Added support for bidirectional type inference for assignment stateme…

[erictraut]

…nts that are assigning to an index expression that is subscripted by a slice. This addresses #9564.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

sympy (https://github.com/sympy/sympy)
-   /tmp/mypy_primer/projects/sympy/sympy/integrals/intpoly.py:748:17 - error: Argument of type "list[Unknown]" cannot be assigned to parameter "value" of type "None" in function "__setitem__"
+   /tmp/mypy_primer/projects/sympy/sympy/integrals/intpoly.py:748:17 - error: Argument of type "list[Any | int]" cannot be assigned to parameter "value" of type "None" in function "__setitem__"
-     "list[Unknown]" is not assignable to "None" (reportArgumentType)
+     "list[Any | int]" is not assignable to "None" (reportArgumentType)
-   /tmp/mypy_primer/projects/sympy/sympy/physics/control/lti.py:2066:23 - error: Operator "-" not supported for type "Basic" (reportOperatorIssue)
+   /tmp/mypy_primer/projects/sympy/sympy/physics/control/lti.py:2066:23 - error: Operator "-" not supported for type "Basic" when expected type is "Basic" (reportOperatorIssue)
-     Operator "**" not supported for types "Basic" and "Basic"
+     Operator "**" not supported for types "Basic" and "Basic" when expected type is "Expr"
-     Operator "**" not supported for types "Dict" and "Basic" (reportOperatorIssue)
+     Operator "**" not supported for types "Dict" and "Basic" when expected type is "Expr" (reportOperatorIssue)
-   /tmp/mypy_primer/projects/sympy/sympy/tensor/tensor.py:3858:27 - error: Operator "-" not supported for type "Basic" (reportOperatorIssue)
+   /tmp/mypy_primer/projects/sympy/sympy/tensor/tensor.py:3858:27 - error: Operator "-" not supported for type "Basic" when expected type is "Basic" (reportOperatorIssue)

core (https://github.com/home-assistant/core)
+   /tmp/mypy_primer/projects/core/homeassistant/loader.py:270:5 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/loader.py:270:5 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, ModuleType | ComponentProtocol]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, ModuleType | ComponentProtocol]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "ModuleType | ComponentProtocol"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/loader.py:271:5 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/loader.py:271:5 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, Integration | Future[None]]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, Integration | Future[None]]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "Integration | Future[None]"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/loader.py:272:5 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/loader.py:272:5 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, bool]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, bool]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "bool"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/setup.py:108:18 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/setup.py:108:18 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, str | None]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, str | None]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "str | None"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/setup.py:110:5 - error: Argument of type "object* | str | None" cannot be assigned to parameter "value" of type "str | None" in function "__setitem__"
+     Type "object* | str | None" is not assignable to type "str | None"
+       Type "object*" is not assignable to type "str | None"
+         "object*" is not assignable to "str"
+         "object*" is not assignable to "None" (reportArgumentType)
+ /tmp/mypy_primer/projects/core/homeassistant/components/arwn/sensor.py
+   /tmp/mypy_primer/projects/core/homeassistant/components/arwn/sensor.py:147:17 - error: Argument of type "() -> (str | UndefinedType | None)" cannot be assigned to parameter "key" of type "str" in function "__setitem__"
+     "function" is not assignable to "str" (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/components/arwn/sensor.py:158:17 - error: Argument of type "() -> (str | UndefinedType | None)" cannot be assigned to parameter "key" of type "str" in function "__getitem__"
+     "function" is not assignable to "str" (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/components/arwn/sensor.py:158:36 - error: Cannot access attribute "set_event" for class "object*"
+     Attribute "set_event" is unknown (reportAttributeAccessIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/components/assist_satellite/__init__.py:66:5 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/components/assist_satellite/__init__.py:66:5 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, Event]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, Event]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "Event"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/components/profiler/__init__.py:120:9 - error: Object of type "object*" is not callable
+     Attribute "__call__" is unknown (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/components/profiler/__init__.py:163:9 - error: Object of type "object*" is not callable
+     Attribute "__call__" is unknown (reportCallIssue)
+ /tmp/mypy_primer/projects/core/homeassistant/components/stt/legacy.py
+   /tmp/mypy_primer/projects/core/homeassistant/components/stt/legacy.py:59:17 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/components/stt/legacy.py:59:17 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, Provider]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, Provider]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "Provider"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/components/trace/__init__.py:50:5 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/components/trace/__init__.py:50:5 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "TraceData"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, LimitedSizeDict[str, BaseTrace]]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "LimitedSizeDict[str, BaseTrace]"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+ /tmp/mypy_primer/projects/core/homeassistant/components/websocket_api/__init__.py
+   /tmp/mypy_primer/projects/core/homeassistant/components/websocket_api/__init__.py:67:5 - error: Argument of type "Any | str | WebSocketCommandHandler" cannot be assigned to parameter "key" of type "str" in function "__setitem__"
+     Type "Any | str | WebSocketCommandHandler" is not assignable to type "str"
+       "function" is not assignable to "str" (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/helpers/llm.py:631:32 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/helpers/llm.py:631:32 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, tuple[str | None, Unknown]]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, tuple[str | None, Unknown]]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "tuple[str | None, Unknown]"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/helpers/llm.py:654:20 - error: Type "_S@__setitem__ | tuple[str | None, Unknown]" is not assignable to return type "tuple[str | None, Unknown]"
+     Type "object* | tuple[str | None, Unknown]" is not assignable to type "tuple[str | None, Unknown]"
+       "object*" is not assignable to "tuple[str | None, Unknown]" (reportReturnType)
+   /tmp/mypy_primer/projects/core/homeassistant/helpers/script.py:1433:13 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)
+   /tmp/mypy_primer/projects/core/homeassistant/helpers/script.py:1433:13 - error: Argument of type "dict[str, _S@__setitem__]" cannot be assigned to parameter "value" of type "_S@__setitem__" in function "__setitem__"
+     Type "dict[str, _S@__setitem__]" is not assignable to type "dict[str, dict[str, set[str]]]"
+       "dict[str, _S@__setitem__]" is not assignable to "dict[str, dict[str, set[str]]]"
+         Type parameter "_VT@dict" is invariant, but "_S@__setitem__" is not the same as "dict[str, set[str]]"
+         Consider switching from "dict" to "Mapping" which is covariant in the value type (reportArgumentType)
+   /tmp/mypy_primer/projects/core/homeassistant/helpers/script.py:2059:5 - error: No overloads for "__setitem__" match the provided arguments (reportCallIssue)

... (truncated 36 lines) ...

pycryptodome (https://github.com/Legrandin/pycryptodome)
-   /tmp/mypy_primer/projects/pycryptodome/lib/Crypto/SelfTest/Hash/test_TupleHash.py:262:13 - error: Argument of type "list[Unknown]" cannot be assigned to parameter "value" of type "None" in function "__setitem__"
+   /tmp/mypy_primer/projects/pycryptodome/lib/Crypto/SelfTest/Hash/test_TupleHash.py:262:13 - error: Argument of type "list[Any]" cannot be assigned to parameter "value" of type "None" in function "__setitem__"
-     "list[Unknown]" is not assignable to "None" (reportArgumentType)
+     "list[Any]" is not assignable to "None" (reportArgumentType)