WIP: use annotated parameters as type context

crates/ty_python_semantic/resources/mdtest/call/overloads.md

@@ -1682,3 +1682,57 @@ def _(arg: tuple[A | B, Any]):
     reveal_type(f(arg))  # revealed: Unknown
     reveal_type(f(*(arg,)))  # revealed: Unknown
 ```
+
+## Bi-directional Type Inference
+
+Type inference accounts for the type of each overload.
+
+```py
+from typing import TypedDict, overload
+
+class T(TypedDict):
+  x: int
+
+@overload
+def f(a: list[T], b: int):
+  ...
+
+@overload
+def f(a: list[dict[str, int]], b: str):
+  ...
+
+def f(a: list[dict[str, int]] | list[T], b: int | str):
+  ...
+
+def int_or_str() -> int | str:
+  return 1
+
+f([{ "x": 1 }], int_or_str())
+
+# error: [missing-typed-dict-key] "Missing required key 'x' in TypedDict `T` constructor"
+# error: [invalid-key] "Invalid key access on TypedDict `T`: Unknown key "y""
+f([{ "y": 1 }], int_or_str())
+```
+
+Non-matching overloads do not produce errors:
+
+```py
+from typing import TypedDict, overload
+
+class T(TypedDict):
+  x: int
+
+@overload
+def f(a: T, b: int):
+  ...
+
+@overload
+def f(a: dict[str, int], b: str):
+  ...
+
+def f(a: T | dict[str, int], b: int | str):
+  ...
+
+# TODO
+f({ "y": 1 }, "a")
+```

crates/ty_python_semantic/resources/mdtest/typed_dict.md

@@ -152,7 +152,7 @@ Person(name="Alice")
 # error: [missing-typed-dict-key] "Missing required key 'age' in TypedDict `Person` constructor"
 Person({"name": "Alice"})
 
-# TODO: this should be an error, similar to the above
+# error: [missing-typed-dict-key] "Missing required key 'age' in TypedDict `Person` constructor"
 accepts_person({"name": "Alice"})
 # TODO: this should be an error, similar to the above
 house.owner = {"name": "Alice"}
@@ -171,7 +171,7 @@ Person(name=None, age=30)
 # error: [invalid-argument-type] "Invalid argument to key "name" with declared type `str` on TypedDict `Person`: value of type `None`"
 Person({"name": None, "age": 30})
 
-# TODO: this should be an error, similar to the above
+# error: [invalid-argument-type] "Invalid argument to key "name" with declared type `str` on TypedDict `Person`: value of type `None`"
 accepts_person({"name": None, "age": 30})
 # TODO: this should be an error, similar to the above
 house.owner = {"name": None, "age": 30}
@@ -190,7 +190,7 @@ Person(name="Alice", age=30, extra=True)
 # error: [invalid-key] "Invalid key access on TypedDict `Person`: Unknown key "extra""
 Person({"name": "Alice", "age": 30, "extra": True})
 
-# TODO: this should be an error
+# error: [invalid-key] "Invalid key access on TypedDict `Person`: Unknown key "extra""
 accepts_person({"name": "Alice", "age": 30, "extra": True})
 # TODO: this should be an error
 house.owner = {"name": "Alice", "age": 30, "extra": True}