Summary
--
This PR implements detecting the use of `await` expressions outside of
async functions. This is a reimplementation of
[await-outside-async
(PLE1142)](https://docs.astral.sh/ruff/rules/await-outside-async/) as a
semantic syntax error.
Despite the rule name, PLE1142 also applies to `async for` and `async
with`, so these are covered here too.
Test Plan
--
Existing PLE1142 tests.
I also deleted more code from the `SemanticSyntaxCheckerVisitor` to
avoid changes in other parser tests.
Summary
--
This PR reimplements [yield-outside-function
(F704)](https://docs.astral.sh/ruff/rules/yield-outside-function/) as a
semantic syntax error. Despite the name, this rule covers `yield from`
and `await` in addition to `yield`.
Test Plan
--
New linter tests, along with the existing F704 test.
---------
Co-authored-by: Dhruv Manilawala <dhruvmanila@gmail.com>
## Summary
Based on the discussion in
https://github.com/astral-sh/ruff/pull/17298#discussion_r2033975460, we
decided to move the scope handling out of the `SemanticSyntaxChecker`
and into the `SemanticSyntaxContext` trait. This PR implements that
refactor by:
- Reverting all of the `Checkpoint` and `in_async_context` code in the
`SemanticSyntaxChecker`
- Adding four new methods to the `SemanticSyntaxContext` trait
- `in_async_context`: matches `SemanticModel::in_async_context` and only
detects the nearest enclosing function
- `in_sync_comprehension`: uses the new `is_async` tracking on
`Generator` scopes to detect any enclosing sync comprehension
- `in_module_scope`: reports whether we're at the top-level scope
- `in_notebook`: reports whether we're in a Jupyter notebook
- In-lining the `TestContext` directly into the
`SemanticSyntaxCheckerVisitor`
- This allows modifying the context as the visitor traverses the AST,
which wasn't possible before
One potential question here is "why not add a single method returning a
`Scope` or `Scopes` to the context?" The main reason is that the `Scope`
type is defined in the `ruff_python_semantic` crate, which is not
currently a dependency of the parser. It also doesn't appear to be used
in red-knot. So it seemed best to use these more granular methods
instead of trying to access `Scope` in `ruff_python_parser` (and
red-knot).
## Test Plan
Existing parser and linter tests.
Summary
--
Detect async comprehensions nested in sync comprehensions in async
functions before Python 3.11, when this was [changed].
The actual logic of this rule is very straightforward, but properly
tracking the async scopes took a bit of work. An alternative to the
current approach is to offload the `in_async_context` check into the
`SemanticSyntaxContext` trait, but that actually required much more
extensive changes to the `TestContext` and also to ruff's semantic
model, as you can see in the changes up to
31554b473507034735bd410760fde6341d54a050. This version has the benefit
of mostly centralizing the state tracking in `SemanticSyntaxChecker`,
although there was some subtlety around deferred function body traversal
that made the changes to `Checker` more intrusive too (hence the new
linter test).
The `Checkpoint` struct/system is obviously overkill for now since it's
only tracking a single `bool`, but I thought it might be more useful
later.
[changed]: https://github.com/python/cpython/issues/77527
Test Plan
--
New inline tests and a new linter integration test.
Summary
--
This PR extends the checks in #17101 and #17282 to annotated assignments
after Python 3.13.
Currently stacked on #17282 to include `await`.
Test Plan
--
New inline tests. These are simpler than the other cases because there's
no place to put generics.
Summary
--
This PR extends the changes in #17101 to include `await` in the same
positions.
I also renamed the `valid_annotation_function` test to include `_py313`
and explicitly passed a Python version to contrast it with the `_py314`
version.
Test Plan
--
New test cases added to existing files.
Summary
--
This PR fixes the issue pointed out by @JelleZijlstra in
https://github.com/astral-sh/ruff/pull/17101#issuecomment-2777480204.
Namely, I conflated two very different errors from CPython:
```pycon
>>> def m[T](x: (yield from 1)): ...
File "<python-input-310>", line 1
def m[T](x: (yield from 1)): ...
^^^^^^^^^^^^
SyntaxError: yield expression cannot be used within the definition of a generic
>>> def m(x: (yield from 1)): ...
File "<python-input-311>", line 1
def m(x: (yield from 1)): ...
^^^^^^^^^^^^
SyntaxError: 'yield from' outside function
>>> def outer():
... def m(x: (yield from 1)): ...
