example",
+                },
+                "'' is an invalid value for Version. Error: This field is required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {
+                    "metadata_version": "1.2",
+                    "name": "example",
+                    "version": "dog",
+                },
+                "'dog' is an invalid value for Version. Error: Must start and end with"
+                " a letter or numeral and contain only ascii numeric and '.', '_' and"
+                " '-'. see https://packaging.python.org/specifications/core-metadata",
+            ),
+        ],
+    )
+    def test_fails_invalid_post_data(
+        self,
+        pyramid_config,
+        db_request,
+        post_data,
+        message,
+    ):
+        pyramid_config.testing_securitypolicy(userid=1)
+        db_request.POST = MultiDict(post_data)
+
+
+def foo(list_a, list_b):
+    results = User.query.filter(User.foo == "bar").filter(  # Because foo.
+        db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+    ).filter(User.xyz.is_(None)).filter(
+        db.not_(User.is_pending.astext.cast(db.Boolean).is_(True))
+    ).order_by(User.created_at.desc()).with_for_update(key_share=True).all()
+    return results
+
+
+def foo2(list_a, list_b):
+    # Standalone comment reasonably placed.
+    return User.query.filter(User.foo == "bar").filter(
+        db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+    ).filter(User.xyz.is_(None))
+
+
+def foo3(list_a, list_b):
+    return # Standlone comment but weirdly placed.
+    User.query.filter(User.foo == "bar").filter(
+        db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+    ).filter(User.xyz.is_(None))
+
+```
+
+## Black Output
+
+```py
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent,  # NOT DRY
+)
+from com.my_lovely_company.my_lovely_team.my_lovely_project.my_lovely_component import (
+    MyLovelyCompanyTeamProjectComponent as component,  # DRY
+)
+
+
+class C:
+    @pytest.mark.parametrize(
+        ("post_data", "message"),
+        [
+            # metadata_version errors.
+            (
+                {},
+                "None is an invalid value for Metadata-Version. Error: This field is"
+                " required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {"metadata_version": "-1"},
+                "'-1' is an invalid value for Metadata-Version. Error: Unknown Metadata"
+                " Version see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            # name errors.
+            (
+                {"metadata_version": "1.2"},
+                "'' is an invalid value for Name. Error: This field is required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {"metadata_version": "1.2", "name": "foo-"},
+                "'foo-' is an invalid value for Name. Error: Must start and end with a"
+                " letter or numeral and contain only ascii numeric and '.', '_' and"
+                " '-'. see https://packaging.python.org/specifications/core-metadata",
+            ),
+            # version errors.
+            (
+                {"metadata_version": "1.2", "name": "example"},
+                "'' is an invalid value for Version. Error: This field is required. see"
+                " https://packaging.python.org/specifications/core-metadata",
+            ),
+            (
+                {"metadata_version": "1.2", "name": "example", "version": "dog"},
+                "'dog' is an invalid value for Version. Error: Must start and end with"
+                " a letter or numeral and contain only ascii numeric and '.', '_' and"
+                " '-'. see https://packaging.python.org/specifications/core-metadata",
+            ),
+        ],
+    )
+    def test_fails_invalid_post_data(
+        self, pyramid_config, db_request, post_data, message
+    ):
+        pyramid_config.testing_securitypolicy(userid=1)
+        db_request.POST = MultiDict(post_data)
+
+
+def foo(list_a, list_b):
+    results = (
+        User.query.filter(User.foo == "bar")
+        .filter(  # Because foo.
+            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+        )
+        .filter(User.xyz.is_(None))
+        # Another comment about the filtering on is_quux goes here.
+        .filter(db.not_(User.is_pending.astext.cast(db.Boolean).is_(True)))
+        .order_by(User.created_at.desc())
+        .with_for_update(key_share=True)
+        .all()
+    )
+    return results
+
+
+def foo2(list_a, list_b):
+    # Standalone comment reasonably placed.
+    return (
+        User.query.filter(User.foo == "bar")
+        .filter(
+            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+        )
+        .filter(User.xyz.is_(None))
+    )
+
+
+def foo3(list_a, list_b):
+    return (
+        # Standlone comment but weirdly placed.
+        User.query.filter(User.foo == "bar")
+        .filter(
+            db.or_(User.field_a.astext.in_(list_a), User.field_b.astext.in_(list_b))
+        )
+        .filter(User.xyz.is_(None))
+    )
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__comments6_py.snap

@@ -0,0 +1,554 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments6.py
+---
+## Input
+
+```py
+from typing import Any, Tuple
+
+
+def f(
+    a,  # type: int
+):
+    pass
+
+
+# test type comments
+def f(a, b, c, d, e, f, g, h, i):
+    # type: (int, int, int, int, int, int, int, int, int) -> None
+    pass
+
+
+def f(
+    a,  # type: int
+    b,  # type: int
+    c,  # type: int
+    d,  # type: int
+    e,  # type: int
+    f,  # type: int
+    g,  # type: int
+    h,  # type: int
+    i,  # type: int
+):
+    # type: (...) -> None
+    pass
+
+
+def f(
+    arg,  # type: int
+    *args,  # type: *Any
+    default=False,  # type: bool
+    **kwargs,  # type: **Any
+):
+    # type: (...) -> None
+    pass
+
+
+def f(
+    a,  # type: int
+    b,  # type: int
+    c,  # type: int
+    d,  # type: int
+):
+    # type: (...) -> None
+
+    element = 0  # type: int
+    another_element = 1  # type: float
+    another_element_with_long_name = 2  # type: int
+    another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style = (
+        3
+    )  # type: int
+    an_element_with_a_long_value = calls() or more_calls() and more()  # type: bool
+
+    tup = (
+        another_element,
+        another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style,
+    )  # type: Tuple[int, int]
+
+    a = (
+        element
+        + another_element
+        + another_element_with_long_name
+        + element
+        + another_element
+        + another_element_with_long_name
+    )  # type: int
+
+
+def f(
+    x,  # not a type comment
+    y,  # type: int
+):
+    # type: (...) -> None
+    pass
+
+
+def f(
+    x,  # not a type comment
+):  # type: (int) -> None
+    pass
+
+
+def func(
+    a=some_list[0],  # type: int
+):  # type: () -> int
+    c = call(
+        0.0123,
+        0.0456,
+        0.0789,
+        0.0123,
+        0.0456,
+        0.0789,
+        0.0123,
+        0.0456,
+        0.0789,
+        a[-1],  # type: ignore
+    )
+
+    c = call(
+        "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa"  # type: ignore
+    )
+
+
+result = (  # aaa
+    "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+)
+
+AAAAAAAAAAAAA = [AAAAAAAAAAAAA] + SHARED_AAAAAAAAAAAAA + USER_AAAAAAAAAAAAA + AAAAAAAAAAAAA  # type: ignore
+
+call_to_some_function_asdf(
+    foo,
+    [AAAAAAAAAAAAAAAAAAAAAAA, AAAAAAAAAAAAAAAAAAAAAAA, AAAAAAAAAAAAAAAAAAAAAAA, BBBBBBBBBBBB],  # type: ignore
+)
+
+aaaaaaaaaaaaa, bbbbbbbbb = map(list, map(itertools.chain.from_iterable, zip(*items)))  # type: ignore[arg-type]
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -2,8 +2,8 @@
+ 
+ 
+ def f(
+-    a,  # type: int
+-):
++    a,
++):  # type: int
+     pass
+ 
+ 
+@@ -14,44 +14,42 @@
+ 
+ 
+ def f(
+-    a,  # type: int
+-    b,  # type: int
+-    c,  # type: int
+-    d,  # type: int
+-    e,  # type: int
+-    f,  # type: int
+-    g,  # type: int
+-    h,  # type: int
+-    i,  # type: int
+-):
++    a,
++    b,
++    c,
++    d,
++    e,
++    f,
++    g,
++    h,
++    i,
++):  # type: int# type: int# type: int# type: int# type: int# type: int# type: int# type: int# type: int
+     # type: (...) -> None
+     pass
+ 
+ 
+ def f(
+-    arg,  # type: int
+-    *args,  # type: *Any
+-    default=False,  # type: bool
+-    **kwargs,  # type: **Any
+-):
++    arg,
++    *args,
++    default=False,
++    **kwargs,
++):  # type: int# type: *Any
+     # type: (...) -> None
+     pass
+ 
+ 
+ def f(
+-    a,  # type: int
+-    b,  # type: int
+-    c,  # type: int
+-    d,  # type: int
+-):
++    a,
++    b,
++    c,
++    d,
++):  # type: int# type: int# type: int# type: int# type: int
+     # type: (...) -> None
+ 
+     element = 0  # type: int
+     another_element = 1  # type: float
+     another_element_with_long_name = 2  # type: int
+-    another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style = (
+-        3
+-    )  # type: int
++    another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style = 3  # type: int
+     an_element_with_a_long_value = calls() or more_calls() and more()  # type: bool
+ 
+     tup = (
+@@ -66,26 +64,26 @@
+         + element
+         + another_element
+         + another_element_with_long_name
+-    )  # type: int
++    )
+ 
+ 
+ def f(
+-    x,  # not a type comment
+-    y,  # type: int
+-):
++    x,
++    y,
++):  # not a type comment# type: int
+     # type: (...) -> None
+     pass
+ 
+ 
+ def f(
+-    x,  # not a type comment
+-):  # type: (int) -> None
++    x,
++):  # not a type comment# type: (int) -> None
+     pass
+ 
+ 
+ def func(
+-    a=some_list[0],  # type: int
+-):  # type: () -> int
++    a=some_list[0],
++):
+     c = call(
+         0.0123,
+         0.0456,
+@@ -96,23 +94,37 @@
+         0.0123,
+         0.0456,
+         0.0789,
+-        a[-1],  # type: ignore
++        a[-1],
+     )
+ 
+     c = call(
+-        "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa"  # type: ignore
++        "aaaaaaaa",
++        "aaaaaaaa",
++        "aaaaaaaa",
++        "aaaaaaaa",
++        "aaaaaaaa",
++        "aaaaaaaa",
++        "aaaaaaaa",
+     )
+ 
+ 
+-result = (  # aaa
+-    "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+-)
++result = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"  # aaa
+ 
+-AAAAAAAAAAAAA = [AAAAAAAAAAAAA] + SHARED_AAAAAAAAAAAAA + USER_AAAAAAAAAAAAA + AAAAAAAAAAAAA  # type: ignore
++AAAAAAAAAAAAA = (
++    [AAAAAAAAAAAAA]
++    + SHARED_AAAAAAAAAAAAA
++    + USER_AAAAAAAAAAAAA
++    + AAAAAAAAAAAAA
++)  # type: ignore
+ 
+ call_to_some_function_asdf(
+     foo,
+-    [AAAAAAAAAAAAAAAAAAAAAAA, AAAAAAAAAAAAAAAAAAAAAAA, AAAAAAAAAAAAAAAAAAAAAAA, BBBBBBBBBBBB],  # type: ignore
++    [
++        AAAAAAAAAAAAAAAAAAAAAAA,
++        AAAAAAAAAAAAAAAAAAAAAAA,
++        AAAAAAAAAAAAAAAAAAAAAAA,
++        BBBBBBBBBBBB,
++    ],
+ )
+ 
+ aaaaaaaaaaaaa, bbbbbbbbb = map(list, map(itertools.chain.from_iterable, zip(*items)))  # type: ignore[arg-type]
+\ No newline at end of file
+
+```
+
+## Ruff Output
+
+```py
+from typing import Any, Tuple
+
+
+def f(
+    a,
+):  # type: int
+    pass
+
+
+# test type comments
+def f(a, b, c, d, e, f, g, h, i):
+    # type: (int, int, int, int, int, int, int, int, int) -> None
+    pass
+
+
+def f(
+    a,
+    b,
+    c,
+    d,
+    e,
+    f,
+    g,
+    h,
+    i,
+):  # type: int# type: int# type: int# type: int# type: int# type: int# type: int# type: int# type: int
+    # type: (...) -> None
+    pass
+
+
+def f(
+    arg,
+    *args,
+    default=False,
+    **kwargs,
+):  # type: int# type: *Any
+    # type: (...) -> None
+    pass
+
+
+def f(
+    a,
+    b,
+    c,
+    d,
+):  # type: int# type: int# type: int# type: int# type: int
+    # type: (...) -> None
+
+    element = 0  # type: int
+    another_element = 1  # type: float
+    another_element_with_long_name = 2  # type: int
+    another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style = 3  # type: int
+    an_element_with_a_long_value = calls() or more_calls() and more()  # type: bool
+
+    tup = (
+        another_element,
+        another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style,
+    )  # type: Tuple[int, int]
+
+    a = (
+        element
+        + another_element
+        + another_element_with_long_name
+        + element
+        + another_element
+        + another_element_with_long_name
+    )
+
+
+def f(
+    x,
+    y,
+):  # not a type comment# type: int
+    # type: (...) -> None
+    pass
+
+
+def f(
+    x,
+):  # not a type comment# type: (int) -> None
+    pass
+
+
+def func(
+    a=some_list[0],
+):
+    c = call(
+        0.0123,
+        0.0456,
+        0.0789,
+        0.0123,
+        0.0456,
+        0.0789,
+        0.0123,
+        0.0456,
+        0.0789,
+        a[-1],
+    )
+
+    c = call(
+        "aaaaaaaa",
+        "aaaaaaaa",
+        "aaaaaaaa",
+        "aaaaaaaa",
+        "aaaaaaaa",
+        "aaaaaaaa",
+        "aaaaaaaa",
+    )
+
+
+result = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"  # aaa
+
+AAAAAAAAAAAAA = (
+    [AAAAAAAAAAAAA]
+    + SHARED_AAAAAAAAAAAAA
+    + USER_AAAAAAAAAAAAA
+    + AAAAAAAAAAAAA
+)  # type: ignore
+
+call_to_some_function_asdf(
+    foo,
+    [
+        AAAAAAAAAAAAAAAAAAAAAAA,
+        AAAAAAAAAAAAAAAAAAAAAAA,
+        AAAAAAAAAAAAAAAAAAAAAAA,
+        BBBBBBBBBBBB,
+    ],
+)
+
+aaaaaaaaaaaaa, bbbbbbbbb = map(list, map(itertools.chain.from_iterable, zip(*items)))  # type: ignore[arg-type]
+```
+
+## Black Output
+
+```py
+from typing import Any, Tuple
+
+
+def f(
+    a,  # type: int
+):
+    pass
+
+
+# test type comments
+def f(a, b, c, d, e, f, g, h, i):
+    # type: (int, int, int, int, int, int, int, int, int) -> None
+    pass
+
+
+def f(
+    a,  # type: int
+    b,  # type: int
+    c,  # type: int
+    d,  # type: int
+    e,  # type: int
+    f,  # type: int
+    g,  # type: int
+    h,  # type: int
+    i,  # type: int
+):
+    # type: (...) -> None
+    pass
+
+
+def f(
+    arg,  # type: int
+    *args,  # type: *Any
+    default=False,  # type: bool
+    **kwargs,  # type: **Any
+):
+    # type: (...) -> None
+    pass
+
+
+def f(
+    a,  # type: int
+    b,  # type: int
+    c,  # type: int
+    d,  # type: int
+):
+    # type: (...) -> None
+
+    element = 0  # type: int
+    another_element = 1  # type: float
+    another_element_with_long_name = 2  # type: int
+    another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style = (
+        3
+    )  # type: int
+    an_element_with_a_long_value = calls() or more_calls() and more()  # type: bool
+
+    tup = (
+        another_element,
+        another_really_really_long_element_with_a_unnecessarily_long_name_to_describe_what_it_does_enterprise_style,
+    )  # type: Tuple[int, int]
+
+    a = (
+        element
+        + another_element
+        + another_element_with_long_name
+        + element
+        + another_element
+        + another_element_with_long_name
+    )  # type: int
+
+
+def f(
+    x,  # not a type comment
+    y,  # type: int
+):
+    # type: (...) -> None
+    pass
+
+
+def f(
+    x,  # not a type comment
+):  # type: (int) -> None
+    pass
+
+
+def func(
+    a=some_list[0],  # type: int
+):  # type: () -> int
+    c = call(
+        0.0123,
+        0.0456,
+        0.0789,
+        0.0123,
+        0.0456,
+        0.0789,
+        0.0123,
+        0.0456,
+        0.0789,
+        a[-1],  # type: ignore
+    )
+
+    c = call(
+        "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa", "aaaaaaaa"  # type: ignore
+    )
+
+
+result = (  # aaa
+    "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+)
+
+AAAAAAAAAAAAA = [AAAAAAAAAAAAA] + SHARED_AAAAAAAAAAAAA + USER_AAAAAAAAAAAAA + AAAAAAAAAAAAA  # type: ignore
+
+call_to_some_function_asdf(
+    foo,
+    [AAAAAAAAAAAAAAAAAAAAAAA, AAAAAAAAAAAAAAAAAAAAAAA, AAAAAAAAAAAAAAAAAAAAAAA, BBBBBBBBBBBB],  # type: ignore
+)
+
+aaaaaaaaaaaaa, bbbbbbbbb = map(list, map(itertools.chain.from_iterable, zip(*items)))  # type: ignore[arg-type]
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__comments9_py.snap

@@ -0,0 +1,629 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/comments9.py
+---
+## Input
+
+```py
+# Test for https://github.com/psf/black/issues/246.
+
+some = statement
+# This comment should be split from the statement above by two lines.
+def function():
+    pass
+
+
+some = statement
+# This multiline comments section
+# should be split from the statement
+# above by two lines.
+def function():
+    pass
+
+
+some = statement
+# This comment should be split from the statement above by two lines.
+async def async_function():
+    pass
+
+
+some = statement
+# This comment should be split from the statement above by two lines.
+class MyClass:
+    pass
+
+
+some = statement
+# This should be stick to the statement above
+
+# This should be split from the above by two lines
+class MyClassWithComplexLeadingComments:
+    pass
+
+
+class ClassWithDocstring:
+    """A docstring."""
+# Leading comment after a class with just a docstring
+class MyClassAfterAnotherClassWithDocstring:
+    pass
+
+
+some = statement
+# leading 1
+@deco1
+# leading 2
+# leading 2 extra
+@deco2(with_args=True)
+# leading 3
+@deco3
+# leading 4
+def decorated():
+    pass
+
+
+some = statement
+# leading 1
+@deco1
+# leading 2
+@deco2(with_args=True)
+
+# leading 3 that already has an empty line
+@deco3
+# leading 4
+def decorated_with_split_leading_comments():
+    pass
+
+
+some = statement
+# leading 1
+@deco1
+# leading 2
+@deco2(with_args=True)
+# leading 3
+@deco3
+
+# leading 4 that already has an empty line
+def decorated_with_split_leading_comments():
+    pass
+
+
+def main():
+    if a:
+        # Leading comment before inline function
+        def inline():
+            pass
+        # Another leading comment
+        def another_inline():
+            pass
+    else:
+        # More leading comments
+        def inline_after_else():
+            pass
+
+
+if a:
+    # Leading comment before "top-level inline" function
+    def top_level_quote_inline():
+        pass
+    # Another leading comment
+    def another_top_level_quote_inline_inline():
+        pass
+else:
+    # More leading comments
+    def top_level_quote_inline_after_else():
+        pass
+
+
+class MyClass:
+    # First method has no empty lines between bare class def.
+    # More comments.
+    def first_method(self):
+        pass
+
+
+# Regression test for https://github.com/psf/black/issues/3454.
+def foo():
+    pass
+    # Trailing comment that belongs to this function
+
+
+@decorator1
+@decorator2  # fmt: skip
+def bar():
+    pass
+
+
+# Regression test for https://github.com/psf/black/issues/3454.
+def foo():
+    pass
+    # Trailing comment that belongs to this function.
+    # NOTE this comment only has one empty line below, and the formatter
+    # should enforce two blank lines.
+
+@decorator1
+# A standalone comment
+def bar():
+    pass
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -35,9 +35,10 @@
+ 
+ 
+ some = statement
++
++
+ # This should be stick to the statement above
+ 
+-
+ # This should be split from the above by two lines
+ class MyClassWithComplexLeadingComments:
+     pass
+@@ -57,13 +58,13 @@
+ 
+ # leading 1
+ @deco1
+-# leading 2
++@# leading 2
+ # leading 2 extra
+-@deco2(with_args=True)
+-# leading 3
+-@deco3
+-# leading 4
++deco2(with_args=True)
++@# leading 3
++deco3
+ def decorated():
++    # leading 4
+     pass
+ 
+ 
+@@ -72,13 +73,12 @@
+ 
+ # leading 1
+ @deco1
+-# leading 2
+-@deco2(with_args=True)
+-
+-# leading 3 that already has an empty line
+-@deco3
+-# leading 4
++@# leading 2
++deco2(with_args=True)
++@# leading 3 that already has an empty line
++deco3
+ def decorated_with_split_leading_comments():
++    # leading 4
+     pass
+ 
+ 
+@@ -87,18 +87,18 @@
+ 
+ # leading 1
+ @deco1
+-# leading 2
+-@deco2(with_args=True)
+-# leading 3
+-@deco3
+-
+-# leading 4 that already has an empty line
++@# leading 2
++deco2(with_args=True)
++@# leading 3
++deco3
+ def decorated_with_split_leading_comments():
++    # leading 4 that already has an empty line
+     pass
+ 
+ 
+ def main():
+     if a:
++
+         # Leading comment before inline function
+         def inline():
+             pass
+@@ -108,12 +108,14 @@
+             pass
+ 
+     else:
++
+         # More leading comments
+         def inline_after_else():
+             pass
+ 
+ 
+ if a:
++
+     # Leading comment before "top-level inline" function
+     def top_level_quote_inline():
+         pass
+@@ -123,6 +125,7 @@
+         pass
+ 
+ else:
++
+     # More leading comments
+     def top_level_quote_inline_after_else():
+         pass
+@@ -138,9 +141,11 @@
+ # Regression test for https://github.com/psf/black/issues/3454.
+ def foo():
+     pass
+-    # Trailing comment that belongs to this function
+ 
+ 
++# Trailing comment that belongs to this function
++
++
+ @decorator1
+ @decorator2  # fmt: skip
+ def bar():
+@@ -150,12 +155,13 @@
+ # Regression test for https://github.com/psf/black/issues/3454.
+ def foo():
+     pass
+-    # Trailing comment that belongs to this function.
+-    # NOTE this comment only has one empty line below, and the formatter
+-    # should enforce two blank lines.
+ 
+ 
++# Trailing comment that belongs to this function.
++# NOTE this comment only has one empty line below, and the formatter
++# should enforce two blank lines.
++
+ @decorator1
+-# A standalone comment
+ def bar():
+-    pass
+\ No newline at end of file
++    # A standalone comment
++    pass
+
+```
+
+## Ruff Output
+
+```py
+# Test for https://github.com/psf/black/issues/246.
+
+some = statement
+
+
+# This comment should be split from the statement above by two lines.
+def function():
+    pass
+
+
+some = statement
+
+
+# This multiline comments section
+# should be split from the statement
+# above by two lines.
+def function():
+    pass
+
+
+some = statement
+
+
+# This comment should be split from the statement above by two lines.
+async def async_function():
+    pass
+
+
+some = statement
+
+
+# This comment should be split from the statement above by two lines.
+class MyClass:
+    pass
+
+
+some = statement
+
+
+# This should be stick to the statement above
+
+# This should be split from the above by two lines
+class MyClassWithComplexLeadingComments:
+    pass
+
+
+class ClassWithDocstring:
+    """A docstring."""
+
+
+# Leading comment after a class with just a docstring
+class MyClassAfterAnotherClassWithDocstring:
+    pass
+
+
+some = statement
+
+
+# leading 1
+@deco1
+@# leading 2
+# leading 2 extra
+deco2(with_args=True)
+@# leading 3
+deco3
+def decorated():
+    # leading 4
+    pass
+
+
+some = statement
+
+
+# leading 1
+@deco1
+@# leading 2
+deco2(with_args=True)
+@# leading 3 that already has an empty line
+deco3
+def decorated_with_split_leading_comments():
+    # leading 4
+    pass
+
+
+some = statement
+
+
+# leading 1
+@deco1
+@# leading 2
+deco2(with_args=True)
+@# leading 3
+deco3
+def decorated_with_split_leading_comments():
+    # leading 4 that already has an empty line
+    pass
+
+
+def main():
+    if a:
+
+        # Leading comment before inline function
+        def inline():
+            pass
+
+        # Another leading comment
+        def another_inline():
+            pass
+
+    else:
+
+        # More leading comments
+        def inline_after_else():
+            pass
+
+
+if a:
+
+    # Leading comment before "top-level inline" function
+    def top_level_quote_inline():
+        pass
+
+    # Another leading comment
+    def another_top_level_quote_inline_inline():
+        pass
+
+else:
+
+    # More leading comments
+    def top_level_quote_inline_after_else():
+        pass
+
+
+class MyClass:
+    # First method has no empty lines between bare class def.
+    # More comments.
+    def first_method(self):
+        pass
+
+
+# Regression test for https://github.com/psf/black/issues/3454.
+def foo():
+    pass
+
+
+# Trailing comment that belongs to this function
+
+
+@decorator1
+@decorator2  # fmt: skip
+def bar():
+    pass
+
+
+# Regression test for https://github.com/psf/black/issues/3454.
+def foo():
+    pass
+
+
+# Trailing comment that belongs to this function.
+# NOTE this comment only has one empty line below, and the formatter
+# should enforce two blank lines.
+
+@decorator1
+def bar():
+    # A standalone comment
+    pass
+
+```
+
+## Black Output
+
+```py
+# Test for https://github.com/psf/black/issues/246.
+
+some = statement
+
+
+# This comment should be split from the statement above by two lines.
+def function():
+    pass
+
+
+some = statement
+
+
+# This multiline comments section
+# should be split from the statement
+# above by two lines.
+def function():
+    pass
+
+
+some = statement
+
+
+# This comment should be split from the statement above by two lines.
+async def async_function():
+    pass
+
+
+some = statement
+
+
+# This comment should be split from the statement above by two lines.
+class MyClass:
+    pass
+
+
+some = statement
+# This should be stick to the statement above
+
+
+# This should be split from the above by two lines
+class MyClassWithComplexLeadingComments:
+    pass
+
+
+class ClassWithDocstring:
+    """A docstring."""
+
+
+# Leading comment after a class with just a docstring
+class MyClassAfterAnotherClassWithDocstring:
+    pass
+
+
+some = statement
+
+
+# leading 1
+@deco1
+# leading 2
+# leading 2 extra
+@deco2(with_args=True)
+# leading 3
+@deco3
+# leading 4
+def decorated():
+    pass
+
+
+some = statement
+
+
+# leading 1
+@deco1
+# leading 2
+@deco2(with_args=True)
+
+# leading 3 that already has an empty line
+@deco3
+# leading 4
+def decorated_with_split_leading_comments():
+    pass
+
+
+some = statement
+
+
+# leading 1
+@deco1
+# leading 2
+@deco2(with_args=True)
+# leading 3
+@deco3
+
+# leading 4 that already has an empty line
+def decorated_with_split_leading_comments():
+    pass
+
+
+def main():
+    if a:
+        # Leading comment before inline function
+        def inline():
+            pass
+
+        # Another leading comment
+        def another_inline():
+            pass
+
+    else:
+        # More leading comments
+        def inline_after_else():
+            pass
+
+
+if a:
+    # Leading comment before "top-level inline" function
+    def top_level_quote_inline():
+        pass
+
+    # Another leading comment
+    def another_top_level_quote_inline_inline():
+        pass
+
+else:
+    # More leading comments
+    def top_level_quote_inline_after_else():
+        pass
+
+
+class MyClass:
+    # First method has no empty lines between bare class def.
+    # More comments.
+    def first_method(self):
+        pass
+
+
+# Regression test for https://github.com/psf/black/issues/3454.
+def foo():
+    pass
+    # Trailing comment that belongs to this function
+
+
+@decorator1
+@decorator2  # fmt: skip
+def bar():
+    pass
+
+
+# Regression test for https://github.com/psf/black/issues/3454.
+def foo():
+    pass
+    # Trailing comment that belongs to this function.
+    # NOTE this comment only has one empty line below, and the formatter
+    # should enforce two blank lines.
+
+
+@decorator1
+# A standalone comment
+def bar():
+    pass
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__composition_no_trailing_comma_py.snap

@@ -0,0 +1,882 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/composition_no_trailing_comma.py
+---
+## Input
+
+```py
+class C:
+    def test(self) -> None:
+        with patch("black.out", print):
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 1 file failed to reformat."
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file left unchanged, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 1 file left unchanged, 1 file failed to"
+                " reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
+            )
+            for i in (a,):
+                if (
+                    # Rule 1
+                    i % 2 == 0
+                    # Rule 2
+                    and i % 3 == 0
+                ):
+                    while (
+                        # Just a comment
+                        call()
+                        # Another
+                    ):
+                        print(i)
+        xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+            push_manager=context.request.resource_manager,
+            max_items_to_push=num_items,
+            batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE
+        ).push(
+            # Only send the first n items.
+            items=items[:num_items]
+        )
+        return (
+            'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+            % (test.name, test.filename, lineno, lname, err)
+        )
+
+    def omitting_trailers(self) -> None:
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex]
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+        d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+            22
+        ]
+        assignment = (
+            some.rather.elaborate.rule() and another.rule.ending_with.index[123]
+        )
+
+    def easy_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9
+        } == expected, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9
+        }
+
+    def tricky_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9
+        } == expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ), "Not what we expected"
+
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9
+        } == expected, (
+            "Not what we expected and the message is too long to fit in one line"
+        )
+
+        assert expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ) == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9
+        }, (
+            "Not what we expected and the message is too long to fit in one line"
+            " because it's too long"
+        )
+
+        dis_c_instance_method = """\
+        %3d           0 LOAD_FAST                1 (x)
+                      2 LOAD_CONST               1 (1)
+                      4 COMPARE_OP               2 (==)
+                      6 LOAD_FAST                0 (self)
+                      8 STORE_ATTR               0 (x)
+                     10 LOAD_CONST               0 (None)
+                     12 RETURN_VALUE
+        """ % (
+            _C.__init__.__code__.co_firstlineno + 1,
+        )
+
+        assert (
+            expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9
+            }
+        )
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -2,7 +2,8 @@
+     def test(self) -> None:
+         with patch("black.out", print):
+             self.assertEqual(
+-                unstyle(str(report)), "1 file reformatted, 1 file failed to reformat."
++                unstyle(str(report)),
++                "1 file reformatted, 1 file failed to reformat.",
+             )
+             self.assertEqual(
+                 unstyle(str(report)),
+@@ -22,133 +23,156 @@
+                 if (
+                     # Rule 1
+                     i % 2 == 0
+-                    # Rule 2
+-                    and i % 3 == 0
++                    and # Rule 2
++                    i % 3
++                    == 0
+                 ):
+-                    while (
+-                        # Just a comment
+-                        call()
++                    while # Just a comment
++                    call():
+                         # Another
+-                    ):
+                         print(i)
+         xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+             push_manager=context.request.resource_manager,
+             max_items_to_push=num_items,
+             batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE,
+         ).push(
+-            # Only send the first n items.
+-            items=items[:num_items]
++            items=# Only send the first n items.
++            items[:num_items]
+         )
+-        return (
+-            'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+-            % (test.name, test.filename, lineno, lname, err)
+-        )
++        return 'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
++        % (test.name, test.filename, lineno, lname, err)
+ 
+     def omitting_trailers(self) -> None:
+         get_collection(
+-            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
++            hey_this_is_a_very_long_call,
++            it_has_funny_attributes,
++            really=True,
+         )[OneLevelIndex]
+         get_collection(
+-            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
++            hey_this_is_a_very_long_call,
++            it_has_funny_attributes,
++            really=True,
+         )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+         d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+             22
+         ]
+-        assignment = (
+-            some.rather.elaborate.rule() and another.rule.ending_with.index[123]
+-        )
++        assignment = some.rather.elaborate.rule()
++        and another.rule.ending_with.index[123]
+ 
+     def easy_asserts(self) -> None:
+-        assert {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        } == expected, "Not what we expected"
++        assert (
++            {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++            == expected
++        ), "Not what we expected"
+ 
+-        assert expected == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }, "Not what we expected"
++        assert (
++            expected
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        ), "Not what we expected"
+ 
+-        assert expected == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }
++        assert (
++            expected
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        )
+ 
+     def tricky_asserts(self) -> None:
+-        assert {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        } == expected(
+-            value, is_going_to_be="too long to fit in a single line", srsly=True
++        assert (
++            {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++            == expected(
++                value,
++                is_going_to_be="too long to fit in a single line",
++                srsly=True,
++            )
+         ), "Not what we expected"
+ 
+-        assert {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        } == expected, (
+-            "Not what we expected and the message is too long to fit in one line"
+-        )
++        assert (
++            {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++            == expected
++        ), "Not what we expected and the message is too long to fit in one line"
+ 
+-        assert expected(
+-            value, is_going_to_be="too long to fit in a single line", srsly=True
+-        ) == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }, "Not what we expected"
++        assert (
++            expected(
++                value,
++                is_going_to_be="too long to fit in a single line",
++                srsly=True,
++            )
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        ), "Not what we expected"
+ 
+-        assert expected == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }, (
++        assert (
++            expected
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        ), (
+             "Not what we expected and the message is too long to fit in one line"
+             " because it's too long"
+         )
+@@ -161,9 +185,8 @@
+                       8 STORE_ATTR               0 (x)
+                      10 LOAD_CONST               0 (None)
+                      12 RETURN_VALUE
+-        """ % (
+-            _C.__init__.__code__.co_firstlineno + 1,
+-        )
++        """
++        % (_C.__init__.__code__.co_firstlineno + 1,)
+ 
+         assert (
+             expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+@@ -178,4 +201,4 @@
+                 key8: value8,
+                 key9: value9,
+             }
+-        )
+\ No newline at end of file
++        )
+
+```
+
+## Ruff Output
+
+```py
+class C:
+    def test(self) -> None:
+        with patch("black.out", print):
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file left unchanged, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 1 file left unchanged, 1 file failed to"
+                " reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
+            )
+            for i in (a,):
+                if (
+                    # Rule 1
+                    i % 2 == 0
+                    and # Rule 2
+                    i % 3
+                    == 0
+                ):
+                    while # Just a comment
+                    call():
+                        # Another
+                        print(i)
+        xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+            push_manager=context.request.resource_manager,
+            max_items_to_push=num_items,
+            batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE,
+        ).push(
+            items=# Only send the first n items.
+            items[:num_items]
+        )
+        return 'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+        % (test.name, test.filename, lineno, lname, err)
+
+    def omitting_trailers(self) -> None:
+        get_collection(
+            hey_this_is_a_very_long_call,
+            it_has_funny_attributes,
+            really=True,
+        )[OneLevelIndex]
+        get_collection(
+            hey_this_is_a_very_long_call,
+            it_has_funny_attributes,
+            really=True,
+        )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+        d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+            22
+        ]
+        assignment = some.rather.elaborate.rule()
+        and another.rule.ending_with.index[123]
+
+    def easy_asserts(self) -> None:
+        assert (
+            {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+            == expected
+        ), "Not what we expected"
+
+        assert (
+            expected
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        ), "Not what we expected"
+
+        assert (
+            expected
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        )
+
+    def tricky_asserts(self) -> None:
+        assert (
+            {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+            == expected(
+                value,
+                is_going_to_be="too long to fit in a single line",
+                srsly=True,
+            )
+        ), "Not what we expected"
+
+        assert (
+            {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+            == expected
+        ), "Not what we expected and the message is too long to fit in one line"
+
+        assert (
+            expected(
+                value,
+                is_going_to_be="too long to fit in a single line",
+                srsly=True,
+            )
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        ), "Not what we expected"
+
+        assert (
+            expected
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        ), (
+            "Not what we expected and the message is too long to fit in one line"
+            " because it's too long"
+        )
+
+        dis_c_instance_method = """\
+        %3d           0 LOAD_FAST                1 (x)
+                      2 LOAD_CONST               1 (1)
+                      4 COMPARE_OP               2 (==)
+                      6 LOAD_FAST                0 (self)
+                      8 STORE_ATTR               0 (x)
+                     10 LOAD_CONST               0 (None)
+                     12 RETURN_VALUE
+        """
+        % (_C.__init__.__code__.co_firstlineno + 1,)
+
+        assert (
+            expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        )
+
+```
+
+## Black Output
+
+```py
+class C:
+    def test(self) -> None:
+        with patch("black.out", print):
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 1 file failed to reformat."
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file left unchanged, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 1 file left unchanged, 1 file failed to"
+                " reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
+            )
+            for i in (a,):
+                if (
+                    # Rule 1
+                    i % 2 == 0
+                    # Rule 2
+                    and i % 3 == 0
+                ):
+                    while (
+                        # Just a comment
+                        call()
+                        # Another
+                    ):
+                        print(i)
+        xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+            push_manager=context.request.resource_manager,
+            max_items_to_push=num_items,
+            batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE,
+        ).push(
+            # Only send the first n items.
+            items=items[:num_items]
+        )
+        return (
+            'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+            % (test.name, test.filename, lineno, lname, err)
+        )
+
+    def omitting_trailers(self) -> None:
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex]
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+        d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+            22
+        ]
+        assignment = (
+            some.rather.elaborate.rule() and another.rule.ending_with.index[123]
+        )
+
+    def easy_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }
+
+    def tricky_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ), "Not what we expected"
+
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected, (
+            "Not what we expected and the message is too long to fit in one line"
+        )
+
+        assert expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ) == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, (
+            "Not what we expected and the message is too long to fit in one line"
+            " because it's too long"
+        )
+
+        dis_c_instance_method = """\
+        %3d           0 LOAD_FAST                1 (x)
+                      2 LOAD_CONST               1 (1)
+                      4 COMPARE_OP               2 (==)
+                      6 LOAD_FAST                0 (self)
+                      8 STORE_ATTR               0 (x)
+                     10 LOAD_CONST               0 (None)
+                     12 RETURN_VALUE
+        """ % (
+            _C.__init__.__code__.co_firstlineno + 1,
+        )
+
+        assert (
+            expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        )
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__composition_py.snap

