mirror of https://github.com/astral-sh/ruff
957320c0f1
## Summary This PR adds a new lint, `invalid-await`, for all sorts of reasons why an object may not be `await`able, as discussed in astral-sh/ty#919. Precisely, `__await__` is guarded against being missing, possibly unbound, or improperly defined (expects additional arguments or doesn't return an iterator). Of course, diagnostics need to be fine-tuned. If `__await__` cannot be called with no extra arguments, it indicates an error (or a quirk?) in the method signature, not at the call site. Without any doubt, such an object is not `Awaitable`, but I feel like talking about arguments for an *implicit* call is a bit leaky. I didn't reference any actual diagnostic messages in the lint definition, because I want to hear feedback first. Also, there's no mention of the actual required method signature for `__await__` anywhere in the docs. The only reference I had is the `typing` stub. I basically ended up linking `[Awaitable]` to ["must implement `__await__`"](https://docs.python.org/3/library/collections.abc.html#collections.abc.Awaitable), which is insufficient on its own. ## Test Plan The following code was tested: ```python import asyncio import typing class Awaitable: def __await__(self) -> typing.Generator[typing.Any, None, int]: yield None return 5 class NoDunderMethod: pass class InvalidAwaitArgs: def __await__(self, value: int) -> int: return value class InvalidAwaitReturn: def __await__(self) -> int: return 5 class InvalidAwaitReturnImplicit: def __await__(self): pass async def main() -> None: result = await Awaitable() # valid result = await NoDunderMethod() # `__await__` is missing result = await InvalidAwaitReturn() # `__await__` returns `int`, which is not a valid iterator result = await InvalidAwaitArgs() # `__await__` expects additional arguments and cannot be called implicitly result = await InvalidAwaitReturnImplicit() # `__await__` returns `Unknown`, which is not a valid iterator asyncio.run(main()) ``` --------- Co-authored-by: Carl Meyer <carl@astral.sh> |
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| .. | ||
| ruff | ||
| ruff_annotate_snippets | ||
| ruff_benchmark | ||
| ruff_cache | ||
| ruff_db | ||
| ruff_dev | ||
| ruff_diagnostics | ||
| ruff_formatter | ||
| ruff_graph | ||
| ruff_index | ||
| ruff_linter | ||
| ruff_macros | ||
| ruff_memory_usage | ||
| ruff_notebook | ||
| ruff_options_metadata | ||
| ruff_python_ast | ||
| ruff_python_ast_integration_tests | ||
| ruff_python_codegen | ||
| ruff_python_formatter | ||
| ruff_python_index | ||
| ruff_python_literal | ||
| ruff_python_parser | ||
| ruff_python_semantic | ||
| ruff_python_stdlib | ||
| ruff_python_trivia | ||
| ruff_python_trivia_integration_tests | ||
| ruff_server | ||
| ruff_source_file | ||
| ruff_text_size | ||
| ruff_wasm | ||
| ruff_workspace | ||
| ty | ||
| ty_combine | ||
| ty_ide | ||
| ty_project | ||
| ty_python_semantic | ||
| ty_server | ||
| ty_static | ||
| ty_test | ||
| ty_vendored | ||
| ty_wasm | ||