ASYNC250 false positive for input call wrapped into lambda

[RomanValov]

Summary

Hello,

with the recent updates ruff started to complain on following snippet of code:

import asyncio


async def main() -> None:
    input("sync")
    await asyncio.to_thread(lambda: input("async"))


if __name__ == '__main__':
    asyncio.run(main())

$ ruff check --select=ASYNC250 async.py
ASYNC250 Blocking call to `input()` in async context
 --> async.py:6:5
  |
5 | async def main() -> None:
6 |     input("sync")
  |     ^^^^^
7 |     await asyncio.to_thread(lambda: input("async"))
  |

ASYNC250 Blocking call to `input()` in async context
 --> async.py:7:37
  |
5 | async def main() -> None:
6 |     input("sync")
7 |     await asyncio.to_thread(lambda: input("async"))
  |                                     ^^^^^
  |

Found 2 errors.

for comparison flake8-async passes "async" invocation:

$ flake8 --enable=ASYNC250 async.py
async.py:6:5: ASYNC250 Blocking sync call `input()` in async function. Wrap in `asyncio.loop.run_in_executor`.

Version

ruff 0.15.1

[ntBre]

Thanks for the report! Looks like the rule uses this function:

ruff/crates/ruff_python_semantic/src/model.rs

Lines 1595 to 1603 in 1425c18

	/// Return `true` if the model is in an async context.
	pub fn in_async_context(&self) -> bool {
	for scope in self.current_scopes() {
	if let ScopeKind::Function(ast::StmtFunctionDef { is_async, .. }) = scope.kind {
	return *is_async;
	}
	}
	false
	}

which I think maybe should return false if it encounters a lambda, more like the version on Checker:

ruff/crates/ruff_linter/src/checkers/ast/mod.rs

Lines 799 to 811 in 1425c18

	fn in_async_context(&self) -> bool {
	for scope in self.semantic.current_scopes() {
	match scope.kind {
	ScopeKind::Class(_) | ScopeKind::Lambda(_) => return false,
	ScopeKind::Function(ast::StmtFunctionDef { is_async, .. }) => return *is_async,
	ScopeKind::Generator { .. }
	| ScopeKind::Module
	| ScopeKind::Type
	| ScopeKind::DunderClassCell => {}
	}
	}
	false
	}

cc @amyreese