...
>>>
```
I thought the second error was the same as the first, but `yield` (and
`yield from`) is actually valid in this position when inside a function
scope. The same is true for base classes, as pointed out in the original
comment.
We don't currently raise an error for `yield` outside of a function, but
that should be handled separately.
On the upside, this had the benefit of removing the
`InvalidExpressionPosition::BaseClass` variant and the
`allow_named_expr` field from the visitor because they were both no
longer used.
Test Plan
--
Updated inline tests.
Summary
--
This PR detects the use of invalid syntax in annotation scopes,
including
`yield` and `yield from` expressions and named expressions. I combined a
few
different types of CPython errors here, but I think the resulting error
messages
still make sense and are even preferable to what CPython gives. For
example, we
report `yield expression cannot be used in a type annotation` for both
of these:
```pycon
>>> def f[T](x: (yield 1)): ...
File "<python-input-26>", line 1
def f[T](x: (yield 1)): ...
^^^^^^^
SyntaxError: yield expression cannot be used within the definition of a generic
>>> def foo() -> (yield x): ...
File "<python-input-28>", line 1
def foo() -> (yield x): ...
^^^^^^^
SyntaxError: 'yield' outside function
```
Fixes https://github.com/astral-sh/ruff/issues/11118.
Test Plan
--
New inline tests, along with some updates to existing tests.
Summary
--
Detects duplicate attributes in a `match` class pattern:
```python
match x:
case Class(x=1, x=2): ...
```
which are more analogous to the similar check for mapping patterns than
to the
multiple assignments rule.
I also realized that both this and the mapping check would only work on
top-level patterns, despite the possibility that they can be nested
inside other
patterns:
```python
match x:
case [{"x": 1, "x": 2}]: ... # false negative in the old version
```
and moved these checks into the recursive pattern visitor instead.
I also tidied up some of the names like the `multiple_case_assignment`
function
and the `MultipleCaseAssignmentVisitor`, which are now doing more than
checking
for multiple assignments.
Test Plan
--
New inline tests for both classes and mappings.
Summary
--
Fixes#17181. The cases being tested with multiple *keys* being equal
are actually a slightly different error, more like the error for
`MatchMapping` than like the other multiple assignment errors:
```pycon
>>> match x:
... case Class(x=x, x=x): ...
...
File "<python-input-249>", line 2
case Class(x=x, x=x): ...
^
SyntaxError: attribute name repeated in class pattern: x
>>> match x:
... case {"x": 1, "x": 2}: ...
...
File "<python-input-251>", line 2
case {"x": 1, "x": 2}: ...
^^^^^^^^^^^^^^^^
SyntaxError: mapping pattern checks duplicate key ('x')
>>> match x:
... case [x, x]: ...
...
File "<python-input-252>", line 2
case [x, x]: ...
^
SyntaxError: multiple assignments to name 'x' in pattern
```
This PR just stops the false positive reported in the issue, but I will
quickly follow it up with a new rule (or possibly combined with the
mapping rule) catching the repeated attributes separately.
Test Plan
--
New inline `test_ok` and updating the `test_err` cases to have duplicate
values instead of keys.
Summary
--
Detects duplicate literals in `match` mapping keys.
This PR also adds a `source` method to `SemanticSyntaxContext` to
display the duplicated key in the error message by slicing out its
range.
Test Plan
--
New inline tests.
Summary
--
This PR reimplements
[load-before-global-declaration
(PLE0118)](https://docs.astral.sh/ruff/rules/load-before-global-declaration/)
as a semantic syntax error.
I added a `global` method to the `SemanticSyntaxContext` trait to make
this very easy, at least in ruff. Does red-knot have something similar?
If this approach will also work in red-knot, I think some of the other
PLE rules are also compile-time errors in CPython, PLE0117 in
particular. 0115 and 0116 also mention `SyntaxError`s in their docs, but
I haven't confirmed them in the REPL yet.
Test Plan
--
Existing linter tests for PLE0118. I think this actually can't be tested
very easily in an inline test because the `TestContext` doesn't have a
real way to track globals.
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
Summary
--
Fixes https://github.com/astral-sh/ruff/issues/16520 by flagging single,
starred expressions in `return`, `yield`, and
`for` statements.
I thought `yield from` would also be included here, but that error is
emitted by
the CPython parser:
```pycon
>>> ast.parse("def f(): yield from *x")
Traceback (most recent call last):
File "<python-input-214>", line 1, in <module>
ast.parse("def f(): yield from *x")
~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/lib/python3.13/ast.py", line 54, in parse
return compile(source, filename, mode, flags,
_feature_version=feature_version, optimize=optimize)
File "<unknown>", line 1
def f(): yield from *x
^
SyntaxError: invalid syntax
```
And we also already catch it in our parser.
Test Plan
--
New inline tests and updates to existing tests.
Summary
--
Detects starred assignment targets outside of tuples and lists like `*a
= (1,)`.
This PR only considers assignment statements. I also checked annotated
assigment statements, but these give a separate error that we already
catch, so I think they're okay not to consider:
```pycon
>>> *a: list[int] = []
File "<python-input-72>", line 1
*a: list[int] = []
^
SyntaxError: invalid syntax
```
Fixes#13759
Test Plan
--
New inline tests, plus a new `SemanticSyntaxError` for an existing
parser test. I also removed a now-invalid case from an otherwise-valid
test fixture.
The new semantic error leads to two errors for the case below:
```python
*foo() = 42
```
but this matches [pyright] too.
[pyright]: https://pyright-play.net/?code=FQMw9mAUCUAEC8sAsAmAUEA
Summary
--
Detect setting or deleting `__debug__`. Assigning to `__debug__` was a
`SyntaxError` on the earliest version I tested (3.8). Deleting
`__debug__` was made a `SyntaxError` in [BPO 45000], which said it was
resolved in Python 3.10. However, `del __debug__` was also a runtime
error (`NameError`) when I tested in Python 3.9.6, so I thought it was
worth including 3.9 in this check.
I don't think it was ever a *good* idea to try `del __debug__`, so I
think there's also an argument for not making this version-dependent at
all. That would only simplify the implementation very slightly, though.
[BPO 45000]: https://github.com/python/cpython/issues/89163
Test Plan
--
New inline tests. This also required adding a `PythonVersion` field to
the `TestContext` that could be taken from the inline `ParseOptions` and
making the version field on the options accessible.
Summary
--
This PR detects multiple assignments to the same name in `case` patterns
by recursively visiting each pattern.
Test Plan
--
New inline tests.
Summary
--
Detects irrefutable `match` cases before the final case using a modified
version
of the existing `Pattern::is_irrefutable` method from the AST crate. The
modified method helps to retrieve a more precise diagnostic range to
match what
Python 3.13 shows in the REPL.
Test Plan
--
New inline tests, as well as some updates to existing tests that had
irrefutable
patterns before the last block.
Summary
--
Fixes#16943 by checking if the tuple is not parenthesized before
emitting an error.
Test Plan
--
New inline test based on the initial report
Summary
--
Detects duplicate type parameter names in function definitions, class
definitions, and type alias statements.
I also boxed the `type_params` field on `StmtTypeAlias` to make it
easier to
`match` with functions and classes. (That's the reason for the red-knot
code
owner review requests, sorry!)
Test Plan
--
New `ruff_python_syntax_errors` unit tests.
Fixes#11119.
## Summary
This PR implements the "greeter" approach for checking the AST for
syntax errors emitted by the CPython compiler. It introduces two main
infrastructural changes to support all of the compile-time errors:
1. Adds a new `semantic_errors` module to the parser crate with public
`SemanticSyntaxChecker` and `SemanticSyntaxError` types
2. Embeds a `SemanticSyntaxChecker` in the `ruff_linter::Checker` for
checking these errors in ruff
As a proof of concept, it also implements detection of two syntax
errors:
1. A reimplementation of
[`late-future-import`](https://docs.astral.sh/ruff/rules/late-future-import/)
(`F404`)
2. Detection of rebound comprehension iteration variables
(https://github.com/astral-sh/ruff/issues/14395)
## Test plan
Existing F404 tests, new inline tests in the `ruff_python_parser` crate,
and a linter CLI test showing an example of the `Message` output.
I also tested in VS Code, where `preview = false` and turning off syntax
errors both disable the new errors:
And on the playground, where `preview = false` also disables the errors:
Fixes#14395
---------
Co-authored-by: Micha Reiser <micha@reiser.io>
## Summary
This change continues to resolve#16071 (and continues the work started
in #16162). Specifically, this PR changes the code in the parser so that
it uses the `OperatorPrecedence` struct from `ruff_python_ast` instead
of its own version. This is part of an effort to get rid of the
redundant definitions of `OperatorPrecedence` throughout the codebase.
