[ty] Infer type variables within generic unions #21862
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Diagnostic diff on typing conformance testsNo changes detected when running ty on typing conformance tests ✅ |
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| Lint rule | Added | Removed | Changed |
|---|---|---|---|
invalid-argument-type |
7 | 128 | 57 |
unresolved-attribute |
0 | 21 | 1 |
possibly-missing-attribute |
0 | 0 | 14 |
not-iterable |
0 | 0 | 10 |
type-assertion-failure |
1 | 4 | 4 |
invalid-assignment |
2 | 0 | 3 |
invalid-return-type |
1 | 0 | 1 |
unsupported-operator |
0 | 0 | 2 |
invalid-context-manager |
0 | 0 | 1 |
non-subscriptable |
0 | 0 | 1 |
unused-ignore-comment |
1 | 0 | 0 |
| Total | 12 | 153 | 94 |
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This approach looks good to me. That match arm is a big pile of heuristics already, so if there are corner cases that this doesn't handle, I think it's fine to be generous about marking things as TODO. This seems like a clear win as-is in how it handles the P[T] | Q[T] case.
crates/ty_python_semantic/resources/mdtest/generics/pep695/functions.md
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…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) ...
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…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) ...
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…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) ...
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* 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) ...
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Summary
This PR allows our generics solver to find a solution for
Tin cases like the following:closes astral-sh/ty#1772
closes astral-sh/ty#1314
Ecosystem
The impact here looks very good!
It took me a long time to figure this out, but the new diagnostics on bokeh are actually true positives. I should have tested with another type-checker immediately, I guess. All other type checkers also emit errors on these
__init__calls. MRE here (no error on main, diagnostic on this branch)A lot of false positives on home-assistant go away for calls to functions like
async_listenwhich take aevent_type: EventType[_DataT] | strparameter. We can now solve for_DataThere, which was previously falling back to its default value, and then caused problems because it was used as an argument to an invariant generic class.Test Plan
New Markdown tests