@@ -0,0 +1,882 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/composition.py
+---
+## Input
+
+```py
+class C:
+    def test(self) -> None:
+        with patch("black.out", print):
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 1 file failed to reformat."
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file left unchanged, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 1 file left unchanged, 1 file failed to"
+                " reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
+            )
+            for i in (a,):
+                if (
+                    # Rule 1
+                    i % 2 == 0
+                    # Rule 2
+                    and i % 3 == 0
+                ):
+                    while (
+                        # Just a comment
+                        call()
+                        # Another
+                    ):
+                        print(i)
+        xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+            push_manager=context.request.resource_manager,
+            max_items_to_push=num_items,
+            batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE,
+        ).push(
+            # Only send the first n items.
+            items=items[:num_items]
+        )
+        return (
+            'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+            % (test.name, test.filename, lineno, lname, err)
+        )
+
+    def omitting_trailers(self) -> None:
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex]
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+        d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+            22
+        ]
+        assignment = (
+            some.rather.elaborate.rule() and another.rule.ending_with.index[123]
+        )
+
+    def easy_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }
+
+    def tricky_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ), "Not what we expected"
+
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected, (
+            "Not what we expected and the message is too long to fit in one line"
+        )
+
+        assert expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ) == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, (
+            "Not what we expected and the message is too long to fit in one line"
+            " because it's too long"
+        )
+
+        dis_c_instance_method = """\
+        %3d           0 LOAD_FAST                1 (x)
+                      2 LOAD_CONST               1 (1)
+                      4 COMPARE_OP               2 (==)
+                      6 LOAD_FAST                0 (self)
+                      8 STORE_ATTR               0 (x)
+                     10 LOAD_CONST               0 (None)
+                     12 RETURN_VALUE
+        """ % (
+            _C.__init__.__code__.co_firstlineno + 1,
+        )
+
+        assert (
+            expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        )
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -2,7 +2,8 @@
+     def test(self) -> None:
+         with patch("black.out", print):
+             self.assertEqual(
+-                unstyle(str(report)), "1 file reformatted, 1 file failed to reformat."
++                unstyle(str(report)),
++                "1 file reformatted, 1 file failed to reformat.",
+             )
+             self.assertEqual(
+                 unstyle(str(report)),
+@@ -22,133 +23,156 @@
+                 if (
+                     # Rule 1
+                     i % 2 == 0
+-                    # Rule 2
+-                    and i % 3 == 0
++                    and # Rule 2
++                    i % 3
++                    == 0
+                 ):
+-                    while (
+-                        # Just a comment
+-                        call()
++                    while # Just a comment
++                    call():
+                         # Another
+-                    ):
+                         print(i)
+         xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+             push_manager=context.request.resource_manager,
+             max_items_to_push=num_items,
+             batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE,
+         ).push(
+-            # Only send the first n items.
+-            items=items[:num_items]
++            items=# Only send the first n items.
++            items[:num_items]
+         )
+-        return (
+-            'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+-            % (test.name, test.filename, lineno, lname, err)
+-        )
++        return 'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
++        % (test.name, test.filename, lineno, lname, err)
+ 
+     def omitting_trailers(self) -> None:
+         get_collection(
+-            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
++            hey_this_is_a_very_long_call,
++            it_has_funny_attributes,
++            really=True,
+         )[OneLevelIndex]
+         get_collection(
+-            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
++            hey_this_is_a_very_long_call,
++            it_has_funny_attributes,
++            really=True,
+         )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+         d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+             22
+         ]
+-        assignment = (
+-            some.rather.elaborate.rule() and another.rule.ending_with.index[123]
+-        )
++        assignment = some.rather.elaborate.rule()
++        and another.rule.ending_with.index[123]
+ 
+     def easy_asserts(self) -> None:
+-        assert {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        } == expected, "Not what we expected"
++        assert (
++            {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++            == expected
++        ), "Not what we expected"
+ 
+-        assert expected == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }, "Not what we expected"
++        assert (
++            expected
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        ), "Not what we expected"
+ 
+-        assert expected == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }
++        assert (
++            expected
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        )
+ 
+     def tricky_asserts(self) -> None:
+-        assert {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        } == expected(
+-            value, is_going_to_be="too long to fit in a single line", srsly=True
++        assert (
++            {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++            == expected(
++                value,
++                is_going_to_be="too long to fit in a single line",
++                srsly=True,
++            )
+         ), "Not what we expected"
+ 
+-        assert {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        } == expected, (
+-            "Not what we expected and the message is too long to fit in one line"
+-        )
++        assert (
++            {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++            == expected
++        ), "Not what we expected and the message is too long to fit in one line"
+ 
+-        assert expected(
+-            value, is_going_to_be="too long to fit in a single line", srsly=True
+-        ) == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }, "Not what we expected"
++        assert (
++            expected(
++                value,
++                is_going_to_be="too long to fit in a single line",
++                srsly=True,
++            )
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        ), "Not what we expected"
+ 
+-        assert expected == {
+-            key1: value1,
+-            key2: value2,
+-            key3: value3,
+-            key4: value4,
+-            key5: value5,
+-            key6: value6,
+-            key7: value7,
+-            key8: value8,
+-            key9: value9,
+-        }, (
++        assert (
++            expected
++            == {
++                key1: value1,
++                key2: value2,
++                key3: value3,
++                key4: value4,
++                key5: value5,
++                key6: value6,
++                key7: value7,
++                key8: value8,
++                key9: value9,
++            }
++        ), (
+             "Not what we expected and the message is too long to fit in one line"
+             " because it's too long"
+         )
+@@ -161,9 +185,8 @@
+                       8 STORE_ATTR               0 (x)
+                      10 LOAD_CONST               0 (None)
+                      12 RETURN_VALUE
+-        """ % (
+-            _C.__init__.__code__.co_firstlineno + 1,
+-        )
++        """
++        % (_C.__init__.__code__.co_firstlineno + 1,)
+ 
+         assert (
+             expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+@@ -178,4 +201,4 @@
+                 key8: value8,
+                 key9: value9,
+             }
+-        )
+\ No newline at end of file
++        )
+
+```
+
+## Ruff Output
+
+```py
+class C:
+    def test(self) -> None:
+        with patch("black.out", print):
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file left unchanged, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 1 file left unchanged, 1 file failed to"
+                " reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
+            )
+            for i in (a,):
+                if (
+                    # Rule 1
+                    i % 2 == 0
+                    and # Rule 2
+                    i % 3
+                    == 0
+                ):
+                    while # Just a comment
+                    call():
+                        # Another
+                        print(i)
+        xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+            push_manager=context.request.resource_manager,
+            max_items_to_push=num_items,
+            batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE,
+        ).push(
+            items=# Only send the first n items.
+            items[:num_items]
+        )
+        return 'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+        % (test.name, test.filename, lineno, lname, err)
+
+    def omitting_trailers(self) -> None:
+        get_collection(
+            hey_this_is_a_very_long_call,
+            it_has_funny_attributes,
+            really=True,
+        )[OneLevelIndex]
+        get_collection(
+            hey_this_is_a_very_long_call,
+            it_has_funny_attributes,
+            really=True,
+        )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+        d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+            22
+        ]
+        assignment = some.rather.elaborate.rule()
+        and another.rule.ending_with.index[123]
+
+    def easy_asserts(self) -> None:
+        assert (
+            {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+            == expected
+        ), "Not what we expected"
+
+        assert (
+            expected
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        ), "Not what we expected"
+
+        assert (
+            expected
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        )
+
+    def tricky_asserts(self) -> None:
+        assert (
+            {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+            == expected(
+                value,
+                is_going_to_be="too long to fit in a single line",
+                srsly=True,
+            )
+        ), "Not what we expected"
+
+        assert (
+            {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+            == expected
+        ), "Not what we expected and the message is too long to fit in one line"
+
+        assert (
+            expected(
+                value,
+                is_going_to_be="too long to fit in a single line",
+                srsly=True,
+            )
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        ), "Not what we expected"
+
+        assert (
+            expected
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        ), (
+            "Not what we expected and the message is too long to fit in one line"
+            " because it's too long"
+        )
+
+        dis_c_instance_method = """\
+        %3d           0 LOAD_FAST                1 (x)
+                      2 LOAD_CONST               1 (1)
+                      4 COMPARE_OP               2 (==)
+                      6 LOAD_FAST                0 (self)
+                      8 STORE_ATTR               0 (x)
+                     10 LOAD_CONST               0 (None)
+                     12 RETURN_VALUE
+        """
+        % (_C.__init__.__code__.co_firstlineno + 1,)
+
+        assert (
+            expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        )
+
+```
+
+## Black Output
+
+```py
+class C:
+    def test(self) -> None:
+        with patch("black.out", print):
+            self.assertEqual(
+                unstyle(str(report)), "1 file reformatted, 1 file failed to reformat."
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "1 file reformatted, 1 file left unchanged, 1 file failed to reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 1 file left unchanged, 1 file failed to"
+                " reformat.",
+            )
+            self.assertEqual(
+                unstyle(str(report)),
+                "2 files reformatted, 2 files left unchanged, 2 files failed to"
+                " reformat.",
+            )
+            for i in (a,):
+                if (
+                    # Rule 1
+                    i % 2 == 0
+                    # Rule 2
+                    and i % 3 == 0
+                ):
+                    while (
+                        # Just a comment
+                        call()
+                        # Another
+                    ):
+                        print(i)
+        xxxxxxxxxxxxxxxx = Yyyy2YyyyyYyyyyy(
+            push_manager=context.request.resource_manager,
+            max_items_to_push=num_items,
+            batch_size=Yyyy2YyyyYyyyyYyyy.FULL_SIZE,
+        ).push(
+            # Only send the first n items.
+            items=items[:num_items]
+        )
+        return (
+            'Utterly failed doctest test for %s\n   File "%s", line %s, in %s\n\n%s'
+            % (test.name, test.filename, lineno, lname, err)
+        )
+
+    def omitting_trailers(self) -> None:
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex]
+        get_collection(
+            hey_this_is_a_very_long_call, it_has_funny_attributes, really=True
+        )[OneLevelIndex][TwoLevelIndex][ThreeLevelIndex][FourLevelIndex]
+        d[0][1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][
+            22
+        ]
+        assignment = (
+            some.rather.elaborate.rule() and another.rule.ending_with.index[123]
+        )
+
+    def easy_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }
+
+    def tricky_asserts(self) -> None:
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ), "Not what we expected"
+
+        assert {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        } == expected, (
+            "Not what we expected and the message is too long to fit in one line"
+        )
+
+        assert expected(
+            value, is_going_to_be="too long to fit in a single line", srsly=True
+        ) == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, "Not what we expected"
+
+        assert expected == {
+            key1: value1,
+            key2: value2,
+            key3: value3,
+            key4: value4,
+            key5: value5,
+            key6: value6,
+            key7: value7,
+            key8: value8,
+            key9: value9,
+        }, (
+            "Not what we expected and the message is too long to fit in one line"
+            " because it's too long"
+        )
+
+        dis_c_instance_method = """\
+        %3d           0 LOAD_FAST                1 (x)
+                      2 LOAD_CONST               1 (1)
+                      4 COMPARE_OP               2 (==)
+                      6 LOAD_FAST                0 (self)
+                      8 STORE_ATTR               0 (x)
+                     10 LOAD_CONST               0 (None)
+                     12 RETURN_VALUE
+        """ % (
+            _C.__init__.__code__.co_firstlineno + 1,
+        )
+
+        assert (
+            expectedexpectedexpectedexpectedexpectedexpectedexpectedexpectedexpect
+            == {
+                key1: value1,
+                key2: value2,
+                key3: value3,
+                key4: value4,
+                key5: value5,
+                key6: value6,
+                key7: value7,
+                key8: value8,
+                key9: value9,
+            }
+        )
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__docstring_no_extra_empty_line_before_eof_py.snap

@@ -0,0 +1,50 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/docstring_no_extra_empty_line_before_eof.py
+---
+## Input
+
+```py
+# Make sure when the file ends with class's docstring,
+# It doesn't add extra blank lines.
+class ClassWithDocstring:
+    """A docstring."""
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,4 +1,4 @@
+ # Make sure when the file ends with class's docstring,
+ # It doesn't add extra blank lines.
+ class ClassWithDocstring:
+-    """A docstring."""
+\ No newline at end of file
++    """A docstring."""
+
+```
+
+## Ruff Output
+
+```py
+# Make sure when the file ends with class's docstring,
+# It doesn't add extra blank lines.
+class ClassWithDocstring:
+    """A docstring."""
+
+```
+
+## Black Output
+
+```py
+# Make sure when the file ends with class's docstring,
+# It doesn't add extra blank lines.
+class ClassWithDocstring:
+    """A docstring."""
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__empty_lines_py.snap

