Exclude failure for tool.ruff[lint|format]

[dhruvmanila]

Detected here: #8240 (comment)

With the following directory structure:

.
├── pyproject.toml [1]
└── tests
    └── packages
        └── test-bad-syntax
            └── pyproject.toml [2]

And, in pyproject.toml at

[1]

[tool.ruff.lint]
exclude = ["tests/packages/test-bad-syntax"]

[2]

[build-system]
requires = ['bad' 'syntax']

Running the command:

$ ruff check .  
ruff failed
  Cause: TOML parse error at line 2, column 19
  |
2 | requires = ['bad' 'syntax']
  |                   ^
invalid array
expected `]`

With:

$ ruff version
ruff 0.1.2 (3127c79b2 2023-10-24)

It works with [tool.ruff]. The main branch fails as well.

[MichaReiser]

I think the issue here is that exclude and lint.exclude are semantically different.

• exclude: Excludes files from discovery.
• lint.exclude: Excludes files from linting.

The proper fix is to change their configuration to use exclude instead of lint.exclude.

[MichaReiser]

See: pypa/build#697 I asked if we could improve our documentation to make the distinction more clear.

[charliermarsh]

But it still feels like lint.exclude should respect the same semantics for exclusion, no?

[MichaReiser]

But it still feels like lint.exclude should respect the same semantics for exclusion, no?

I wouldn't know how that would work in a unified check command. The way it would work there is:

• Ruff detects all files, only respecting exclude
• Ruff calls lint for files not in exclude or lint.exclude
• Ruff calls format for files not in exclude or format.exclude

Applying the same semantics in lint.exclude would mean that it is necessary to run file discovery twice, once for exclude merged with lint.exclude and once with format merged with format.exclude. This would remove all benefits of having a single toolchain because we need to perform file discovery, parsing, setting resolution, etc. twice.

[charliermarsh]

I don't know, but isn't it strange that setting lint.exclude to exclude = ["tests/packages/test-bad-syntax"] doesn't exclude files in ./tests/packages/test-bad-syntax from linting?

[MichaReiser]

I don't know, but isn't it strange that setting lint.exclude to exclude = ["tests/packages/test-bad-syntax"] doesn't exclude files in ./tests/packages/test-bad-syntax from linting?

It does exclude files in test-bad-syntax from linting. The reported problem is that test-bad-syntax contains a pyproject.toml with a syntax error and ruff tries to load it when discovering the python files of the project when using lint.exclude but it does not when adding the directory to exclude.

[charliermarsh]

Hmm, are you sure? I don't believe that's the case, because we're only testing against the file itself, and not its parent directories.

Given:

[tool.ruff.lint]
exclude = ["tests/packages/test-bad-syntax"]

Running:

❯ cargo run -p ruff_cli -- check .
    Finished dev [unoptimized + debuginfo] target(s) in 0.10s
     Running `/Users/crmarsh/workspace/ruff/target/debug/ruff check .`
warning: Detected debug build without --no-cache.
tests/packages/test-bad-syntax/foo.py:1:8: F401 [*] `os` imported but unused
Found 1 error.

If I change the pyproject.toml to:

[tool.ruff.lint]
exclude = ["tests/packages/test-bad-syntax/*.py"]

Then:

❯ cargo run -p ruff_cli -- check .
    Finished dev [unoptimized + debuginfo] target(s) in 0.10s
     Running `/Users/crmarsh/workspace/ruff/target/debug/ruff check .`
warning: Detected debug build without --no-cache.

[MichaReiser]

Hmm interesting. Let's create a new issue for this because this is unrelated to the original report.

#8267

[charliermarsh]

(Sorry, I think I misunderstood the root cause of the reported issue.)