ruff/crates
David Peter a1edb69ea5
[ty] Enum literal types (#19328)
## Summary

Add a new `Type::EnumLiteral(…)` variant and infer this type for member
accesses on enums.

**Example**: No more `@Todo` types here:
```py
from enum import Enum

class Answer(Enum):
    YES = 1
    NO = 2

    def is_yes(self) -> bool:
        return self == Answer.YES

reveal_type(Answer.YES)  # revealed: Literal[Answer.YES]
reveal_type(Answer.YES == Answer.NO)  # revealed: Literal[False]
reveal_type(Answer.YES.is_yes())  # revealed: bool
```

## Test Plan

* Many new Markdown tests for the new type variant
* Added enum literal types to property tests, ran property tests

## Ecosystem analysis

Summary:

Lots of false positives removed. All of the new diagnostics are
either new true positives (the majority) or known problems. Click for
detailed analysis</summary>

Details:

```diff
AutoSplit (https://github.com/Toufool/AutoSplit)
+ error[call-non-callable] src/capture_method/__init__.py:137:9: Method `__getitem__` of type `bound method CaptureMethodDict.__getitem__(key: Never, /) -> type[CaptureMethodBase]` is not callable on object of type `CaptureMethodDict`
+ error[call-non-callable] src/capture_method/__init__.py:147:9: Method `__getitem__` of type `bound method CaptureMethodDict.__getitem__(key: Never, /) -> type[CaptureMethodBase]` is not callable on object of type `CaptureMethodDict`
+ error[call-non-callable] src/capture_method/__init__.py:148:1: Method `__getitem__` of type `bound method CaptureMethodDict.__getitem__(key: Never, /) -> type[CaptureMethodBase]` is not callable on object of type `CaptureMethodDict`
```

New true positives. That `__getitem__` method is apparently annotated
with `Never` to prevent developers from using it.


```diff
dd-trace-py (https://github.com/DataDog/dd-trace-py)
+ error[invalid-assignment] ddtrace/vendor/psutil/_common.py:29:5: Object of type `None` is not assignable to `Literal[AddressFamily.AF_INET6]`
+ error[invalid-assignment] ddtrace/vendor/psutil/_common.py:33:5: Object of type `None` is not assignable to `Literal[AddressFamily.AF_UNIX]`
```

Arguably true positives:
e0a772c28b/ddtrace/vendor/psutil/_common.py (L29)

```diff
ignite (https://github.com/pytorch/ignite)
+ error[invalid-argument-type] tests/ignite/engine/test_custom_events.py:190:34: Argument to bound method `__call__` is incorrect: Expected `((...) -> Unknown) | None`, found `Literal["123"]`
+ error[invalid-argument-type] tests/ignite/engine/test_custom_events.py:220:37: Argument to function `default_event_filter` is incorrect: Expected `Engine`, found `None`
+ error[invalid-argument-type] tests/ignite/engine/test_custom_events.py:220:43: Argument to function `default_event_filter` is incorrect: Expected `int`, found `None`
+ error[call-non-callable] tests/ignite/engine/test_custom_events.py:561:9: Object of type `CustomEvents` is not callable
+ error[invalid-argument-type] tests/ignite/metrics/test_frequency.py:50:38: Argument to bound method `attach` is incorrect: Expected `Events`, found `CallableEventWithFilter`
```

All true positives. Some of them are inside `pytest.raises(TypeError,
…)` blocks 🙃

```diff
meson (https://github.com/mesonbuild/meson)
+ error[invalid-argument-type] unittests/internaltests.py:243:51: Argument to bound method `__init__` is incorrect: Expected `bool`, found `Literal[MachineChoice.HOST]`
+ error[invalid-argument-type] unittests/internaltests.py:271:51: Argument to bound method `__init__` is incorrect: Expected `bool`, found `Literal[MachineChoice.HOST]`
```

New true positives. Enum literals can not be assigned to `bool`, even if
their value types are `0` and `1`.

```diff
poetry (https://github.com/python-poetry/poetry)
+ error[invalid-assignment] src/poetry/console/exceptions.py:101:5: Object of type `Literal[""]` is not assignable to `InitVar[str]`
```

New false positive, missing support for `InitVar`.

```diff
prefect (https://github.com/PrefectHQ/prefect)
+ error[invalid-argument-type] src/integrations/prefect-dask/tests/test_task_runners.py:193:17: Argument is incorrect: Expected `StateType`, found `Literal[StateType.COMPLETED]`
```

