* A basic StmtAssign formatter and better dummies for expressions
The goal of this PR was formatting StmtAssign since many nodes in the black tests (and in python in general) are after an assignment. This caused unstable formatting: The spacing of power op spacing depends on the type of the two involved expressions, but each expression was formatted as dummy string and re-parsed as a ExprName, so in the second round the different rules of ExprName were applied, causing unstable formatting.
This PR does not necessarily bring us closer to black's style, but it unlocks a good porting of black's test suite and is a basis for implementing the Expr nodes.
* fmt
* Review
* Use phf for confusables to reduce llvm lines
## Summary
This replaces FxHashMap for the confusables with a perfect hash map from the [phf crate](https://github.com/rust-phf/rust-phf) to reduce the generated llvm instructions.
A perfect hash function is one that doesn't have any collisions. We can build one because we know all keys at compile time. This improves hashmap efficiency, even though this is likely not noticeable in our case (except someone has a large non-english crate to test on).
The original hashmap contained a lot of duplicates, which i had to remove when phf_map complained, i did so by sorting the keys.
The important part that it reduces the llvm instructions generated (#3808, `RUSTFLAGS="-Csymbol-mangling-version=v0" cargo llvm-lines -p ruff --lib | head -20`):
```
Lines Copies Function name
----- ------ -------------
1740502 38973 (TOTAL)
27423 (1.6%, 1.6%) 1 (0.0%, 0.0%) ruff[cef4c65d96248843]::rules::ruff::rules::confusables::CONFUSABLES::{closure#0}
10193 (0.6%, 2.2%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::codes::RuleCodePrefix>::iter
8107 (0.5%, 2.6%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::codes::Rule>::noqa_code
7345 (0.4%, 3.0%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::checkers::ast::Checker as ruff_python_ast[3778b140caf21545]::visitor::Visitor>::visit_stmt
6412 (0.4%, 3.4%) 1 (0.0%, 0.0%) <<ruff[cef4c65d96248843]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_map::<toml_edit[7e3a6c5e67260672]:🇩🇪:spanned::SpannedDeserializer<toml_edit[7e3a6c5e67260672]:🇩🇪:value::ValueDeserializer>>
6412 (0.4%, 3.8%) 1 (0.0%, 0.0%) <<ruff[cef4c65d96248843]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_map::<toml_edit[7e3a6c5e67260672]:🇩🇪:table::TableMapAccess>
6409 (0.4%, 4.2%) 1 (0.0%, 0.0%) <<ruff[cef4c65d96248843]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_map::<toml_edit[7e3a6c5e67260672]:🇩🇪:datetime::DatetimeDeserializer>
5696 (0.3%, 4.5%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::checkers::ast::Checker as ruff_python_ast[3778b140caf21545]::visitor::Visitor>::visit_expr
4448 (0.3%, 4.7%) 1 (0.0%, 0.0%) ruff[cef4c65d96248843]::flake8_to_ruff::converter::convert
3702 (0.2%, 4.9%) 1 (0.0%, 0.0%) <&ruff[cef4c65d96248843]::registry::Linter as core[da82827a87f140f9]::iter::traits::collect::IntoIterator>::into_iter
3349 (0.2%, 5.1%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::registry::Linter>::code_for_rule
3132 (0.2%, 5.3%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::codes::Rule as core[da82827a87f140f9]::fmt::Debug>::fmt
3130 (0.2%, 5.5%) 1 (0.0%, 0.0%) <&str as core[da82827a87f140f9]::convert::From<&ruff[cef4c65d96248843]::codes::Rule>>::from
3130 (0.2%, 5.7%) 1 (0.0%, 0.0%) <&str as core[da82827a87f140f9]::convert::From<ruff[cef4c65d96248843]::codes::Rule>>::from
3130 (0.2%, 5.9%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::codes::Rule as core[da82827a87f140f9]::convert::AsRef<str>>::as_ref
3128 (0.2%, 6.0%) 1 (0.0%, 0.0%) <ruff[cef4c65d96248843]::codes::RuleIter>::get
2669 (0.2%, 6.2%) 1 (0.0%, 0.0%) <<ruff[cef4c65d96248843]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_seq::<toml_edit[7e3a6c5e67260672]:🇩🇪:array::ArraySeqAccess>
```
After:
```
Lines Copies Function name
----- ------ -------------
1710487 38900 (TOTAL)
10193 (0.6%, 0.6%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::codes::RuleCodePrefix>::iter
8107 (0.5%, 1.1%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::codes::Rule>::noqa_code
7345 (0.4%, 1.5%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::checkers::ast::Checker as ruff_python_ast[5588cd60041c8605]::visitor::Visitor>::visit_stmt
6412 (0.4%, 1.9%) 1 (0.0%, 0.0%) <<ruff[52408f46d2058296]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_map::<toml_edit[7e3a6c5e67260672]:🇩🇪:spanned::SpannedDeserializer<toml_edit[7e3a6c5e67260672]:🇩🇪:value::ValueDeserializer>>
6412 (0.4%, 2.2%) 1 (0.0%, 0.0%) <<ruff[52408f46d2058296]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_map::<toml_edit[7e3a6c5e67260672]:🇩🇪:table::TableMapAccess>
6409 (0.4%, 2.6%) 1 (0.0%, 0.0%) <<ruff[52408f46d2058296]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_map::<toml_edit[7e3a6c5e67260672]:🇩🇪:datetime::DatetimeDeserializer>
