## Summary
After #5140, I audited the codebase for similar patterns (defining a
list of `CallPath` entities in a static vector, then looping over them
to pattern-match). This PR migrates all other such cases to use `match`
and `matches!` where possible.
There are a few benefits to this:
1. It more clearly denotes the intended semantics (branches are
exclusive).
2. The compiler can help deduplicate the patterns and detect unreachable
branches.
3. Performance: in the benchmark below, the all-rules performance is
increased by nearly 10%...
## Benchmarks
I decided to benchmark against a large file in the Airflow repository
with a lot of type annotations
([`views.py`](https://raw.githubusercontent.com/apache/airflow/f03f73100e8a7d6019249889de567cb00e71e457/airflow/www/views.py)):
```
linter/default-rules/airflow/views.py
time: [10.871 ms 10.882 ms 10.894 ms]
thrpt: [19.739 MiB/s 19.761 MiB/s 19.781 MiB/s]
change:
time: [-2.7182% -2.5687% -2.4204%] (p = 0.00 < 0.05)
thrpt: [+2.4805% +2.6364% +2.7942%]
Performance has improved.
linter/all-rules/airflow/views.py
time: [24.021 ms 24.038 ms 24.062 ms]
thrpt: [8.9373 MiB/s 8.9461 MiB/s 8.9527 MiB/s]
change:
time: [-8.9537% -8.8516% -8.7527%] (p = 0.00 < 0.05)
thrpt: [+9.5923% +9.7112% +9.8342%]
Performance has improved.
Found 12 outliers among 100 measurements (12.00%)
5 (5.00%) high mild
7 (7.00%) high severe
```
The impact is dramatic -- nearly a 10% improvement for `all-rules`.
## Summary
I noticed that we have a few hot comparisons that involve called
`s.to_lowercase()`. We can avoid an allocation by comparing characters
directly.
This adds a new rule `InvalidPyprojectToml` that lints pyproject.toml by checking if https://github.com/PyO3/pyproject-toml-rs can parse it. This means the linting is currently very basic, e.g. we don't check whether the name is actually a valid python project name or appropriately normalized. It does catch errors e.g. with invalid dependency requirements or problems withs the license specifications. It is open to be extended in the future (validate name, SPDX expressions, classifiers, ...), either in ruff or in pyproject-toml-rs.
Test plan:
```
scripts/ecosystem_all_check.sh check --select RUF200
```
This lead to a bunch of
```
RUF200 Failed to parse pyproject.toml: missing field `name`
```
(e.g. https://github.com/amitsk/fastapi-todos/blob/main/pyproject.toml) which is indeed invalid (https://packaging.python.org/en/latest/specifications/declaring-project-metadata/#specification).
Filtering those out, the following other problems were found by `cd target/ecosystem_all_results/ && rg RUF200`:
```
UCL-ARC:rred-reports.stdout.txt
1:pyproject.toml:27:16: RUF200 Failed to parse pyproject.toml: Version specifier `>='3.9'` doesn't match PEP 440 rules
EndlessTrax:python-start-project.stdout.txt
1:pyproject.toml:14:16: RUF200 Failed to parse pyproject.toml: Expected package name starting with an alphanumeric character, found '#'
redjax:gardening-api.stdout.txt
1:pyproject.toml:7:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
ajslater:codex.stdout.txt
2: 3:17 RUF200 Failed to parse pyproject.toml: invalid type: sequence, expected a string
LDmitriy7:404_AvatarsBot.stdout.txt
1:pyproject.toml:3:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
ajslater:comicbox.stdout.txt
1:pyproject.toml:3:17: RUF200 Failed to parse pyproject.toml: invalid type: sequence, expected a string
manueldevillena:forecast-earnings.stdout.txt
1:pyproject.toml:24:12: RUF200 Failed to parse pyproject.toml: Expected one of `@`, `(`, `<`, `=`, `>`, `~`, `!`, `;`, found `^`
redjax:ohio_utility_scraper.stdout.txt
1:pyproject.toml:11:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
agronholm:typeguard.stdout.txt
1:pyproject.toml:40:8: RUF200 Failed to parse pyproject.toml: Expected a valid marker name, found 'python_implementation'
cyuss:decathlon-turnover.stdout.txt
1:pyproject.toml:7:12: RUF200 Failed to parse pyproject.toml: invalid type: string "Youcef", expected a table with 'name' and 'email' keys
ajslater:boilerplate.stdout.txt
1:pyproject.toml:3:17: RUF200 Failed to parse pyproject.toml: invalid type: sequence, expected a string
kaparoo:lightning-project-template.stdout.txt
1:pyproject.toml:56:16: RUF200 Failed to parse pyproject.toml: You can't mix a >= operator with a local version (`+cu117`)
dijital20:pytexas2023-decorators.stdout.txt
1:pyproject.toml:5:11: RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
pfouque:django-anymail-history.stdout.txt
1:pyproject.toml:137:12: RUF200 Failed to parse pyproject.toml: Version specifier `> = 1.2.0` doesn't match PEP 440 rules
pfouque:django-fakemessages.stdout.txt
1:pyproject.toml:130:12: RUF200 Failed to parse pyproject.toml: Version specifier `> = 1.2.0` doesn't match PEP 440 rules
pypa:build.stdout.txt
1:tests/packages/test-invalid-requirements/pyproject.toml:2:12: RUF200 Failed to parse pyproject.toml: Expected one of `@`, `(`, `<`, `=`, `>`, `~`, `!`, `;`, found `i`
4:tests/packages/test-no-requires/pyproject.toml:1:1: RUF200 Failed to parse pyproject.toml: missing field `requires`
UnoYakshi:FRAAND.stdout.txt
2: 3:11 RUF200 Failed to parse pyproject.toml: Version `` doesn't match PEP 440 rules
DHolmanCoding:python-template.stdout.txt
1:pyproject.toml:22:1: RUF200 Failed to parse pyproject.toml: missing field `requires`
```
Overall, this emitted errors in 43 out of 3408 projects (`rg -c RUF200 target/ecosystem_all_results/ | wc -l`)
Co-authored-by: Micha Reiser <micha@reiser.io>
In hindsight, `ruff_python` is too general. A good giveaway is that it's actually a prefix of some other crates. The intent of this crate is to reimplement pieces of the Python standard library and CPython itself, so `ruff_python_stdlib` feels appropriate.