Note that this PR only makes this change for `ruff_python_parser` -- we
still want to make a similar change for the formatter (namely the
`OperatorPrecedence` defined in the expression part of the formatter,
the pattern one is different). I separated the work to keep the PRs
small and easily reviewable.
## Test Plan
Because this is an internal change, I didn't add any additional tests.
Existing tests do pass.
Summary
--
Fixes#16874. I previously emitted a syntax error when starred
annotations were _allowed_ rather than when they were actually used.
This caused false positives for any starred parameter name because these
are allowed to have starred annotations but not required to. The fix is
to check if the annotation is actually starred after parsing it.
Test Plan
--
New inline parser tests derived from the initial report and more
examples from the comments, although I think the first case should cover
them all.
## Summary
This PR detects the use of PEP 701 f-strings before 3.12. This one
sounded difficult and ended up being pretty easy, so I think there's a
good chance I've over-simplified things. However, from experimenting in
the Python REPL and checking with [pyright], I think this is correct.
pyright actually doesn't even flag the comment case, but Python does.
I also checked pyright's implementation for
[quotes](98dc4469cc/packages/pyright-internal/src/analyzer/checker.ts (L1379-L1398))
and
[escapes](98dc4469cc/packages/pyright-internal/src/analyzer/checker.ts (L1365-L1377))
and think I've approximated how they do it.
Python's error messages also point to the simple approach of these
characters simply not being allowed:
```pycon
Python 3.11.11 (main, Feb 12 2025, 14:51:05) [Clang 19.1.6 ] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> f'''multiline {
... expression # comment
... }'''
File "<stdin>", line 3
}'''
^
SyntaxError: f-string expression part cannot include '#'
>>> f'''{not a line \
... continuation}'''
File "<stdin>", line 2
continuation}'''
^
SyntaxError: f-string expression part cannot include a backslash
>>> f'hello {'world'}'
File "<stdin>", line 1
f'hello {'world'}'
^^^^^
SyntaxError: f-string: expecting '}'
```
And since escapes aren't allowed, I don't think there are any tricky
cases where nested quotes or comments can sneak in.
It's also slightly annoying that the error is repeated for every nested
quote character, but that also mirrors pyright, although they highlight
the whole nested string, which is a little nicer. However, their check
is in the analysis phase, so I don't think we have such easy access to
the quoted range, at least without adding another mini visitor.
## Test Plan
New inline tests
[pyright]:
https://pyright-play.net/?pythonVersion=3.11&strict=true&code=EYQw5gBAvBAmCWBjALgCgO4gHaygRgEoAoEaCAIgBpyiiBiCLAUwGdknYIBHAVwHt2LIgDMA5AFlwSCJhwAuCAG8IoMAG1Rs2KIC6EAL6iIxosbPmLlq5foRWiEAAcmERAAsQAJxAomnltY2wuSKogA6WKIAdABWfPBYqCAE%2BuSBVqbpWVm2iHwAtvlMWMgB2ekiolUAgq4FjgA2TAAeEMieSADWCsoV5qoaqrrGDJ5MiDz%2B8ABuLqosAIREhlXlaybrmyYMXsDw7V4AnoysyAmQ5SIhwYo3d9cheADUeKlv5O%2BpQA
## Summary
A small followup to https://github.com/astral-sh/ruff/pull/16386. We now
tell the user exactly what it was about their decorator that constituted
invalid syntax on Python <3.9, and the range now highlights the specific
sub-expression that is invalid rather than highlighting the whole
decorator
## Test Plan
Inline snapshots are updated, and new ones are added.
## Summary
This PR detects unparenthesized assignment expressions used in set
literals and comprehensions and in sequence indexes. The link to the
release notes in https://github.com/astral-sh/ruff/issues/6591 just has
this entry:
> * Assignment expressions can now be used unparenthesized within set
literals and set comprehensions, as well as in sequence indexes (but not
slices).
with no other information, so hopefully the test cases I came up with
cover all of the changes. I also tested these out in the Python REPL and
they actually worked in Python 3.9 too. I'm guessing this may be another
case that was "formally made part of the language spec in Python 3.10,
but usable -- and commonly used -- in Python >=3.9" as @AlexWaygood
added to the body of #6591 for context managers. So we may want to
change the version cutoff, but I've gone along with the release notes
for now.
