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
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assert.md
attribute.md	Update class literal display to use <class 'Foo'> style (#17889)	2025-05-06 20:11:25 -04:00
boolean.md	[ty] Make tuple subclass constructors sound (#19469)	2025-07-21 21:25:11 +00:00
if.md
lambda.md	[ty] Treat lambda functions as instances of types.FunctionType (#18431)	2025-06-02 16:46:26 +01:00
len.md	[ty] Extend tuple __len__ and __bool__ special casing to also cover tuple subclasses (#19289)	2025-07-21 12:50:46 +00:00
yield_and_yield_from.md	[ty] Support async/await, async with and yield from (#19595)	2025-07-30 11:51:21 +02:00