David Peter 4ecf1d205a [ty] Support async/await, async with and yield from (#19595) ... ## Summary - Add support for the return types of `async` functions - Add type inference for `await` expressions - Add support for `async with` / async context managers - Add support for `yield from` expressions This PR is generally lacking proper error handling in some cases (e.g. illegal `__await__` attributes). I'm planning to work on this in a follow-up. part of https://github.com/astral-sh/ty/issues/151 closes https://github.com/astral-sh/ty/issues/736 ## Ecosystem There are a lot of true positives on `prefect` which look similar to: ```diff prefect (https://github.com/PrefectHQ/prefect) + src/integrations/prefect-aws/tests/workers/test_ecs_worker.py:406:12: error[unresolved-attribute] Type `str` has no attribute `status_code` ``` This is due to a wrong return type annotation [here](e926b8c4c1/src/integrations/prefect-aws/tests/workers/test_ecs_worker.py (L355-L391)). ```diff mitmproxy (https://github.com/mitmproxy/mitmproxy) + test/mitmproxy/addons/test_clientplayback.py:18:1: error[invalid-argument-type] Argument to function `asynccontextmanager` is incorrect: Expected `(...) -> AsyncIterator[Unknown]`, found `def tcp_server(handle_conn, **server_args) -> Unknown | tuple[str, int]` ``` [This](a4d794c59a/test/mitmproxy/addons/test_clientplayback.py (L18-L19)) is a true positive. That function should return `AsyncIterator[Address]`, not `Address`. I looked through almost all of the other new diagnostics and they all look like known problems or true positives. ## Typing conformance The typing conformance diff looks good. ## Test Plan New Markdown tests		2025-07-30 11:51:21 +02:00
..
annotation.md	ty_python_semantic: add union type context to function call type errors	2025-05-09 13:40:51 -04:00
builtins.md	[ty] Reachability analysis for isinstance(…) branches (#19503)	2025-07-23 13:06:30 +02:00
callable_instance.md	ty_python_semantic: add union type context to function call type errors	2025-05-09 13:40:51 -04:00
constructor.md	[ty] Rename call-possibly-unbound-method to possibly-unbound-implicit-call (#18017)	2025-05-22 15:25:51 +00:00
dunder.md	[ty] Allow declared-only class-level attributes to be accessed on the class (#19071)	2025-07-02 18:03:56 +02:00
dunder_import.md	[ty] Add special-cased inference for __import__(name) and importlib.import_module(name) (#19008)	2025-06-29 11:49:23 +01:00
function.md	[ty] Support async/await, async with and yield from (#19595)	2025-07-30 11:51:21 +02:00
getattr_static.md	[ty] eliminate is_fully_static (#18799)	2025-06-24 18:02:05 -07:00
invalid_syntax.md	ty_python_semantic: add union type context to function call type errors	2025-05-09 13:40:51 -04:00
methods.md	[ty] Consistent use of American english (in rules) (#19488)	2025-07-22 16:10:38 +02:00
never.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
overloads.md	[ty] Splat variadic arguments into parameter list (#18996)	2025-07-22 14:33:08 -04:00
replace.md	[ty] synthesize __replace__ for dataclasses (>=3.13) (#19545)	2025-07-29 17:32:01 +02:00
str_startswith.md	Rename Red Knot (#17820)	2025-05-03 19:49:15 +02:00
subclass_of.md	[ty] Include synthesized arguments in displayed counts for too-many-positional-arguments (#18098)	2025-05-14 22:51:23 -04:00
union.md	[ty] eliminate is_fully_static (#18799)	2025-06-24 18:02:05 -07:00