## Test Plan
New inline parser tests and linter CLI tests.
Summary
--
This is closely related to (and stacked on)
https://github.com/astral-sh/ruff/pull/16544 and detects star
annotations in function definitions.
I initially called the variant `StarExpressionInAnnotation` to mirror
`StarExpressionInIndex`, but I realized it's not really a "star
expression" in this position and renamed it. `StarAnnotation` seems in
line with the PEP.
Test Plan
--
Two new inline tests. It looked like there was pretty good existing
coverage of this syntax, so I just added simple examples to test the
version cutoff.
Summary
--
This PR reuses a slightly modified version of the
`check_tuple_unpacking` method added for detecting unpacking in `return`
and `yield` statements to detect the same issue in the iterator clause
of `for` loops.
I ran into the same issue with a bare `for x in *rest: ...` example
(invalid even on Python 3.13) and added it as a comment on
https://github.com/astral-sh/ruff/issues/16520.
I considered just making this an additional `StarTupleKind` variant as
well, but this change was in a different version of Python, so I kept it
separate.
Test Plan
--
New inline tests.
Summary
--
Unlike the other syntax errors detected so far, parenthesized keyword
arguments are only allowed *before* 3.8. It sounds like they were only
accidentally allowed before that [^1].
As an aside, you get a pretty confusing error from Python for this, so
it's nice that we can catch it:
```pycon
>>> def f(**kwargs): ...
... f((a)=1)
...
File "<python-input-0>", line 2
f((a)=1)
^^^
SyntaxError: expression cannot contain assignment, perhaps you meant "=="?
>>>
```
Test Plan
--
Inline tests.
[^1]: https://github.com/python/cpython/issues/78822
Summary
--
Checks for tuple unpacking in `return` and `yield` statements before
Python 3.8, as described [here].
Test Plan
--
Inline tests.
[here]: https://github.com/python/cpython/issues/76298
Summary
--
Another simple one, just detect type parameter lists in functions
and classes. Like pyright, we don't emit a second diagnostic for
`type` alias statements, which were also introduced in 3.12.
Test Plan
--
Inline tests.
Summary
--
Detects the presence of a [PEP 696] type parameter default before Python
3.13.
Test Plan
--
New inline parser tests for type aliases, generic functions and generic
classes.
[PEP 696]: https://peps.python.org/pep-0696/#grammar-changes
Summary
--
This is a follow-up to #16446 to fix the diagnostic range to point to
the `*` like `pyright` does
(https://github.com/astral-sh/ruff/pull/16446#discussion_r1976900643).
Storing the range in the `ExceptClauseKind::Star` variant feels slightly
awkward, but we don't store the star itself anywhere on the
`ExceptHandler`. And we can't just take `ExceptHandler.start() +
"except".text_len()` because this code appears to be valid:
```python
try: ...
except * Error: ...
```
Test Plan
--
Existing tests.
Summary
--
This is a follow up addressing the comments on #16425. As @dhruvmanila
pointed out, the naming is a bit tricky. I went with `has_no_errors` to
try to differentiate it from `is_valid`. It actually ends up negated in
most uses, so it would be more convenient to have `has_any_errors` or
`has_errors`, but I thought it would sound too much like the opposite of
`is_valid` in that case. I'm definitely open to suggestions here.
Test Plan
--
Existing tests.
## Summary
This PR is the first in a series derived from
https://github.com/astral-sh/ruff/pull/16308, each of which add support
for detecting one version-related syntax error from
https://github.com/astral-sh/ruff/issues/6591. This one should be
the largest because it also includes the addition of the
`Parser::add_unsupported_syntax_error` method
Otherwise I think the general structure will be the same for each syntax
error:
* Detecting the error in the parser
* Inline parser tests for the new error
* New ruff CLI tests for the new error
## Test Plan
As noted above, there are new inline parser tests, as well as new ruff
CLI
tests. Once https://github.com/astral-sh/ruff/pull/16379 is resolved,
there should also be new mdtests for red-knot,
but this PR does not currently include those.
## Summary
This PR adds support for a pragma-style header for inline parser tests
containing JSON-serialized `ParseOptions`. For example,
```python
# parse_options: { "target-version": "3.9" }
match 2:
case 1:
pass
```
The line must start with `# parse_options: ` and then the rest of the
(trimmed) line is deserialized into `ParseOptions` used for parsing the
the test.
## Test Plan
Existing inline tests, plus two new inline tests for
`match-before-py310`.
---------
Co-authored-by: Alex Waygood <alex.waygood@gmail.com>
## Summary
This is part of the preparation for detecting syntax errors in the
parser from https://github.com/astral-sh/ruff/pull/16090/. As suggested
in [this
comment](https://github.com/astral-sh/ruff/pull/16090/#discussion_r1953084509),
I started working on a `ParseOptions` struct that could be stored in the
parser. For this initial refactor, I only made it hold the existing
`Mode` option, but for syntax errors, we will also need it to have a
`PythonVersion`. For that use case, I'm picturing something like a
`ParseOptions::with_python_version` method, so you can extend the
current calls to something like
```rust
ParseOptions::from(mode).with_python_version(settings.target_version)
```
But I thought it was worth adding `ParseOptions` alone without changing
any other behavior first.
Most of the diff is just updating call sites taking `Mode` to take
`ParseOptions::from(Mode)` or those taking `PySourceType`s to take
`ParseOptions::from(PySourceType)`. The interesting changes are in the
new `parser/options.rs` file and smaller parts of `parser/mod.rs` and
`ruff_python_parser/src/lib.rs`.
## Test Plan
Existing tests, this should not change any behavior.
This update includes some missing `^` in the diagnostic annotations.
This update also includes some shifting of "syntax error" annotations to
the end of the preceding line. I believe this is technically a
regression, but fixing them has proven quite difficult. I *think* the
best way to do that might be to tweak the spans generated by the Python
parser errors, but I didn't want to dig into that. (Another approach
would be to change the `annotate-snippets` rendering, but when I tried
that and managed to fix these regressions, I ended up causing a bunch of
other regressions.)
Ref 77d454525e (r1915458616)
We do this because `...` is valid Python, which makes it pretty likely
that some line trimming will lead to ambiguous output. So we add support
for overriding the cut indicator. This also requires changing some of
the alignment math, which was previously tightly coupled to `...`.
For Ruff, we go with `…` (`U+2026 HORIZONTAL ELLIPSIS`) for our cut
indicator.
For more details, see the patch sent to upstream:
https://github.com/rust-lang/annotate-snippets-rs/pull/172
This looks like a bug fix that occurs when the annotation is a
zero-width span immediately following a line terminator. Previously, the
caret seems to be rendered on the next line, but it should be rendered
at the end of the line the span corresponds to.
I admit that this one is kinda weird. I would somewhat expect that our
spans here are actually incorrect, and that to obtain this sort of
rendering, we should identify a span just immediately _before_ the line
terminator and not after it. But I don't want to dive into that rabbit
hole for now (and given how `annotate-snippets` now renders these
spans, perhaps there is more to it than I see), and this does seem like
a clear improvement given the spans we feed to `annotate-snippets`.
The previous rendering just seems wrong in that a `^` is omitted. The
new version of `annotate-snippets` seems to get this right. I checked a
pseudo random sample of these, and it seems to only happen when the
position pointed at a line terminator.
These updates center around the addition of annotations in the
diagnostic rendering. Previously, the annotation was just not rendered
at all. With the `annotate-snippets` upgrade, it is now rendered. I
examined a pseudo random sample of these, and they all look correct.
As will be true in future batches, some of these snapshots also have
changes to whitespace in them as well.
These snapshot changes should *all* only be a result of changes to
trailing whitespace in the output. I checked a psuedo random sample of
these, and the whitespace found in the previous snapshots seems to be an
artifact of the rendering and _not_ of the source data. So this seems
like a strict bug fix to me.
There are other snapshots with whitespace changes, but they also have
other changes that we split out into separate commits. Basically, we're
going to do approximately one commit per category of change.
This represents, by far, the biggest chunk of changes to snapshots as a
result of the `annotate-snippets` upgrade.
This is pretty much just moving to the new API and taking care to use
byte offsets. This is *almost* enough. The next commit will fix a bug
involving the handling of unprintable characters as a result of
switching to byte offsets.
When confronted with `raise from exc` the parser will now create a
`StmtRaise` that has `None` for the exception and `exc` for the cause.
Before, the parser created a `StmtRaise` with `from` for the exception,
no cause, and a spurious expression `exc` afterwards.