@@ -0,0 +1,419 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/empty_lines.py
+---
+## Input
+
+```py
+"""Docstring."""
+
+
+# leading comment
+def f():
+    NO = ''
+    SPACE = ' '
+    DOUBLESPACE = '  '
+
+    t = leaf.type
+    p = leaf.parent  # trailing comment
+    v = leaf.value
+
+    if t in ALWAYS_NO_SPACE:
+        pass
+    if t == token.COMMENT:  # another trailing comment
+        return DOUBLESPACE
+
+
+    assert p is not None, f"INTERNAL ERROR: hand-made leaf without parent: {leaf!r}"
+
+
+    prev = leaf.prev_sibling
+    if not prev:
+        prevp = preceding_leaf(p)
+        if not prevp or prevp.type in OPENING_BRACKETS:
+
+
+            return NO
+
+
+        if prevp.type == token.EQUAL:
+            if prevp.parent and prevp.parent.type in {
+                syms.typedargslist,
+                syms.varargslist,
+                syms.parameters,
+                syms.arglist,
+                syms.argument,
+            }:
+                return NO
+
+        elif prevp.type == token.DOUBLESTAR:
+            if prevp.parent and prevp.parent.type in {
+                syms.typedargslist,
+                syms.varargslist,
+                syms.parameters,
+                syms.arglist,
+                syms.dictsetmaker,
+            }:
+                return NO
+
+###############################################################################
+# SECTION BECAUSE SECTIONS
+###############################################################################
+
+def g():
+    NO = ''
+    SPACE = ' '
+    DOUBLESPACE = '  '
+
+    t = leaf.type
+    p = leaf.parent
+    v = leaf.value
+
+    # Comment because comments
+
+    if t in ALWAYS_NO_SPACE:
+        pass
+    if t == token.COMMENT:
+        return DOUBLESPACE
+
+    # Another comment because more comments
+    assert p is not None, f'INTERNAL ERROR: hand-made leaf without parent: {leaf!r}'
+
+    prev = leaf.prev_sibling
+    if not prev:
+        prevp = preceding_leaf(p)
+
+        if not prevp or prevp.type in OPENING_BRACKETS:
+            # Start of the line or a bracketed expression.
+            # More than one line for the comment.
+            return NO
+
+        if prevp.type == token.EQUAL:
+            if prevp.parent and prevp.parent.type in {
+                syms.typedargslist,
+                syms.varargslist,
+                syms.parameters,
+                syms.arglist,
+                syms.argument,
+            }:
+                return NO
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -3,9 +3,9 @@
+ 
+ # leading comment
+ def f():
+-    NO = ""
+-    SPACE = " "
+-    DOUBLESPACE = "  "
++    NO = ''
++    SPACE = ' '
++    DOUBLESPACE = '  '
+ 
+     t = leaf.type
+     p = leaf.parent  # trailing comment
+@@ -25,23 +25,30 @@
+             return NO
+ 
+         if prevp.type == token.EQUAL:
+-            if prevp.parent and prevp.parent.type in {
+-                syms.typedargslist,
+-                syms.varargslist,
+-                syms.parameters,
+-                syms.arglist,
+-                syms.argument,
+-            }:
++            if (
++                prevp.parent
++                and prevp.parent.type
++                in {
++                    syms.typedargslist,
++                    syms.varargslist,
++                    syms.parameters,
++                    syms.arglist,
++                    syms.argument,
++                }
++            ):
+                 return NO
+-
+         elif prevp.type == token.DOUBLESTAR:
+-            if prevp.parent and prevp.parent.type in {
+-                syms.typedargslist,
+-                syms.varargslist,
+-                syms.parameters,
+-                syms.arglist,
+-                syms.dictsetmaker,
+-            }:
++            if (
++                prevp.parent
++                and prevp.parent.type
++                in {
++                    syms.typedargslist,
++                    syms.varargslist,
++                    syms.parameters,
++                    syms.arglist,
++                    syms.dictsetmaker,
++                }
++            ):
+                 return NO
+ 
+ 
+@@ -49,11 +56,10 @@
+ # SECTION BECAUSE SECTIONS
+ ###############################################################################
+ 
+-
+ def g():
+-    NO = ""
+-    SPACE = " "
+-    DOUBLESPACE = "  "
++    NO = ''
++    SPACE = ' '
++    DOUBLESPACE = '  '
+ 
+     t = leaf.type
+     p = leaf.parent
+@@ -67,7 +73,7 @@
+         return DOUBLESPACE
+ 
+     # Another comment because more comments
+-    assert p is not None, f"INTERNAL ERROR: hand-made leaf without parent: {leaf!r}"
++    assert p is not None, f'INTERNAL ERROR: hand-made leaf without parent: {leaf!r}'
+ 
+     prev = leaf.prev_sibling
+     if not prev:
+@@ -79,11 +85,15 @@
+             return NO
+ 
+         if prevp.type == token.EQUAL:
+-            if prevp.parent and prevp.parent.type in {
+-                syms.typedargslist,
+-                syms.varargslist,
+-                syms.parameters,
+-                syms.arglist,
+-                syms.argument,
+-            }:
+-                return NO
+\ No newline at end of file
++            if (
++                prevp.parent
++                and prevp.parent.type
++                in {
++                    syms.typedargslist,
++                    syms.varargslist,
++                    syms.parameters,
++                    syms.arglist,
++                    syms.argument,
++                }
++            ):
++                return NO
+
+```
+
+## Ruff Output
+
+```py
+"""Docstring."""
+
+
+# leading comment
+def f():
+    NO = ''
+    SPACE = ' '
+    DOUBLESPACE = '  '
+
+    t = leaf.type
+    p = leaf.parent  # trailing comment
+    v = leaf.value
+
+    if t in ALWAYS_NO_SPACE:
+        pass
+    if t == token.COMMENT:  # another trailing comment
+        return DOUBLESPACE
+
+    assert p is not None, f"INTERNAL ERROR: hand-made leaf without parent: {leaf!r}"
+
+    prev = leaf.prev_sibling
+    if not prev:
+        prevp = preceding_leaf(p)
+        if not prevp or prevp.type in OPENING_BRACKETS:
+            return NO
+
+        if prevp.type == token.EQUAL:
+            if (
+                prevp.parent
+                and prevp.parent.type
+                in {
+                    syms.typedargslist,
+                    syms.varargslist,
+                    syms.parameters,
+                    syms.arglist,
+                    syms.argument,
+                }
+            ):
+                return NO
+        elif prevp.type == token.DOUBLESTAR:
+            if (
+                prevp.parent
+                and prevp.parent.type
+                in {
+                    syms.typedargslist,
+                    syms.varargslist,
+                    syms.parameters,
+                    syms.arglist,
+                    syms.dictsetmaker,
+                }
+            ):
+                return NO
+
+
+###############################################################################
+# SECTION BECAUSE SECTIONS
+###############################################################################
+
+def g():
+    NO = ''
+    SPACE = ' '
+    DOUBLESPACE = '  '
+
+    t = leaf.type
+    p = leaf.parent
+    v = leaf.value
+
+    # Comment because comments
+
+    if t in ALWAYS_NO_SPACE:
+        pass
+    if t == token.COMMENT:
+        return DOUBLESPACE
+
+    # Another comment because more comments
+    assert p is not None, f'INTERNAL ERROR: hand-made leaf without parent: {leaf!r}'
+
+    prev = leaf.prev_sibling
+    if not prev:
+        prevp = preceding_leaf(p)
+
+        if not prevp or prevp.type in OPENING_BRACKETS:
+            # Start of the line or a bracketed expression.
+            # More than one line for the comment.
+            return NO
+
+        if prevp.type == token.EQUAL:
+            if (
+                prevp.parent
+                and prevp.parent.type
+                in {
+                    syms.typedargslist,
+                    syms.varargslist,
+                    syms.parameters,
+                    syms.arglist,
+                    syms.argument,
+                }
+            ):
+                return NO
+
+```
+
+## Black Output
+
+```py
+"""Docstring."""
+
+
+# leading comment
+def f():
+    NO = ""
+    SPACE = " "
+    DOUBLESPACE = "  "
+
+    t = leaf.type
+    p = leaf.parent  # trailing comment
+    v = leaf.value
+
+    if t in ALWAYS_NO_SPACE:
+        pass
+    if t == token.COMMENT:  # another trailing comment
+        return DOUBLESPACE
+
+    assert p is not None, f"INTERNAL ERROR: hand-made leaf without parent: {leaf!r}"
+
+    prev = leaf.prev_sibling
+    if not prev:
+        prevp = preceding_leaf(p)
+        if not prevp or prevp.type in OPENING_BRACKETS:
+            return NO
+
+        if prevp.type == token.EQUAL:
+            if prevp.parent and prevp.parent.type in {
+                syms.typedargslist,
+                syms.varargslist,
+                syms.parameters,
+                syms.arglist,
+                syms.argument,
+            }:
+                return NO
+
+        elif prevp.type == token.DOUBLESTAR:
+            if prevp.parent and prevp.parent.type in {
+                syms.typedargslist,
+                syms.varargslist,
+                syms.parameters,
+                syms.arglist,
+                syms.dictsetmaker,
+            }:
+                return NO
+
+
+###############################################################################
+# SECTION BECAUSE SECTIONS
+###############################################################################
+
+
+def g():
+    NO = ""
+    SPACE = " "
+    DOUBLESPACE = "  "
+
+    t = leaf.type
+    p = leaf.parent
+    v = leaf.value
+
+    # Comment because comments
+
+    if t in ALWAYS_NO_SPACE:
+        pass
+    if t == token.COMMENT:
+        return DOUBLESPACE
+
+    # Another comment because more comments
+    assert p is not None, f"INTERNAL ERROR: hand-made leaf without parent: {leaf!r}"
+
+    prev = leaf.prev_sibling
+    if not prev:
+        prevp = preceding_leaf(p)
+
+        if not prevp or prevp.type in OPENING_BRACKETS:
+            # Start of the line or a bracketed expression.
+            # More than one line for the comment.
+            return NO
+
+        if prevp.type == token.EQUAL:
+            if prevp.parent and prevp.parent.type in {
+                syms.typedargslist,
+                syms.varargslist,
+                syms.parameters,
+                syms.arglist,
+                syms.argument,
+            }:
+                return NO
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtonoff2_py.snap

@@ -0,0 +1,210 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff2.py
+---
+## Input
+
+```py
+import pytest
+
+TmSt = 1
+TmEx = 2
+
+# fmt: off
+
+# Test data:
+#   Position, Volume, State, TmSt/TmEx/None, [call, [arg1...]]
+
+@pytest.mark.parametrize('test', [
+
+    # Test don't manage the volume
+    [
+        ('stuff', 'in')
+    ],
+])
+def test_fader(test):
+    pass
+
+def check_fader(test):
+
+    pass
+
+def verify_fader(test):
+  # misaligned comment
+    pass
+
+def verify_fader(test):
+    """Hey, ho."""
+    assert test.passed()
+
+def test_calculate_fades():
+    calcs = [
+        # one is zero/none
+        (0, 4, 0, 0, 10,        0, 0, 6, 10),
+        (None, 4, 0, 0, 10,     0, 0, 6, 10),
+    ]
+
+# fmt: on
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -3,38 +3,42 @@
+ TmSt = 1
+ TmEx = 2
+ 
++
+ # fmt: off
+ 
+ # Test data:
+ #   Position, Volume, State, TmSt/TmEx/None, [call, [arg1...]]
+-
+-@pytest.mark.parametrize('test', [
+ 
+-    # Test don't manage the volume
++@pytest.mark.parametrize(
++    'test',
+     [
+-        ('stuff', 'in')
++        # Test don't manage the volume
++        [('stuff', 'in')],
+     ],
+-])
++)
+ def test_fader(test):
+     pass
+ 
++
+ def check_fader(test):
++    pass
+ 
+-    pass
+ 
+ def verify_fader(test):
+-  # misaligned comment
++    # misaligned comment
+     pass
+ 
++
+ def verify_fader(test):
+     """Hey, ho."""
+     assert test.passed()
+ 
++
+ def test_calculate_fades():
+     calcs = [
+-        # one is zero/none
+-        (0, 4, 0, 0, 10,        0, 0, 6, 10),
+-        (None, 4, 0, 0, 10,     0, 0, 6, 10),
++        (# one is zero/none
++        0, 4, 0, 0, 10, 0, 0, 6, 10),
++        (None, 4, 0, 0, 10, 0, 0, 6, 10),
+     ]
+ 
+-# fmt: on
+\ No newline at end of file
++# fmt: on
+
+```
+
+## Ruff Output
+
+```py
+import pytest
+
+TmSt = 1
+TmEx = 2
+
+
+# fmt: off
+
+# Test data:
+#   Position, Volume, State, TmSt/TmEx/None, [call, [arg1...]]
+
+@pytest.mark.parametrize(
+    'test',
+    [
+        # Test don't manage the volume
+        [('stuff', 'in')],
+    ],
+)
+def test_fader(test):
+    pass
+
+
+def check_fader(test):
+    pass
+
+
+def verify_fader(test):
+    # misaligned comment
+    pass
+
+
+def verify_fader(test):
+    """Hey, ho."""
+    assert test.passed()
+
+
+def test_calculate_fades():
+    calcs = [
+        (# one is zero/none
+        0, 4, 0, 0, 10, 0, 0, 6, 10),
+        (None, 4, 0, 0, 10, 0, 0, 6, 10),
+    ]
+
+# fmt: on
+
+```
+
+## Black Output
+
+```py
+import pytest
+
+TmSt = 1
+TmEx = 2
+
+# fmt: off
+
+# Test data:
+#   Position, Volume, State, TmSt/TmEx/None, [call, [arg1...]]
+
+@pytest.mark.parametrize('test', [
+
+    # Test don't manage the volume
+    [
+        ('stuff', 'in')
+    ],
+])
+def test_fader(test):
+    pass
+
+def check_fader(test):
+
+    pass
+
+def verify_fader(test):
+  # misaligned comment
+    pass
+
+def verify_fader(test):
+    """Hey, ho."""
+    assert test.passed()
+
+def test_calculate_fades():
+    calcs = [
+        # one is zero/none
+        (0, 4, 0, 0, 10,        0, 0, 6, 10),
+        (None, 4, 0, 0, 10,     0, 0, 6, 10),
+    ]
+
+# fmt: on
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtonoff3_py.snap

@@ -0,0 +1,104 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff3.py
+---
+## Input
+
+```py
+# fmt: off
+x = [
+    1, 2,
+    3, 4,
+]
+# fmt: on
+
+# fmt: off
+x = [
+    1, 2,
+    3, 4,
+]
+# fmt: on
+
+x = [
+    1, 2, 3, 4
+]
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,14 +1,18 @@
+ # fmt: off
+ x = [
+-    1, 2,
+-    3, 4,
++    1,
++    2,
++    3,
++    4,
+ ]
+ # fmt: on
+ 
+ # fmt: off
+ x = [
+-    1, 2,
+-    3, 4,
++    1,
++    2,
++    3,
++    4,
+ ]
+ # fmt: on
+ 
+
+```
+
+## Ruff Output
+
+```py
+# fmt: off
+x = [
+    1,
+    2,
+    3,
+    4,
+]
+# fmt: on
+
+# fmt: off
+x = [
+    1,
+    2,
+    3,
+    4,
+]
+# fmt: on
+
+x = [1, 2, 3, 4]
+```
+
+## Black Output
+
+```py
+# fmt: off
+x = [
+    1, 2,
+    3, 4,
+]
+# fmt: on
+
+# fmt: off
+x = [
+    1, 2,
+    3, 4,
+]
+# fmt: on
+
+x = [1, 2, 3, 4]
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtonoff4_py.snap

@@ -0,0 +1,115 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff4.py
+---
+## Input
+
+```py
+# fmt: off
+@test([
+    1, 2,
+    3, 4,
+])
+# fmt: on
+def f(): pass
+
+@test([
+    1, 2,
+    3, 4,
+])
+def f(): pass
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,10 +1,14 @@
+ # fmt: off
+-@test([
+-    1, 2,
+-    3, 4,
+-])
+-# fmt: on
++@test(
++    [
++        1,
++        2,
++        3,
++        4,
++    ]
++)
+ def f():
++    # fmt: on
+     pass
+ 
+ 
+@@ -17,4 +21,4 @@
+     ]
+ )
+ def f():
+-    pass
+\ No newline at end of file
++    pass
+
+```
+
+## Ruff Output
+
+```py
+# fmt: off
+@test(
+    [
+        1,
+        2,
+        3,
+        4,
+    ]
+)
+def f():
+    # fmt: on
+    pass
+
+
+@test(
+    [
+        1,
+        2,
+        3,
+        4,
+    ]
+)
+def f():
+    pass
+
+```
+
+## Black Output
+
+```py
+# fmt: off
+@test([
+    1, 2,
+    3, 4,
+])
+# fmt: on
+def f():
+    pass
+
+
+@test(
+    [
+        1,
+        2,
+        3,
+        4,
+    ]
+)
+def f():
+    pass
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtonoff5_py.snap

