[flake8-bugbear] Accept immutable slice default arguments (B008)
#21823
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
ntBre
changed the title
flake8-bugbear] Accept immutable slice default arguments (B008)
ntBre
approved these changes
Dec 8, 2025
Contributor
ntBre
left a comment
ntBre
left a comment
There was a problem hiding this comment.
Thank you!
Just a note in case of future reference, I checked the other callers of is_immutable_return_type (via is_immutable_func), and this change will also affect function-call-in-dataclass-default-argument (RUF009) and mutable-contextvar-default (B039).
But I think it's straightforward enough that we don't need to test every rule.
dcreager
added a commit
that referenced
this pull request
Dec 9, 2025
…return * dcreager/die-die-intersections: (29 commits) simpler bounds [`pylint`] Detect subclasses of builtin exceptions (`PLW0133`) (#21382) Fix stack overflow with recursive generic protocols (depth limit) (#21858) New diagnostics for unused range suppressions (#21783) [ty] Use default settings in completion tests [ty] Infer type variables within generic unions (#21862) [ty] Fix overload filtering to prefer more "precise" match (#21859) [ty] Stabilize auto-import [ty] Fix reveal-type E2E test (#21865) [ty] Use concise message for LSP clients not supporting related diagnostic information (#21850) Include more details in Tokens 'offset is inside token' panic message (#21860) apply range suppressions to filter diagnostics (#21623) [ty] followup: add-import action for `reveal_type` too (#21668) [ty] Enrich function argument auto-complete suggestions with annotated types [ty] Add autocomplete suggestions for function arguments [`flake8-bugbear`] Accept immutable slice default arguments (`B008`) (#21823) [`pydocstyle`] Suppress `D417` for parameters with `Unpack` annotations (#21816) [ty] Remove legacy `concise_message` fallback behavior (#21847) [ty] Make Python-version subdiagnostics less verbose (#21849) [ty] Supress inlay hints when assigning a trivial initializer call (#21848) ...
dcreager
added a commit
that referenced
this pull request
Dec 9, 2025
…return * dcreager/die-die-intersections: (31 commits) clippy reword comment simpler bounds [`pylint`] Detect subclasses of builtin exceptions (`PLW0133`) (#21382) Fix stack overflow with recursive generic protocols (depth limit) (#21858) New diagnostics for unused range suppressions (#21783) [ty] Use default settings in completion tests [ty] Infer type variables within generic unions (#21862) [ty] Fix overload filtering to prefer more "precise" match (#21859) [ty] Stabilize auto-import [ty] Fix reveal-type E2E test (#21865) [ty] Use concise message for LSP clients not supporting related diagnostic information (#21850) Include more details in Tokens 'offset is inside token' panic message (#21860) apply range suppressions to filter diagnostics (#21623) [ty] followup: add-import action for `reveal_type` too (#21668) [ty] Enrich function argument auto-complete suggestions with annotated types [ty] Add autocomplete suggestions for function arguments [`flake8-bugbear`] Accept immutable slice default arguments (`B008`) (#21823) [`pydocstyle`] Suppress `D417` for parameters with `Unpack` annotations (#21816) [ty] Remove legacy `concise_message` fallback behavior (#21847) ...
dcreager
added a commit
that referenced
this pull request
Dec 9, 2025
…return * dcreager/die-die-intersections: (31 commits) clippy reword comment simpler bounds [`pylint`] Detect subclasses of builtin exceptions (`PLW0133`) (#21382) Fix stack overflow with recursive generic protocols (depth limit) (#21858) New diagnostics for unused range suppressions (#21783) [ty] Use default settings in completion tests [ty] Infer type variables within generic unions (#21862) [ty] Fix overload filtering to prefer more "precise" match (#21859) [ty] Stabilize auto-import [ty] Fix reveal-type E2E test (#21865) [ty] Use concise message for LSP clients not supporting related diagnostic information (#21850) Include more details in Tokens 'offset is inside token' panic message (#21860) apply range suppressions to filter diagnostics (#21623) [ty] followup: add-import action for `reveal_type` too (#21668) [ty] Enrich function argument auto-complete suggestions with annotated types [ty] Add autocomplete suggestions for function arguments [`flake8-bugbear`] Accept immutable slice default arguments (`B008`) (#21823) [`pydocstyle`] Suppress `D417` for parameters with `Unpack` annotations (#21816) [ty] Remove legacy `concise_message` fallback behavior (#21847) ...
dcreager
added a commit
that referenced
this pull request
Dec 10, 2025
* origin/main: (33 commits) [ty] Simplify union lower bounds and intersection upper bounds in constraint sets (#21871) [ty] Collapse `never` paths in constraint set BDDs (#21880) Fix leading comment formatting for lambdas with multiple parameters (#21879) [ty] Type inference for `@asynccontextmanager` (#21876) Fix comment placement in lambda parameters (#21868) [`pylint`] Detect subclasses of builtin exceptions (`PLW0133`) (#21382) Fix stack overflow with recursive generic protocols (depth limit) (#21858) New diagnostics for unused range suppressions (#21783) [ty] Use default settings in completion tests [ty] Infer type variables within generic unions (#21862) [ty] Fix overload filtering to prefer more "precise" match (#21859) [ty] Stabilize auto-import [ty] Fix reveal-type E2E test (#21865) [ty] Use concise message for LSP clients not supporting related diagnostic information (#21850) Include more details in Tokens 'offset is inside token' panic message (#21860) apply range suppressions to filter diagnostics (#21623) [ty] followup: add-import action for `reveal_type` too (#21668) [ty] Enrich function argument auto-complete suggestions with annotated types [ty] Add autocomplete suggestions for function arguments [`flake8-bugbear`] Accept immutable slice default arguments (`B008`) (#21823) ...
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Closes issue #21565
Summary
As pointed out in the issue, slices are currently flagged by B008 but this behavior is incorrect because slices are immutable.
Test Plan
Added a test case in the "B006_B008.py" fixture. Sorry for the diff in the snapshots, the only thing that changes in those flies is the line numbers, though.
You can also test this manually with this file: