## Summary

If a comma separated list has only one entry, black will respect the
magic trailing comma, but it will not add a new one.

The following code will remain as is:

```python
b1 = [
    aksjdhflsakhdflkjsadlfajkslhfdkjsaldajlahflashdfljahlfksajlhfajfjfsaahflakjslhdfkjalhdskjfa
]
b2 = [
    aksjdhflsakhdflkjsadlfajkslhfdkjsaldajlahflashdfljahlfksajlhfajfjfsaahflakjslhdfkjalhdskjfa,
]
b3 = [
    aksjdhflsakhdflkjsadlfajkslhfdkjsaldajlahflashdfljahlfksajlhfajfjfsaahflakjslhdfkjalhdskjfa,
    aksjdhflsakhdflkjsadlfajkslhfdkjsaldajlahflashdfljahlfksajlhfajfjfsaahflakjslhdfkjalhdskjfa
]
```

## Test Plan

This was first discovered in
https://github.com/django/django/blob/7eeadc82c2f7d7a778e3bb43c34d642e6275dacf/django/contrib/admin/checks.py#L674-L681,
which i've minimized into a call test.

I've added tests for the three cases (one entry + no comma, one entry +
comma, more than one entry) to the list tests.

The diffs from the black tests get smaller.

…5436)

## Summary

As discussed on ~IRC~ Discord, this will make it easier for e.g. the
docs generation stuff to get all rules for a linter (using
`all_rules()`) instead of just non-nursery ones, and it also makes it
more Explicit Is Better Than Implicit to iterate over linter rules.

Grepping for `Item = Rule` reveals some remaining implicit
`IntoIterator`s that I didn't feel were necessarily in scope for this
(and honestly, iterating over a `RuleSet` makes sense).

## Summary

Format import statements in all their variants. Specifically, this
implemented formatting `StmtImport`, `StmtImportFrom` and `Alias`.

## Test Plan

I added some custom snapshots, even though this has been covered well by
black's tests.

)

## Summary

This makes the output of `check-formatter-stability` more concise by
removing extraneous newlines. It also adds a `--error-file` option to
that script that allows creating a file with just the errors (without
the status messages) to share with others.

## Test Plan

I ran it over CPython and looked at the output. I then added the
`--error-file` option and looked at the contents of the file

Co-authored-by: Thomas de Zeeuw <[email protected]>
Co-authored-by: Micha Reiser <[email protected]>

Closes #5505.

Closes #5496.

## Summary

We need to avoid raising "rewrite as a comprehension" violations in
cases like:

```python
d = defaultdict(list)

for i in [1, 2, 3]:
    d[i].append(i**2)
```

Closes #5494.

Closes #5500.

## Summary

Implement Pylint `typevar-name-mismatch` (`C0132`) as
`type-param-name-mismatch` (`PLC0132`). Includes documentation. Related
to #970.

The Pylint implementation checks only `TypeVar`, but this PR checks
`TypeVarTuple`, `ParamSpec`, and `NewType` as well. This seems to better
represent the Pylint rule's [intended
behaviour](pylint-dev/pylint#5224).

Full disclosure: I am not a fan of the translated name and think it
should probably be different.

## Test Plan

`cargo test`

## Summary

The clippy wasm job rarely fails if regular clippy doesn't, wasm clippy
still compiles a lot of native dependencies for the proc macro and we
have less CI jobs overall, so i think this an improvement to our CI.

```shell
$ CARGO_TARGET_DIR=target-wasm cargo clippy -p ruff_wasm --target wasm32-unknown-unknown --all-features -j 2 -- -D warnings
$ du -sh target-wasm/*
12K	target-wasm/CACHEDIR.TAG
582M	target-wasm/debug
268M	target-wasm/wasm32-unknown-unknown
```

## Test plan

n/a

Closes #5495, but there's a TODO here to improve this further. The
current `from_code` implementation feels really indirect.

## Summary

This adds a `ruff rule --all` switch that prints out a human-readable
Markdown or a machine-readable JSON document of the lint rules known to
Ruff.

I needed a machine-readable document of the rules [for a
project](#5078), and
figured it could be useful for other people – or tooling! – to be able
to interrogate Ruff about its arcane knowledge.

The JSON output is an array of the same objects printed by `ruff rule
--format=json`.

## Test Plan

I ran `ruff rule --all --format=json`. I think more might be needed, but
maybe a snapshot test is overkill?

## Summary

No behavior change, but I think this is a little cleaner.

… excludes (#5513)

## Summary

VS Code extensions are
[recommended](https://code.visualstudio.com/docs/python/settings-reference#_linting-settings)
to exclude `.vscode` and `site-packages`. Black also now omits
`.vscode`, `.pytest_cache`, and `.ipynb_checkpoints` by default.
Omitting `.pyenv` is similar to omitting virtual environments, but
really only matters in the context of VS Code (see:
#5509).

Closes: #5510.