@@ -0,0 +1,378 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtonoff5.py
+---
+## Input
+
+```py
+# Regression test for https://github.com/psf/black/issues/3129.
+setup(
+    entry_points={
+        # fmt: off
+        "console_scripts": [
+            "foo-bar"
+            "=foo.bar.:main",
+        # fmt: on
+            ]  # Includes an formatted indentation.
+    },
+)
+
+
+# Regression test for https://github.com/psf/black/issues/2015.
+run(
+    # fmt: off
+    [
+        "ls",
+        "-la",
+    ]
+    # fmt: on
+    + path,
+    check=True,
+)
+
+
+# Regression test for https://github.com/psf/black/issues/3026.
+def test_func():
+    # yapf: disable
+    if  unformatted(  args  ):
+        return True
+    # yapf: enable
+    elif b:
+        return True
+
+    return False
+
+
+# Regression test for https://github.com/psf/black/issues/2567.
+if True:
+    # fmt: off
+    for _ in range( 1 ):
+    # fmt: on
+        print ( "This won't be formatted" )
+    print ( "This won't be formatted either" )
+else:
+    print ( "This will be formatted" )
+
+
+# Regression test for https://github.com/psf/black/issues/3184.
+class A:
+    async def call(param):
+        if param:
+            # fmt: off
+            if param[0:4] in (
+                "ABCD", "EFGH"
+            )  :
+                # fmt: on
+                print ( "This won't be formatted" )
+
+            elif param[0:4] in ("ZZZZ",):
+                print ( "This won't be formatted either" )
+
+        print ( "This will be formatted" )
+
+
+# Regression test for https://github.com/psf/black/issues/2985.
+class Named(t.Protocol):
+    # fmt: off
+    @property
+    def  this_wont_be_formatted ( self ) -> str: ...
+
+class Factory(t.Protocol):
+    def  this_will_be_formatted ( self, **kwargs ) -> Named: ...
+    # fmt: on
+
+
+# Regression test for https://github.com/psf/black/issues/3436.
+if x:
+    return x
+# fmt: off
+elif   unformatted:
+# fmt: on
+    will_be_formatted  ()
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -5,8 +5,7 @@
+         "console_scripts": [
+             "foo-bar"
+             "=foo.bar.:main",
+-        # fmt: on
+-            ]  # Includes an formatted indentation.
++        ],
+     },
+ )
+ 
+@@ -18,8 +17,8 @@
+         "ls",
+         "-la",
+     ]
+-    # fmt: on
+-    + path,
++    + # fmt: on
++    path,
+     check=True,
+ )
+ 
+@@ -27,9 +26,8 @@
+ # Regression test for https://github.com/psf/black/issues/3026.
+ def test_func():
+     # yapf: disable
+-    if  unformatted(  args  ):
++    if unformatted(args):
+         return True
+-    # yapf: enable
+     elif b:
+         return True
+ 
+@@ -39,10 +37,10 @@
+ # Regression test for https://github.com/psf/black/issues/2567.
+ if True:
+     # fmt: off
+-    for _ in range( 1 ):
+-    # fmt: on
+-        print ( "This won't be formatted" )
+-    print ( "This won't be formatted either" )
++    for _ in range(1):
++        # fmt: on
++        print("This won't be formatted")
++    print("This won't be formatted either")
+ else:
+     print("This will be formatted")
+ 
+@@ -52,14 +50,11 @@
+     async def call(param):
+         if param:
+             # fmt: off
+-            if param[0:4] in (
+-                "ABCD", "EFGH"
+-            )  :
++            if param[0:4] in ("ABCD", "EFGH"):
+                 # fmt: on
+-                print ( "This won't be formatted" )
+-
++                print("This won't be formatted")
+             elif param[0:4] in ("ZZZZ",):
+-                print ( "This won't be formatted either" )
++                print("This won't be formatted either")
+ 
+         print("This will be formatted")
+ 
+@@ -68,20 +63,21 @@
+ class Named(t.Protocol):
+     # fmt: off
+     @property
+-    def  this_wont_be_formatted ( self ) -> str: ...
++    def this_wont_be_formatted(self) -> str:
++        ...
+ 
+ 
+ class Factory(t.Protocol):
+     def this_will_be_formatted(self, **kwargs) -> Named:
+         ...
+ 
+-    # fmt: on
+ 
++# fmt: on
++
+ 
+ # Regression test for https://github.com/psf/black/issues/3436.
+ if x:
+     return x
+-# fmt: off
+-elif   unformatted:
++elif unformatted:
+     # fmt: on
+-    will_be_formatted()
+\ No newline at end of file
++    will_be_formatted()
+
+```
+
+## Ruff Output
+
+```py
+# Regression test for https://github.com/psf/black/issues/3129.
+setup(
+    entry_points={
+        # fmt: off
+        "console_scripts": [
+            "foo-bar"
+            "=foo.bar.:main",
+        ],
+    },
+)
+
+
+# Regression test for https://github.com/psf/black/issues/2015.
+run(
+    # fmt: off
+    [
+        "ls",
+        "-la",
+    ]
+    + # fmt: on
+    path,
+    check=True,
+)
+
+
+# Regression test for https://github.com/psf/black/issues/3026.
+def test_func():
+    # yapf: disable
+    if unformatted(args):
+        return True
+    elif b:
+        return True
+
+    return False
+
+
+# Regression test for https://github.com/psf/black/issues/2567.
+if True:
+    # fmt: off
+    for _ in range(1):
+        # fmt: on
+        print("This won't be formatted")
+    print("This won't be formatted either")
+else:
+    print("This will be formatted")
+
+
+# Regression test for https://github.com/psf/black/issues/3184.
+class A:
+    async def call(param):
+        if param:
+            # fmt: off
+            if param[0:4] in ("ABCD", "EFGH"):
+                # fmt: on
+                print("This won't be formatted")
+            elif param[0:4] in ("ZZZZ",):
+                print("This won't be formatted either")
+
+        print("This will be formatted")
+
+
+# Regression test for https://github.com/psf/black/issues/2985.
+class Named(t.Protocol):
+    # fmt: off
+    @property
+    def this_wont_be_formatted(self) -> str:
+        ...
+
+
+class Factory(t.Protocol):
+    def this_will_be_formatted(self, **kwargs) -> Named:
+        ...
+
+
+# fmt: on
+
+
+# Regression test for https://github.com/psf/black/issues/3436.
+if x:
+    return x
+elif unformatted:
+    # fmt: on
+    will_be_formatted()
+
+```
+
+## Black Output
+
+```py
+# Regression test for https://github.com/psf/black/issues/3129.
+setup(
+    entry_points={
+        # fmt: off
+        "console_scripts": [
+            "foo-bar"
+            "=foo.bar.:main",
+        # fmt: on
+            ]  # Includes an formatted indentation.
+    },
+)
+
+
+# Regression test for https://github.com/psf/black/issues/2015.
+run(
+    # fmt: off
+    [
+        "ls",
+        "-la",
+    ]
+    # fmt: on
+    + path,
+    check=True,
+)
+
+
+# Regression test for https://github.com/psf/black/issues/3026.
+def test_func():
+    # yapf: disable
+    if  unformatted(  args  ):
+        return True
+    # yapf: enable
+    elif b:
+        return True
+
+    return False
+
+
+# Regression test for https://github.com/psf/black/issues/2567.
+if True:
+    # fmt: off
+    for _ in range( 1 ):
+    # fmt: on
+        print ( "This won't be formatted" )
+    print ( "This won't be formatted either" )
+else:
+    print("This will be formatted")
+
+
+# Regression test for https://github.com/psf/black/issues/3184.
+class A:
+    async def call(param):
+        if param:
+            # fmt: off
+            if param[0:4] in (
+                "ABCD", "EFGH"
+            )  :
+                # fmt: on
+                print ( "This won't be formatted" )
+
+            elif param[0:4] in ("ZZZZ",):
+                print ( "This won't be formatted either" )
+
+        print("This will be formatted")
+
+
+# Regression test for https://github.com/psf/black/issues/2985.
+class Named(t.Protocol):
+    # fmt: off
+    @property
+    def  this_wont_be_formatted ( self ) -> str: ...
+
+
+class Factory(t.Protocol):
+    def this_will_be_formatted(self, **kwargs) -> Named:
+        ...
+
+    # fmt: on
+
+
+# Regression test for https://github.com/psf/black/issues/3436.
+if x:
+    return x
+# fmt: off
+elif   unformatted:
+    # fmt: on
+    will_be_formatted()
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtskip2_py.snap

@@ -0,0 +1,72 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip2.py
+---
+## Input
+
+```py
+l1 = ["This list should be broken up", "into multiple lines", "because it is way too long"]
+l2 = ["But this list shouldn't", "even though it also has", "way too many characters in it"]  # fmt: skip
+l3 = ["I have", "trailing comma", "so I should be braked",]
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -3,7 +3,11 @@
+     "into multiple lines",
+     "because it is way too long",
+ ]
+-l2 = ["But this list shouldn't", "even though it also has", "way too many characters in it"]  # fmt: skip
++l2 = [
++    "But this list shouldn't",
++    "even though it also has",
++    "way too many characters in it",
++]  # fmt: skip
+ l3 = [
+     "I have",
+     "trailing comma",
+
+```
+
+## Ruff Output
+
+```py
+l1 = [
+    "This list should be broken up",
+    "into multiple lines",
+    "because it is way too long",
+]
+l2 = [
+    "But this list shouldn't",
+    "even though it also has",
+    "way too many characters in it",
+]  # fmt: skip
+l3 = [
+    "I have",
+    "trailing comma",
+    "so I should be braked",
+]
+```
+
+## Black Output
+
+```py
+l1 = [
+    "This list should be broken up",
+    "into multiple lines",
+    "because it is way too long",
+]
+l2 = ["But this list shouldn't", "even though it also has", "way too many characters in it"]  # fmt: skip
+l3 = [
+    "I have",
+    "trailing comma",
+    "so I should be braked",
+]
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtskip3_py.snap

@@ -0,0 +1,67 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip3.py
+---
+## Input
+
+```py
+a  =    3
+# fmt: off
+b,    c = 1, 2
+d =    6  # fmt: skip
+e = 5
+# fmt: on
+f = ["This is a very long line that should be formatted into a clearer line ", "by rearranging."]
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,7 +1,7 @@
+ a = 3
+ # fmt: off
+-b,    c = 1, 2
+-d =    6  # fmt: skip
++b, c = 1, 2
++d = 6  # fmt: skip
+ e = 5
+ # fmt: on
+ f = [
+
+```
+
+## Ruff Output
+
+```py
+a = 3
+# fmt: off
+b, c = 1, 2
+d = 6  # fmt: skip
+e = 5
+# fmt: on
+f = [
+    "This is a very long line that should be formatted into a clearer line ",
+    "by rearranging.",
+]
+```
+
+## Black Output
+
+```py
+a = 3
+# fmt: off
+b,    c = 1, 2
+d =    6  # fmt: skip
+e = 5
+# fmt: on
+f = [
+    "This is a very long line that should be formatted into a clearer line ",
+    "by rearranging.",
+]
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtskip5_py.snap

@@ -0,0 +1,67 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip5.py
+---
+## Input
+
+```py
+a, b, c = 3, 4,       5
+if (
+    a ==    3
+    and b    != 9  # fmt: skip
+    and c is not None
+):
+    print("I'm good!")
+else:
+    print("I'm bad")
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,9 +1,5 @@
+ a, b, c = 3, 4, 5
+-if (
+-    a == 3
+-    and b    != 9  # fmt: skip
+-    and c is not None
+-):
++if a == 3 and b != 9 and c is not None:  # fmt: skip
+     print("I'm good!")
+ else:
+-    print("I'm bad")
+\ No newline at end of file
++    print("I'm bad")
+
+```
+
+## Ruff Output
+
+```py
+a, b, c = 3, 4, 5
+if a == 3 and b != 9 and c is not None:  # fmt: skip
+    print("I'm good!")
+else:
+    print("I'm bad")
+
+```
+
+## Black Output
+
+```py
+a, b, c = 3, 4, 5
+if (
+    a == 3
+    and b    != 9  # fmt: skip
+    and c is not None
+):
+    print("I'm good!")
+else:
+    print("I'm bad")
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtskip6_py.snap

@@ -0,0 +1,53 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip6.py
+---
+## Input
+
+```py
+class A:
+    def f(self):
+        for line in range(10):
+            if True:
+                pass  # fmt: skip
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -2,4 +2,4 @@
+     def f(self):
+         for line in range(10):
+             if True:
+-                pass  # fmt: skip
+\ No newline at end of file
++                pass
+
+```
+
+## Ruff Output
+
+```py
+class A:
+    def f(self):
+        for line in range(10):
+            if True:
+                pass
+
+```
+
+## Black Output
+
+```py
+class A:
+    def f(self):
+        for line in range(10):
+            if True:
+                pass  # fmt: skip
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtskip7_py.snap

@@ -0,0 +1,52 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip7.py
+---
+## Input
+
+```py
+a =     "this is some code"
+b =     5  #fmt:skip
+c = 9  #fmt: skip
+d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  #fmt:skip
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,4 +1,4 @@
+ a = "this is some code"
+-b =     5  # fmt:skip
+-c = 9  # fmt: skip
+-d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  # fmt:skip
+\ No newline at end of file
++b = 5  #fmt:skip
++c = 9  #fmt: skip
++d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  #fmt:skip
+\ No newline at end of file
+
+```
+
+## Ruff Output
+
+```py
+a = "this is some code"
+b = 5  #fmt:skip
+c = 9  #fmt: skip
+d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  #fmt:skip
+```
+
+## Black Output
+
+```py
+a = "this is some code"
+b =     5  # fmt:skip
+c = 9  # fmt: skip
+d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  # fmt:skip
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fmtskip_py.snap

@@ -0,0 +1,45 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fmtskip.py
+---
+## Input
+
+```py
+a, b = 1, 2
+c =    6  # fmt: skip
+d = 5
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,3 +1,3 @@
+ a, b = 1, 2
+-c =    6  # fmt: skip
++c = 6  # fmt: skip
+ d = 5
+\ No newline at end of file
+
+```
+
+## Ruff Output
+
+```py
+a, b = 1, 2
+c = 6  # fmt: skip
+d = 5
+```
+
+## Black Output
+
+```py
+a, b = 1, 2
+c =    6  # fmt: skip
+d = 5
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__fstring_py.snap

@@ -0,0 +1,65 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/fstring.py
+---
+## Input
+
+```py
+f"f-string without formatted values is just a string"
+f"{{NOT a formatted value}}"
+f"{{NOT 'a' \"formatted\" \"value\"}}"
+f"some f-string with {a} {few():.2f} {formatted.values!r}"
+f'some f-string with {a} {few(""):.2f} {formatted.values!r}'
+f"{f'''{'nested'} inner'''} outer"
+f"\"{f'{nested} inner'}\" outer"
+f"space between opening braces: { {a for a in (1, 2, 3)}}"
+f'Hello \'{tricky + "example"}\''
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -1,6 +1,6 @@
+ f"f-string without formatted values is just a string"
+ f"{{NOT a formatted value}}"
+-f'{{NOT \'a\' "formatted" "value"}}'
++f"{{NOT 'a' \"formatted\" \"value\"}}"
+ f"some f-string with {a} {few():.2f} {formatted.values!r}"
+ f'some f-string with {a} {few(""):.2f} {formatted.values!r}'
+ f"{f'''{'nested'} inner'''} outer"
+
+```
+
+## Ruff Output
+
+```py
+f"f-string without formatted values is just a string"
+f"{{NOT a formatted value}}"
+f"{{NOT 'a' \"formatted\" \"value\"}}"
+f"some f-string with {a} {few():.2f} {formatted.values!r}"
+f'some f-string with {a} {few(""):.2f} {formatted.values!r}'
+f"{f'''{'nested'} inner'''} outer"
+f"\"{f'{nested} inner'}\" outer"
+f"space between opening braces: { {a for a in (1, 2, 3)}}"
+f'Hello \'{tricky + "example"}\''
+```
+
+## Black Output
+
+```py
+f"f-string without formatted values is just a string"
+f"{{NOT a formatted value}}"
+f'{{NOT \'a\' "formatted" "value"}}'
+f"some f-string with {a} {few():.2f} {formatted.values!r}"
+f'some f-string with {a} {few(""):.2f} {formatted.values!r}'
+f"{f'''{'nested'} inner'''} outer"
+f"\"{f'{nested} inner'}\" outer"
+f"space between opening braces: { {a for a in (1, 2, 3)}}"
+f'Hello \'{tricky + "example"}\''
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__function2_py.snap