This is confusing. There are two definitions
([one](74d8cd93ee/src/prefect/client/schemas/objects.py (L89-L100)),
[two](https://github.com/PrefectHQ/prefect/blob/main/src/prefect/server/schemas/states.py#L40))
of the `StateType` enum. Here, we're trying to assign one to the other.
I don't think that should be allowed, so this is a true positive (?).

```diff
python-htmlgen (https://github.com/srittau/python-htmlgen)
+ error[invalid-assignment] test_htmlgen/form.py:51:9: Object of type `str` is not assignable to attribute `autocomplete` of type `Autocomplete | None`
+ error[invalid-assignment] test_htmlgen/video.py:38:9: Object of type `str` is not assignable to attribute `preload` of type `Preload | None`
```

True positives. [The stubs are
wrong](01e3b911ac/htmlgen/form.pyi (L8-L10)).
These should not contain type annotations, but rather just `OFF = ...`.

```diff
rotki (https://github.com/rotki/rotki)
+ error[invalid-argument-type] rotkehlchen/tests/unit/test_serialization.py:62:30: Argument to bound method `deserialize` is incorrect: Expected `str`, found `Literal[15]`
```

New true positive.

```diff
vision (https://github.com/pytorch/vision)
+ error[unresolved-attribute] test/test_extended_models.py:302:17: Type `type[WeightsEnum]` has no attribute `DEFAULT`
+ error[unresolved-attribute] test/test_extended_models.py:302:58: Type `type[WeightsEnum]` has no attribute `DEFAULT`
```

Also new true positives. No `DEFAULT` member exists on `WeightsEnum`.
2025-07-15 21:31:53 +02:00
..
ruff Move Pylint rendering to ruff_db (#19340) 2025-07-15 10:14:49 -04:00
ruff_annotate_snippets Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_benchmark [ty] Enum literal types (#19328) 2025-07-15 21:31:53 +02:00
ruff_cache
ruff_db Move Pylint rendering to ruff_db (#19340) 2025-07-15 10:14:49 -04:00
ruff_dev Auto-generate environment variable references for ty (#19205) 2025-07-08 10:48:31 -04:00
ruff_diagnostics Combine OldDiagnostic and Diagnostic (#19053) 2025-07-03 13:01:09 -04:00
ruff_formatter
ruff_graph Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_index Update Rust toolchain to 1.88 and MSRV to 1.86 (#19011) 2025-06-28 20:24:00 +02:00
ruff_linter [pycodestyle] Handle brace escapes for t-strings in logical lines (#19358) 2025-07-15 14:48:48 +00:00
ruff_macros [ty] Merge ty_macros into ruff_macros (#19229) 2025-07-09 11:28:21 +00:00
ruff_notebook
ruff_options_metadata
ruff_python_ast [ty] Use an interval map for scopes by expression (#19025) 2025-07-14 13:50:58 +02:00
ruff_python_ast_integration_tests
ruff_python_codegen Fix f-string interpolation escaping (#18882) 2025-06-25 10:04:15 +02:00
ruff_python_formatter Update pre-commit dependencies (#19162) 2025-07-07 04:07:44 +00:00
ruff_python_index
ruff_python_literal
ruff_python_parser [ty] add support for nonlocal statements 2025-07-11 09:44:54 -07:00
ruff_python_semantic [flake8-return] Fix false-positive for variables used inside nested functions in RET504 (#18433) 2025-07-10 16:10:22 -04:00
ruff_python_stdlib
ruff_python_trivia
ruff_python_trivia_integration_tests
ruff_server Render Azure, JSON, and JSON lines output with the new diagnostics (#19133) 2025-07-11 15:04:46 -04:00
ruff_source_file Move Pylint rendering to ruff_db (#19340) 2025-07-15 10:14:49 -04:00
ruff_text_size [ty] Add environment variable to dump Salsa memory usage stats (#18928) 2025-06-26 21:27:51 +00:00
ruff_wasm Bump 0.12.3 (#19279) 2025-07-11 09:07:50 -04:00
ruff_workspace Fix description of the format.skip-magic-trailing-comma example (#19095) 2025-07-03 10:39:59 -04:00
ty [ty] Allow -qq for silent output mode (#19366) 2025-07-15 17:08:19 +00:00
ty_ide [ty] Enum literal types (#19328) 2025-07-15 21:31:53 +02:00
ty_project [ty] Use python version and path from Python extension (#19012) 2025-07-14 09:47:27 +00:00
ty_python_semantic [ty] Enum literal types (#19328) 2025-07-15 21:31:53 +02:00
ty_server [ty] Remove ConnectionInitializer (#19353) 2025-07-15 17:02:44 +05:30
ty_static [ty] Merge ty_macros into ruff_macros (#19229) 2025-07-09 11:28:21 +00:00
ty_test [ty] Make check_file a salsa query (#19255) 2025-07-10 18:46:56 +05:30
ty_vendored [ty] Sync vendored typeshed stubs (#19368) 2025-07-15 18:14:46 +00:00
ty_wasm [ty] Fix server version (#19284) 2025-07-14 09:06:34 +02:00