MegaLinter ignores linter config in workspace when LINTER_RULES_PATH is set

[liblaf]

Describe the bug

I am expecting MegaLinter to search for linter config files in the following precedence:

• GITHUB_WORKSPACE
• LINTER_RULES_PATH
• MegaLinter default config

However, MegaLinter seems to ignore config files in workspace when LINTER_RULES_PATH is set.

To Reproduce

Here is the demo workflow run.

Expected behavior

There should be no errors since F401 is ignored in .ruff.toml. However, .ruff.toml under repository root seems not to be used by MegaLinter.

Additional context

Setting PYTHON_RUFF_CONFIG_FILE: LINTER_DEFAULT in .mega-linter.yaml can solve the issue.

[github-actions]

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[nvuillam]

Is the probem still happening ? :)

[liblaf]

@nvuillam Yes. Here is a demo workflow run:

❌ Linted [PYTHON] files with [ruff]: Found 1 error(s) - (0.03s) (expand for details)
  - Using [ruff v0.8.0] https://megalinter.io/8.3.0/descriptors/python_ruff
  - MegaLinter key: [PYTHON_RUFF]
  - Rules config: [https://github.com/liblaf/.github/raw/refs/heads/main/.github/linters/.ruff.toml]
  - Number of files analyzed: [1]
  - Command: [ruff check --fix --no-fix --config /github/workspace/.ruff.toml --output-format sarif --output-file /github/workspace/megalinter-reports/sarif/PYTHON_RUFF.sarif main.py]
  --Error detail:
  error: `os` imported but unused
  
  error: 1 errors emitted

Note the message Rules config: ..., you can see that MegaLinter uses the config from LINTER_RULES_PATH instead of that under GITHUB_WORKSPACE.

Is the .ruff.toml under GITHUB_WORKSPACE overwritten by the one from LINTER_RULES_PATH?