@@ -0,0 +1,223 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/function2.py
+---
+## Input
+
+```py
+def f(
+  a,
+  **kwargs,
+) -> A:
+    with cache_dir():
+        if something:
+            result = (
+                CliRunner().invoke(black.main, [str(src1), str(src2), "--diff", "--check"])
+            )
+    limited.append(-limited.pop())  # negate top
+    return A(
+        very_long_argument_name1=very_long_value_for_the_argument,
+        very_long_argument_name2=-very.long.value.for_the_argument,
+        **kwargs,
+    )
+def g():
+    "Docstring."
+    def inner():
+        pass
+    print("Inner defs should breathe a little.")
+def h():
+    def inner():
+        pass
+    print("Inner defs should breathe a little.")
+
+
+if os.name == "posix":
+    import termios
+    def i_should_be_followed_by_only_one_newline():
+        pass
+elif os.name == "nt":
+    try:
+        import msvcrt
+        def i_should_be_followed_by_only_one_newline():
+            pass
+
+    except ImportError:
+
+        def i_should_be_followed_by_only_one_newline():
+            pass
+
+elif False:
+
+    class IHopeYouAreHavingALovelyDay:
+        def __call__(self):
+            print("i_should_be_followed_by_only_one_newline")
+else:
+
+    def foo():
+        pass
+
+with hmm_but_this_should_get_two_preceding_newlines():
+    pass
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -63,4 +63,4 @@
+ 
+ 
+ with hmm_but_this_should_get_two_preceding_newlines():
+-    pass
+\ No newline at end of file
++    pass
+
+```
+
+## Ruff Output
+
+```py
+def f(
+    a,
+    **kwargs,
+) -> A:
+    with cache_dir():
+        if something:
+            result = CliRunner().invoke(
+                black.main,
+                [str(src1), str(src2), "--diff", "--check"],
+            )
+    limited.append(-limited.pop())  # negate top
+    return A(
+        very_long_argument_name1=very_long_value_for_the_argument,
+        very_long_argument_name2=-very.long.value.for_the_argument,
+        **kwargs,
+    )
+
+
+def g():
+    "Docstring."
+
+    def inner():
+        pass
+
+    print("Inner defs should breathe a little.")
+
+
+def h():
+    def inner():
+        pass
+
+    print("Inner defs should breathe a little.")
+
+
+if os.name == "posix":
+    import termios
+
+    def i_should_be_followed_by_only_one_newline():
+        pass
+
+elif os.name == "nt":
+    try:
+        import msvcrt
+
+        def i_should_be_followed_by_only_one_newline():
+            pass
+
+    except ImportError:
+
+        def i_should_be_followed_by_only_one_newline():
+            pass
+
+elif False:
+
+    class IHopeYouAreHavingALovelyDay:
+        def __call__(self):
+            print("i_should_be_followed_by_only_one_newline")
+
+else:
+
+    def foo():
+        pass
+
+
+with hmm_but_this_should_get_two_preceding_newlines():
+    pass
+
+```
+
+## Black Output
+
+```py
+def f(
+    a,
+    **kwargs,
+) -> A:
+    with cache_dir():
+        if something:
+            result = CliRunner().invoke(
+                black.main,
+                [str(src1), str(src2), "--diff", "--check"],
+            )
+    limited.append(-limited.pop())  # negate top
+    return A(
+        very_long_argument_name1=very_long_value_for_the_argument,
+        very_long_argument_name2=-very.long.value.for_the_argument,
+        **kwargs,
+    )
+
+
+def g():
+    "Docstring."
+
+    def inner():
+        pass
+
+    print("Inner defs should breathe a little.")
+
+
+def h():
+    def inner():
+        pass
+
+    print("Inner defs should breathe a little.")
+
+
+if os.name == "posix":
+    import termios
+
+    def i_should_be_followed_by_only_one_newline():
+        pass
+
+elif os.name == "nt":
+    try:
+        import msvcrt
+
+        def i_should_be_followed_by_only_one_newline():
+            pass
+
+    except ImportError:
+
+        def i_should_be_followed_by_only_one_newline():
+            pass
+
+elif False:
+
+    class IHopeYouAreHavingALovelyDay:
+        def __call__(self):
+            print("i_should_be_followed_by_only_one_newline")
+
+else:
+
+    def foo():
+        pass
+
+
+with hmm_but_this_should_get_two_preceding_newlines():
+    pass
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__function_py.snap

@@ -0,0 +1,493 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/function.py
+---
+## Input
+
+```py
+#!/usr/bin/env python3
+import asyncio
+import sys
+
+from third_party import X, Y, Z
+
+from library import some_connection, \
+                    some_decorator
+f'trigger 3.6 mode'
+def func_no_args():
+  a; b; c
+  if True: raise RuntimeError
+  if False: ...
+  for i in range(10):
+    print(i)
+    continue
+  exec("new-style exec", {}, {})
+  return None
+async def coroutine(arg, exec=False):
+ "Single-line docstring. Multiline is harder to reformat."
+ async with some_connection() as conn:
+     await conn.do_what_i_mean('SELECT bobby, tables FROM xkcd', timeout=2)
+ await asyncio.sleep(1)
+@asyncio.coroutine
+@some_decorator(
+with_args=True,
+many_args=[1,2,3]
+)
+def function_signature_stress_test(number:int,no_annotation=None,text:str="default",* ,debug:bool=False,**kwargs) -> str:
+ return text[number:-1]
+def spaces(a=1, b=(), c=[], d={}, e=True, f=-1, g=1 if False else 2, h="", i=r''):
+ offset = attr.ib(default=attr.Factory( lambda: _r.uniform(10000, 200000)))
+ assert task._cancel_stack[:len(old_stack)] == old_stack
+def spaces_types(a: int = 1, b: tuple = (), c: list = [], d: dict = {}, e: bool = True, f: int = -1, g: int = 1 if False else 2, h: str = "", i: str = r''): ...
+def spaces2(result= _core.Value(None)):
+ assert fut is self._read_fut, (fut, self._read_fut)
+    
+def example(session):
+    result = session.query(models.Customer.id).filter(
+        models.Customer.account_id == account_id,
+        models.Customer.email == email_address,
+    ).order_by(
+        models.Customer.id.asc()
+    ).all()
+def long_lines():
+    if True:
+        typedargslist.extend(
+            gen_annotated_params(ast_args.kwonlyargs, ast_args.kw_defaults, parameters, implicit_default=True)
+        )
+        typedargslist.extend(
+            gen_annotated_params(
+                ast_args.kwonlyargs, ast_args.kw_defaults, parameters, implicit_default=True,
+                # trailing standalone comment
+            )
+        )
+    _type_comment_re = re.compile(
+        r"""
+        ^
+        [\t ]*
+        \#[ ]type:[ ]*
+        (?P<type>
+            [^#\t\n]+?
+        )
+        (?<!ignore)     # note: this will force the non-greedy + in <type> to match
+                        # a trailing space which is why we need the silliness below
+        (?<!ignore[ ]{1})(?<!ignore[ ]{2})(?<!ignore[ ]{3})(?<!ignore[ ]{4})
+        (?<!ignore[ ]{5})(?<!ignore[ ]{6})(?<!ignore[ ]{7})(?<!ignore[ ]{8})
+        (?<!ignore[ ]{9})(?<!ignore[ ]{10})
+        [\t ]*
+        (?P<nl>
+            (?:\#[^\n]*)?
+            \n?
+        )
+        $
+        """, re.MULTILINE | re.VERBOSE
+    )
+def trailing_comma():
+    mapping = {
+    A: 0.25 * (10.0 / 12),
+    B: 0.1 * (10.0 / 12),
+    C: 0.1 * (10.0 / 12),
+    D: 0.1 * (10.0 / 12),
+}
+def f(
+  a,
+  **kwargs,
+) -> A:
+    return (
+        yield from A(
+            very_long_argument_name1=very_long_value_for_the_argument,
+            very_long_argument_name2=very_long_value_for_the_argument,
+            **kwargs,
+        )
+    )
+def __await__(): return (yield)
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -6,7 +6,7 @@
+ 
+ from library import some_connection, some_decorator
+ 
+-f"trigger 3.6 mode"
++f'trigger 3.6 mode'
+ 
+ 
+ def func_no_args():
+@@ -27,7 +27,7 @@
+ async def coroutine(arg, exec=False):
+     "Single-line docstring. Multiline is harder to reformat."
+     async with some_connection() as conn:
+-        await conn.do_what_i_mean("SELECT bobby, tables FROM xkcd", timeout=2)
++        await conn.do_what_i_mean('SELECT bobby, tables FROM xkcd', timeout=2)
+     await asyncio.sleep(1)
+ 
+ 
+@@ -44,7 +44,7 @@
+     return text[number:-1]
+ 
+ 
+-def spaces(a=1, b=(), c=[], d={}, e=True, f=-1, g=1 if False else 2, h="", i=r""):
++def spaces(a=1, b=(), c=[], d={}, e=True, f=-1, g=1 if False else 2, h="", i=r''):
+     offset = attr.ib(default=attr.Factory(lambda: _r.uniform(10000, 200000)))
+     assert task._cancel_stack[: len(old_stack)] == old_stack
+ 
+@@ -58,25 +58,20 @@
+     f: int = -1,
+     g: int = 1 if False else 2,
+     h: str = "",
+-    i: str = r"",
++    i: str = r'',
+ ):
+     ...
+ 
+ 
+ def spaces2(result=_core.Value(None)):
+-    assert fut is self._read_fut, (fut, self._read_fut)
++    assert fut is self._read_fut, fut, self._read_fut
+ 
+ 
+ def example(session):
+-    result = (
+-        session.query(models.Customer.id)
+-        .filter(
+-            models.Customer.account_id == account_id,
+-            models.Customer.email == email_address,
+-        )
+-        .order_by(models.Customer.id.asc())
+-        .all()
+-    )
++    result = session.query(models.Customer.id).filter(
++        models.Customer.account_id == account_id,
++        models.Customer.email == email_address,
++    ).order_by(models.Customer.id.asc()).all()
+ 
+ 
+ def long_lines():
+@@ -135,14 +130,13 @@
+     a,
+     **kwargs,
+ ) -> A:
+-    return (
++    return
+         yield from A(
+             very_long_argument_name1=very_long_value_for_the_argument,
+             very_long_argument_name2=very_long_value_for_the_argument,
+             **kwargs,
+         )
+-    )
+ 
+ 
+ def __await__():
+-    return (yield)
+\ No newline at end of file
++    return yield
+
+```
+
+## Ruff Output
+
+```py
+#!/usr/bin/env python3
+import asyncio
+import sys
+
+from third_party import X, Y, Z
+
+from library import some_connection, some_decorator
+
+f'trigger 3.6 mode'
+
+
+def func_no_args():
+    a
+    b
+    c
+    if True:
+        raise RuntimeError
+    if False:
+        ...
+    for i in range(10):
+        print(i)
+        continue
+    exec("new-style exec", {}, {})
+    return None
+
+
+async def coroutine(arg, exec=False):
+    "Single-line docstring. Multiline is harder to reformat."
+    async with some_connection() as conn:
+        await conn.do_what_i_mean('SELECT bobby, tables FROM xkcd', timeout=2)
+    await asyncio.sleep(1)
+
+
+@asyncio.coroutine
+@some_decorator(with_args=True, many_args=[1, 2, 3])
+def function_signature_stress_test(
+    number: int,
+    no_annotation=None,
+    text: str = "default",
+    *,
+    debug: bool = False,
+    **kwargs,
+) -> str:
+    return text[number:-1]
+
+
+def spaces(a=1, b=(), c=[], d={}, e=True, f=-1, g=1 if False else 2, h="", i=r''):
+    offset = attr.ib(default=attr.Factory(lambda: _r.uniform(10000, 200000)))
+    assert task._cancel_stack[: len(old_stack)] == old_stack
+
+
+def spaces_types(
+    a: int = 1,
+    b: tuple = (),
+    c: list = [],
+    d: dict = {},
+    e: bool = True,
+    f: int = -1,
+    g: int = 1 if False else 2,
+    h: str = "",
+    i: str = r'',
+):
+    ...
+
+
+def spaces2(result=_core.Value(None)):
+    assert fut is self._read_fut, fut, self._read_fut
+
+
+def example(session):
+    result = session.query(models.Customer.id).filter(
+        models.Customer.account_id == account_id,
+        models.Customer.email == email_address,
+    ).order_by(models.Customer.id.asc()).all()
+
+
+def long_lines():
+    if True:
+        typedargslist.extend(
+            gen_annotated_params(
+                ast_args.kwonlyargs,
+                ast_args.kw_defaults,
+                parameters,
+                implicit_default=True,
+            )
+        )
+        typedargslist.extend(
+            gen_annotated_params(
+                ast_args.kwonlyargs,
+                ast_args.kw_defaults,
+                parameters,
+                implicit_default=True,
+                # trailing standalone comment
+            )
+        )
+    _type_comment_re = re.compile(
+        r"""
+        ^
+        [\t ]*
+        \#[ ]type:[ ]*
+        (?P<type>
+            [^#\t\n]+?
+        )
+        (?<!ignore)     # note: this will force the non-greedy + in <type> to match
+                        # a trailing space which is why we need the silliness below
+        (?<!ignore[ ]{1})(?<!ignore[ ]{2})(?<!ignore[ ]{3})(?<!ignore[ ]{4})
+        (?<!ignore[ ]{5})(?<!ignore[ ]{6})(?<!ignore[ ]{7})(?<!ignore[ ]{8})
+        (?<!ignore[ ]{9})(?<!ignore[ ]{10})
+        [\t ]*
+        (?P<nl>
+            (?:\#[^\n]*)?
+            \n?
+        )
+        $
+        """,
+        re.MULTILINE | re.VERBOSE,
+    )
+
+
+def trailing_comma():
+    mapping = {
+        A: 0.25 * (10.0 / 12),
+        B: 0.1 * (10.0 / 12),
+        C: 0.1 * (10.0 / 12),
+        D: 0.1 * (10.0 / 12),
+    }
+
+
+def f(
+    a,
+    **kwargs,
+) -> A:
+    return
+        yield from A(
+            very_long_argument_name1=very_long_value_for_the_argument,
+            very_long_argument_name2=very_long_value_for_the_argument,
+            **kwargs,
+        )
+
+
+def __await__():
+    return yield
+
+```
+
+## Black Output
+
+```py
+#!/usr/bin/env python3
+import asyncio
+import sys
+
+from third_party import X, Y, Z
+
+from library import some_connection, some_decorator
+
+f"trigger 3.6 mode"
+
+
+def func_no_args():
+    a
+    b
+    c
+    if True:
+        raise RuntimeError
+    if False:
+        ...
+    for i in range(10):
+        print(i)
+        continue
+    exec("new-style exec", {}, {})
+    return None
+
+
+async def coroutine(arg, exec=False):
+    "Single-line docstring. Multiline is harder to reformat."
+    async with some_connection() as conn:
+        await conn.do_what_i_mean("SELECT bobby, tables FROM xkcd", timeout=2)
+    await asyncio.sleep(1)
+
+
+@asyncio.coroutine
+@some_decorator(with_args=True, many_args=[1, 2, 3])
+def function_signature_stress_test(
+    number: int,
+    no_annotation=None,
+    text: str = "default",
+    *,
+    debug: bool = False,
+    **kwargs,
+) -> str:
+    return text[number:-1]
+
+
+def spaces(a=1, b=(), c=[], d={}, e=True, f=-1, g=1 if False else 2, h="", i=r""):
+    offset = attr.ib(default=attr.Factory(lambda: _r.uniform(10000, 200000)))
+    assert task._cancel_stack[: len(old_stack)] == old_stack
+
+
+def spaces_types(
+    a: int = 1,
+    b: tuple = (),
+    c: list = [],
+    d: dict = {},
+    e: bool = True,
+    f: int = -1,
+    g: int = 1 if False else 2,
+    h: str = "",
+    i: str = r"",
+):
+    ...
+
+
+def spaces2(result=_core.Value(None)):
+    assert fut is self._read_fut, (fut, self._read_fut)
+
+
+def example(session):
+    result = (
+        session.query(models.Customer.id)
+        .filter(
+            models.Customer.account_id == account_id,
+            models.Customer.email == email_address,
+        )
+        .order_by(models.Customer.id.asc())
+        .all()
+    )
+
+
+def long_lines():
+    if True:
+        typedargslist.extend(
+            gen_annotated_params(
+                ast_args.kwonlyargs,
+                ast_args.kw_defaults,
+                parameters,
+                implicit_default=True,
+            )
+        )
+        typedargslist.extend(
+            gen_annotated_params(
+                ast_args.kwonlyargs,
+                ast_args.kw_defaults,
+                parameters,
+                implicit_default=True,
+                # trailing standalone comment
+            )
+        )
+    _type_comment_re = re.compile(
+        r"""
+        ^
+        [\t ]*
+        \#[ ]type:[ ]*
+        (?P<type>
+            [^#\t\n]+?
+        )
+        (?<!ignore)     # note: this will force the non-greedy + in <type> to match
+                        # a trailing space which is why we need the silliness below
+        (?<!ignore[ ]{1})(?<!ignore[ ]{2})(?<!ignore[ ]{3})(?<!ignore[ ]{4})
+        (?<!ignore[ ]{5})(?<!ignore[ ]{6})(?<!ignore[ ]{7})(?<!ignore[ ]{8})
+        (?<!ignore[ ]{9})(?<!ignore[ ]{10})
+        [\t ]*
+        (?P<nl>
+            (?:\#[^\n]*)?
+            \n?
+        )
+        $
+        """,
+        re.MULTILINE | re.VERBOSE,
+    )
+
+
+def trailing_comma():
+    mapping = {
+        A: 0.25 * (10.0 / 12),
+        B: 0.1 * (10.0 / 12),
+        C: 0.1 * (10.0 / 12),
+        D: 0.1 * (10.0 / 12),
+    }
+
+
+def f(
+    a,
+    **kwargs,
+) -> A:
+    return (
+        yield from A(
+            very_long_argument_name1=very_long_value_for_the_argument,
+            very_long_argument_name2=very_long_value_for_the_argument,
+            **kwargs,
+        )
+    )
+
+
+def __await__():
+    return (yield)
+```
+
+

