--disable-error-code=unused-ignore should override enable_error_code = ["unused-ignore"] #20348

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1. bersbersbers

   added

   bugmypy got something wrongmypy got something wrong

   on Dec 2, 2025
2. wyattscarpenter commented on Dec 2, 2025

   

   wyattscarpenter

   on Dec 2, 2025

   Last edited by wyattscarpenter

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   Yep, https://mypy.readthedocs.io/en/stable/config_file.html#config-file-format ("When options conflict, the precedence order...") specifies that command line options should overrule top-level configuration file options. I haven't looked into this further.
3. A5rocks

   added

   topic-configurationConfiguration files and flagsConfiguration files and flags

   topic-error-reportingHow we report errorsHow we report errors

   on Dec 2, 2025
4. sterliakov commented on Dec 2, 2025

   

   sterliakov

   on Dec 2, 2025

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   Confirmed. It is common knowledge that CLI flags override envvars, and those in turn override configuration file entries (local, then user-level, then global).

   This is not specific to --{en,dis}able-error-code, possibly-undefined suffers from the same problem:

   $ mypy -c $'if 1:a = 1\nprint(a)' --cache-dir=/dev/null
   Success: no issues found in 1 source file
   $ cat <<EOF >pyproject.toml
   [tool.mypy]
   enable_error_code = ["possibly-undefined"]
   EOF
   $ mypy -c $'if 1:a = 1\nprint(a)' --cache-dir=/dev/null
   <string>:2: error: Name "a" may be undefined  [possibly-undefined]
   Found 1 error in 1 file (checked 1 source file)
   $ mypy -c $'if 1:a = 1\nprint(a)' --disable-error-code=possibly-undefined --cache-dir=/dev/null
   <string>:2: error: Name "a" may be undefined  [possibly-undefined]
   Found 1 error in 1 file (checked 1 source file)

   Probably all codes that are disabled by default are affected.

   The ultimate issue is that enable-error-code has lower priority than disable-error-code, so two strategies clash: --disable-error-code should have higher priority because it is passed as argv, but lower priority because we declare so:

   Note: This flag will override disabled error codes from the --disable-error-code flag.

   So if both were provided by the same means (both as CLI flags or both as config file entries), this behaviour would be sound, but not when the priority is clear from the source.
5. franzengel04 commented on Dec 2, 2025

   

   franzengel04

   on Dec 2, 2025

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   Hi! I’m a first-time contributor and I’d like to work on fixing this issue.
   Would adjusting the precedence logic in the CLI/config parser and adding tests to ensure that command-line flags correctly override configuration be an okay approach for me to take on?
6. sterliakov commented on Dec 2, 2025

   

   sterliakov

   on Dec 2, 2025

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   @franzengel04 thanks! Yes, that sounds good to me:)

   👍React with 👍1Reacted by Franz Engel
7. franzengel04

   added 4 commits that reference this issue on Dec 3, 2025

   Fix error code precedence to ensure disable overrides enable

   ...

   This issue will close once commit 2a3dfc5 is merged into the 'master' branch.

   2a3dfc5

   Fix error code precedence to ensure disable overrides enable

   ...

   This issue will close once commit 4d61b4b is merged into the 'master' branch.

   4d61b4b

   Fix: Ensure disable overrides enable in Options.apply_changes

   ...

   This issue will close once commit 4a58c92 is merged into the 'master' branch.

   4a58c92

   Add failing test for per-module error code precedence

   ...

   This issue will close once commit 1e0bf46 is merged into the 'master' branch.

   1e0bf46
8. RiyaPrabhakar-git

   added this to GC-Content-Calculatoron Dec 12, 2025
9. github-project-automation

   moved this to Todo in GC-Content-Calculatoron Dec 12, 2025