[ty] implement TypedDict structural assignment (#21467)

Closes astral-sh/ty#1387.

Author: oconnor663

crates/ty_python_semantic/resources/mdtest/assignment/annotations.md

@@ -482,17 +482,14 @@ class TD2(TypedDict):
     x: str
 
 def f(self, dt: dict[str, Any], key: str):
-    # TODO: This should not error once typed dict assignability is implemented.
-    # error: [invalid-assignment]
     x1: TD = dt.get(key, {})
-    reveal_type(x1)  # revealed: TD
+    reveal_type(x1)  # revealed: Any
 
     x2: TD = dt.get(key, {"x": 0})
     reveal_type(x2)  # revealed: Any
 
     x3: TD | None = dt.get(key, {})
-    # TODO: This should reveal `Any` once typed dict assignability is implemented.
-    reveal_type(x3)  # revealed: Any | None
+    reveal_type(x3)  # revealed: Any
 
     x4: TD | None = dt.get(key, {"x": 0})
     reveal_type(x4)  # revealed: Any

crates/ty_python_semantic/resources/mdtest/diagnostics/same_names.md

@@ -265,7 +265,7 @@ import dict_a
 import dict_b
 
 def _(b_person: dict_b.Person):
-    # TODO should be error: [invalid-assignment] "Object of type `dict_b.Person` is not assignable to `dict_a.Person`"
+    # error: [invalid-assignment] "Object of type `dict_b.Person` is not assignable to `dict_a.Person`"
     person_var: dict_a.Person = b_person
 ```
 

crates/ty_python_semantic/resources/mdtest/snapshots/assignment_diagnosti…_-_Subscript_assignment…_-_Unknown_key_for_all_…_(1c685d9d10678263).snap renamed to crates/ty_python_semantic/resources/mdtest/snapshots/assignment_diagnosti…_-_Subscript_assignment…_-_Unknown_key_for_all_…_(8a0f0e8ceccc51b2).snap

@@ -3,7 +3,7 @@ source: crates/ty_test/src/lib.rs
 expression: snapshot
 ---
 ---
-mdtest name: assignment_diagnostics.md - Subscript assignment diagnostics - Unknown key for all elemens of a union
+mdtest name: assignment_diagnostics.md - Subscript assignment diagnostics - Unknown key for all elements of a union
 mdtest path: crates/ty_python_semantic/resources/mdtest/subscript/assignment_diagnostics.md
 ---
 
@@ -16,26 +16,27 @@ mdtest path: crates/ty_python_semantic/resources/mdtest/subscript/assignment_dia
  2 | 
  3 | class Person(TypedDict):
  4 |     name: str
- 5 | 
- 6 | class Animal(TypedDict):
- 7 |     name: str
- 8 |     legs: int
- 9 | 
-10 | def _(being: Person | Animal) -> None:
-11 |     # error: [invalid-key]
+ 5 |     phone_number: str
+ 6 | 
+ 7 | class Animal(TypedDict):
+ 8 |     name: str
+ 9 |     legs: int
+10 | 
+11 | def _(being: Person | Animal) -> None:
 12 |     # error: [invalid-key]
-13 |     being["surname"] = "unknown"
+13 |     # error: [invalid-key]
+14 |     being["surname"] = "unknown"
 ```
 
 # Diagnostics
 
 ```
 error[invalid-key]: Unknown key "surname" for TypedDict `Person`
-  --> src/mdtest_snippet.py:13:5
+  --> src/mdtest_snippet.py:14:5
    |
-11 |     # error: [invalid-key]
 12 |     # error: [invalid-key]
-13 |     being["surname"] = "unknown"
+13 |     # error: [invalid-key]
+14 |     being["surname"] = "unknown"
    |     ----- ^^^^^^^^^ Did you mean "name"?
    |     |
    |     TypedDict `Person` in union type `Person | Animal`
@@ -46,11 +47,11 @@ info: rule `invalid-key` is enabled by default
 
 ```
 error[invalid-key]: Unknown key "surname" for TypedDict `Animal`
-  --> src/mdtest_snippet.py:13:5
+  --> src/mdtest_snippet.py:14:5
    |
-11 |     # error: [invalid-key]
 12 |     # error: [invalid-key]
-13 |     being["surname"] = "unknown"
+13 |     # error: [invalid-key]
+14 |     being["surname"] = "unknown"
    |     ----- ^^^^^^^^^ Did you mean "name"?
    |     |
    |     TypedDict `Animal` in union type `Person | Animal`

crates/ty_python_semantic/resources/mdtest/snapshots/assignment_diagnosti…_-_Subscript_assignment…_-_Unknown_key_for_one_…_(b515711c0a451a86).snap

@@ -16,23 +16,24 @@ mdtest path: crates/ty_python_semantic/resources/mdtest/subscript/assignment_dia
  2 | 
  3 | class Person(TypedDict):
  4 |     name: str
- 5 | 
- 6 | class Animal(TypedDict):
- 7 |     name: str
- 8 |     legs: int
- 9 | 
-10 | def _(being: Person | Animal) -> None:
-11 |     being["legs"] = 4  # error: [invalid-key]
+ 5 |     phone_number: str
+ 6 | 
+ 7 | class Animal(TypedDict):
+ 8 |     name: str
+ 9 |     legs: int
+10 | 
+11 | def _(being: Person | Animal) -> None:
+12 |     being["legs"] = 4  # error: [invalid-key]
 ```
 
 # Diagnostics
 
 ```
 error[invalid-key]: Unknown key "legs" for TypedDict `Person`
-  --> src/mdtest_snippet.py:11:5
+  --> src/mdtest_snippet.py:12:5
    |
-10 | def _(being: Person | Animal) -> None:
-11 |     being["legs"] = 4  # error: [invalid-key]
+11 | def _(being: Person | Animal) -> None:
+12 |     being["legs"] = 4  # error: [invalid-key]
    |     ----- ^^^^^^ Unknown key "legs"
    |     |
    |     TypedDict `Person` in union type `Person | Animal`

crates/ty_python_semantic/resources/mdtest/subscript/assignment_diagnostics.md

@@ -95,6 +95,7 @@ from typing import TypedDict
 
 class Person(TypedDict):
     name: str
+    phone_number: str
 
 class Animal(TypedDict):
     name: str
@@ -104,13 +105,14 @@ def _(being: Person | Animal) -> None:
     being["legs"] = 4  # error: [invalid-key]
 ```
 
-## Unknown key for all elemens of a union
+## Unknown key for all elements of a union
 
 ```py
 from typing import TypedDict
 
 class Person(TypedDict):
     name: str
+    phone_number: str
 
 class Animal(TypedDict):
     name: str