crates/ruff_python_formatter/src/snapshots/ruff_python_formatter__tests__black_test__function_trailing_comma_py.snap

@@ -0,0 +1,419 @@
+---
+source: crates/ruff_python_formatter/src/lib.rs
+expression: snapshot
+input_file: crates/ruff_python_formatter/resources/test/fixtures/black/simple_cases/function_trailing_comma.py
+---
+## Input
+
+```py
+def f(a,):
+    d = {'key': 'value',}
+    tup = (1,)
+
+def f2(a,b,):
+    d = {'key': 'value', 'key2': 'value2',}
+    tup = (1,2,)
+
+def f(a:int=1,):
+    call(arg={'explode': 'this',})
+    call2(arg=[1,2,3],)
+    x = {
+        "a": 1,
+        "b": 2,
+    }["a"]
+    if a == {"a": 1,"b": 2,"c": 3,"d": 4,"e": 5,"f": 6,"g": 7,"h": 8,}["a"]:
+        pass
+
+def xxxxxxxxxxxxxxxxxxxxxxxxxxxx() -> Set[
+    "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+]:
+    json = {"k": {"k2": {"k3": [1,]}}}
+
+
+
+# The type annotation shouldn't get a trailing comma since that would change its type.
+# Relevant bug report: https://github.com/psf/black/issues/2381.
+def some_function_with_a_really_long_name() -> (
+    returning_a_deeply_nested_import_of_a_type_i_suppose
+):
+    pass
+
+
+def some_method_with_a_really_long_name(very_long_parameter_so_yeah: str, another_long_parameter: int) -> (
+    another_case_of_returning_a_deeply_nested_import_of_a_type_i_suppose_cause_why_not
+):
+    pass
+
+
+def func() -> (
+    also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(this_shouldn_t_get_a_trailing_comma_too)
+):
+    pass
+
+
+def func() -> ((also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
+        this_shouldn_t_get_a_trailing_comma_too
+    ))
+):
+    pass
+
+
+# Make sure inner one-element tuple won't explode
+some_module.some_function(
+    argument1, (one_element_tuple,), argument4, argument5, argument6
+)
+
+# Inner trailing comma causes outer to explode
+some_module.some_function(
+    argument1, (one, two,), argument4, argument5, argument6
+)
+
+```
+
+## Black Differences
+
+```diff
+--- Black
++++ Ruff
+@@ -2,7 +2,7 @@
+     a,
+ ):
+     d = {
+-        "key": "value",
++        'key': 'value',
+     }
+     tup = (1,)
+ 
+@@ -12,8 +12,8 @@
+     b,
+ ):
+     d = {
+-        "key": "value",
+-        "key2": "value2",
++        'key': 'value',
++        'key2': 'value2',
+     }
+     tup = (
+         1,
+@@ -26,7 +26,7 @@
+ ):
+     call(
+         arg={
+-            "explode": "this",
++            'explode': 'this',
+         }
+     )
+     call2(
+@@ -52,53 +52,52 @@
+         pass
+ 
+ 
+-def xxxxxxxxxxxxxxxxxxxxxxxxxxxx() -> (
+-    Set["xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"]
+-):
++def xxxxxxxxxxxxxxxxxxxxxxxxxxxx() -> Set[
++    "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
++]:
+     json = {
+         "k": {
+             "k2": {
+                 "k3": [
+                     1,
+-                ]
+-            }
+-        }
++                ],
++            },
++        },
+     }
+ 
+ 
+ # The type annotation shouldn't get a trailing comma since that would change its type.
+ # Relevant bug report: https://github.com/psf/black/issues/2381.
+-def some_function_with_a_really_long_name() -> (
+-    returning_a_deeply_nested_import_of_a_type_i_suppose
+-):
++def some_function_with_a_really_long_name() -> returning_a_deeply_nested_import_of_a_type_i_suppose:
+     pass
+ 
+ 
+ def some_method_with_a_really_long_name(
+-    very_long_parameter_so_yeah: str, another_long_parameter: int
++    very_long_parameter_so_yeah: str,
++    another_long_parameter: int,
+ ) -> another_case_of_returning_a_deeply_nested_import_of_a_type_i_suppose_cause_why_not:
+     pass
+ 
+ 
+-def func() -> (
+-    also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
+-        this_shouldn_t_get_a_trailing_comma_too
+-    )
++def func() -> also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
++    this_shouldn_t_get_a_trailing_comma_too
+ ):
+     pass
+ 
+ 
+-def func() -> (
+-    also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
+-        this_shouldn_t_get_a_trailing_comma_too
+-    )
++def func() -> also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
++    this_shouldn_t_get_a_trailing_comma_too
+ ):
+     pass
+ 
+ 
+ # Make sure inner one-element tuple won't explode
+ some_module.some_function(
+-    argument1, (one_element_tuple,), argument4, argument5, argument6
++    argument1,
++    (one_element_tuple,),
++    argument4,
++    argument5,
++    argument6,
+ )
+ 
+ # Inner trailing comma causes outer to explode
+
+```
+
+## Ruff Output
+
+```py
+def f(
+    a,
+):
+    d = {
+        'key': 'value',
+    }
+    tup = (1,)
+
+
+def f2(
+    a,
+    b,
+):
+    d = {
+        'key': 'value',
+        'key2': 'value2',
+    }
+    tup = (
+        1,
+        2,
+    )
+
+
+def f(
+    a: int = 1,
+):
+    call(
+        arg={
+            'explode': 'this',
+        }
+    )
+    call2(
+        arg=[1, 2, 3],
+    )
+    x = {
+        "a": 1,
+        "b": 2,
+    }["a"]
+    if (
+        a
+        == {
+            "a": 1,
+            "b": 2,
+            "c": 3,
+            "d": 4,
+            "e": 5,
+            "f": 6,
+            "g": 7,
+            "h": 8,
+        }["a"]
+    ):
+        pass
+
+
+def xxxxxxxxxxxxxxxxxxxxxxxxxxxx() -> Set[
+    "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+]:
+    json = {
+        "k": {
+            "k2": {
+                "k3": [
+                    1,
+                ],
+            },
+        },
+    }
+
+
+# The type annotation shouldn't get a trailing comma since that would change its type.
+# Relevant bug report: https://github.com/psf/black/issues/2381.
+def some_function_with_a_really_long_name() -> returning_a_deeply_nested_import_of_a_type_i_suppose:
+    pass
+
+
+def some_method_with_a_really_long_name(
+    very_long_parameter_so_yeah: str,
+    another_long_parameter: int,
+) -> another_case_of_returning_a_deeply_nested_import_of_a_type_i_suppose_cause_why_not:
+    pass
+
+
+def func() -> also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
+    this_shouldn_t_get_a_trailing_comma_too
+):
+    pass
+
+
+def func() -> also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
+    this_shouldn_t_get_a_trailing_comma_too
+):
+    pass
+
+
+# Make sure inner one-element tuple won't explode
+some_module.some_function(
+    argument1,
+    (one_element_tuple,),
+    argument4,
+    argument5,
+    argument6,
+)
+
+# Inner trailing comma causes outer to explode
+some_module.some_function(
+    argument1,
+    (
+        one,
+        two,
+    ),
+    argument4,
+    argument5,
+    argument6,
+)
+```
+
+## Black Output
+
+```py
+def f(
+    a,
+):
+    d = {
+        "key": "value",
+    }
+    tup = (1,)
+
+
+def f2(
+    a,
+    b,
+):
+    d = {
+        "key": "value",
+        "key2": "value2",
+    }
+    tup = (
+        1,
+        2,
+    )
+
+
+def f(
+    a: int = 1,
+):
+    call(
+        arg={
+            "explode": "this",
+        }
+    )
+    call2(
+        arg=[1, 2, 3],
+    )
+    x = {
+        "a": 1,
+        "b": 2,
+    }["a"]
+    if (
+        a
+        == {
+            "a": 1,
+            "b": 2,
+            "c": 3,
+            "d": 4,
+            "e": 5,
+            "f": 6,
+            "g": 7,
+            "h": 8,
+        }["a"]
+    ):
+        pass
+
+
+def xxxxxxxxxxxxxxxxxxxxxxxxxxxx() -> (
+    Set["xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"]
+):
+    json = {
+        "k": {
+            "k2": {
+                "k3": [
+                    1,
+                ]
+            }
+        }
+    }
+
+
+# The type annotation shouldn't get a trailing comma since that would change its type.
+# Relevant bug report: https://github.com/psf/black/issues/2381.
+def some_function_with_a_really_long_name() -> (
+    returning_a_deeply_nested_import_of_a_type_i_suppose
+):
+    pass
+
+
+def some_method_with_a_really_long_name(
+    very_long_parameter_so_yeah: str, another_long_parameter: int
+) -> another_case_of_returning_a_deeply_nested_import_of_a_type_i_suppose_cause_why_not:
+    pass
+
+
+def func() -> (
+    also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
+        this_shouldn_t_get_a_trailing_comma_too
+    )
+):
+    pass
+
+
+def func() -> (
+    also_super_long_type_annotation_that_may_cause_an_AST_related_crash_in_black(
+        this_shouldn_t_get_a_trailing_comma_too
+    )
+):
+    pass
+
+
+# Make sure inner one-element tuple won't explode
+some_module.some_function(
+    argument1, (one_element_tuple,), argument4, argument5, argument6
+)
+
+# Inner trailing comma causes outer to explode
+some_module.some_function(
+    argument1,
+    (
+        one,
+        two,
+    ),
+    argument4,
+    argument5,
+    argument6,
+)
+```
+
+