5696 (0.3%, 3.0%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::checkers::ast::Checker as ruff_python_ast[5588cd60041c8605]::visitor::Visitor>::visit_expr
4448 (0.3%, 3.2%) 1 (0.0%, 0.0%) ruff[52408f46d2058296]::flake8_to_ruff::converter::convert
3702 (0.2%, 3.4%) 1 (0.0%, 0.0%) <&ruff[52408f46d2058296]::registry::Linter as core[da82827a87f140f9]::iter::traits::collect::IntoIterator>::into_iter
3349 (0.2%, 3.6%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::registry::Linter>::code_for_rule
3132 (0.2%, 3.8%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::codes::Rule as core[da82827a87f140f9]::fmt::Debug>::fmt
3130 (0.2%, 4.0%) 1 (0.0%, 0.0%) <&str as core[da82827a87f140f9]::convert::From<&ruff[52408f46d2058296]::codes::Rule>>::from
3130 (0.2%, 4.2%) 1 (0.0%, 0.0%) <&str as core[da82827a87f140f9]::convert::From<ruff[52408f46d2058296]::codes::Rule>>::from
3130 (0.2%, 4.4%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::codes::Rule as core[da82827a87f140f9]::convert::AsRef<str>>::as_ref
3128 (0.2%, 4.5%) 1 (0.0%, 0.0%) <ruff[52408f46d2058296]::codes::RuleIter>::get
2669 (0.2%, 4.7%) 1 (0.0%, 0.0%) <<ruff[52408f46d2058296]::settings::options::Options as serde[d89b1b632568f5a3]:🇩🇪:Deserialize>::deserialize::__Visitor as serde[d89b1b632568f5a3]:🇩🇪:Visitor>::visit_seq::<toml_edit[7e3a6c5e67260672]:🇩🇪:array::ArraySeqAccess>
2659 (0.2%, 4.9%) 1 (0.0%, 0.0%) <&ruff[52408f46d2058296]::codes::Pylint as core[da82827a87f140f9]::iter::traits::collect::IntoIterator>::into_iter
```
I'd assume this has a positive effect both on compile time and on runtime, but i don't know the actual effect on compile times and can't really measure.
## Test plan
Check CI for any performance regressions.
This should fix#3808 if we merge it.
* clippy
* Update update_ambiguous_characters.py
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## Summary
This PR replaces the `verbatim_text` builder with a `not_yet_implemented` builder that emits `NOT_YET_IMPLEMENTED_<NodeKind>` for not yet implemented nodes.
The motivation for this change is that partially formatting compound statements can result in incorrectly indented code, which is a syntax error:
```python
def func_no_args():
a; b; c
if True: raise RuntimeError
if False: ...
for i in range(10):
print(i)
continue
```
Get's reformatted to
```python
def func_no_args():
a; b; c
if True: raise RuntimeError
if False: ...
for i in range(10):
print(i)
continue
```
because our formatter does not yet support `for` statements and just inserts the text from the source.
## Downsides
Using an identifier will not work in all situations. For example, an identifier is invalid in an `Arguments ` position. That's why I kept `verbatim_text` around and e.g. use it in the `Arguments` formatting logic where incorrect indentations are impossible (to my knowledge). Meaning, `verbatim_text` we can opt in to `verbatim_text` when we want to iterate quickly on nodes that we don't want to provide a full implementation yet and using an identifier would be invalid.
## Upsides
Running this on main discovered stability issues with the newline handling that were previously "hidden" because of the verbatim formatting. I guess that's an upside :)
## Test Plan
None?
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## Summary
This issue fixes the removal of empty lines between a leading comment and the previous statement:
```python
a = 20
# leading comment
b = 10
```
Ruff removed the empty line between `a` and `b` because:
* The leading comments formatting does not preserve leading newlines (to avoid adding new lines at the top of a body)
* The `JoinNodesBuilder` counted the lines before `b`, which is 1 -> Doesn't insert a new line
This is fixed by changing the `JoinNodesBuilder` to count the lines instead *after* the last node. This correctly gives 1, and the `# leading comment` will insert the empty lines between any other leading comment or the node.
## Test Plan
I added a new test for empty lines.
According to https://docs.python.org/3/library/ast.html#ast-helpers, we expect type_ignores to be always be empty, so this adds a debug assert.
Test plan: I confirmed that the assertion holdes for the file below and for all the black tests which include a number of `type: ignore` comments.
```python
# type: ignore
if 1:
print("1") # type: ignore
# elsebranch
# type: ignore
else: # type: ignore
print("2") # type: ignore
while 1:
print()
# type: ignore
```
* Implement module formatting using JoinNodesBuilder
This uses JoinNodesBuilder to implement module formatting for #4800
See the snapshots for the changed behaviour. See one PR up for a CLI that i used to verify the trailing new line behaviour
* Add a formatter CLI for debugging
This adds a ruff_python_formatter cli modelled aber `rustfmt` that i use for debugging
* clippy
* Add print IR and print comments options
Tested with `cargo run --bin ruff_python_formatter -- --print-ir --print-comments scratch.py`
