Constrain memoryview type var to allowed types

[srittau]

No description provided.

[JelleZijlstra]

I haven't fully thought this through but #13519 partially made me think that making memoryview generic with a default was a mistake. memoryview now means memoryview[int], so if you have a memoryview[bytes] you can't pass it to a function that wants a plain memoryview. But usually that's wrong; lots of memoryview functionality doesn't depend on the type parameter and lots of functions will work with any kind of memoryview.

[srittau]

I was thinking about that, but I think changing the default to Any might be a better solution. That keeps the flexibility of restricting memoryviews while by default any memoryview is accepted.

[github-actions]

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

trio (https://github.com/python-trio/trio)
+ src/trio/_abc.py:331: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_highlevel_socket.py:109: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_highlevel_generic.py:94: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_file_io.py:164: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_file_io.py:330: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_ssl.py:737: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_subprocess.py:466: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_subprocess.py:1155: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_subprocess.py:1164: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/testing/_memory_streams.py:44: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/testing/_memory_streams.py:122: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/testing/_memory_streams.py:270: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/testing/_memory_streams.py:499: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/testing/_memory_streams.py:568: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/testing/_check_streams.py:101: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/testing/_check_streams.py:469: error: Explicit "Any" is not allowed  [explicit-any]
+ src/trio/_tests/test_ssl.py:802: error: Explicit "Any" is not allowed  [explicit-any]

hydra-zen (https://github.com/mit-ll-responsible-ai/hydra-zen)
- src/hydra_zen/structured_configs/_implementations.py:1155: error: No overload variant of "builds" of "BuildsFn" matches argument types "type[DataclassInstance]", "dict[str, int | float | Path | DataClass_ | type[DataClass_] | ListConfig | DictConfig | Enum | Sequence[HydraSupportedType] | Mapping[Any, HydraSupportedType] | None]", "bool | None", "Literal['none', 'partial', 'all', 'object'] | None", "DataclassOptions"  [call-overload]
+ src/hydra_zen/structured_configs/_implementations.py:1155: error: No overload variant of "builds" of "BuildsFn" matches argument types "type[DataclassInstance]", "dict[str, int | float | memoryview[Any] | Path | DataClass_ | <6 more items> | None]", "bool | None", "Literal['none', 'partial', 'all', 'object'] | None", "DataclassOptions"  [call-overload]
- src/hydra_zen/structured_configs/_implementations.py:2712: error: Incompatible types in assignment (expression has type "tuple[int | float | Path | DataClass_ | type[DataClass_] | ListConfig | DictConfig | Enum | Sequence[HydraSupportedType] | Mapping[Any, HydraSupportedType] | None, ...]", variable has type "list[Importable | Callable[P, R] | type[Builds[Importable]] | type[BuildsWithSig[Importable, Any]] | type[BuildsWithSig[type[R], P]] | Any]")  [assignment]
+ src/hydra_zen/structured_configs/_implementations.py:2712: error: Incompatible types in assignment (expression has type "tuple[int | float | memoryview[Any] | Path | DataClass_ | <6 more items> | None, ...]", variable has type "list[Importable | Callable[P, R] | type[Builds[Importable]] | type[BuildsWithSig[Importable, Any]] | type[BuildsWithSig[type[R], P]] | Any]")  [assignment]

core (https://github.com/home-assistant/core)
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here

aioredis (https://github.com/aio-libs/aioredis)
- aioredis/connection.py:933: error: Unsupported right operand type for in ("bytes | memoryview[int] | int")  [operator]
+ aioredis/connection.py:933: error: Unsupported right operand type for in ("bytes | memoryview[Any] | int")  [operator]
- aioredis/connection.py:934: error: Item "memoryview[int]" of "bytes | memoryview[int] | int" has no attribute "split"  [union-attr]
+ aioredis/connection.py:934: error: Item "memoryview[Any]" of "bytes | memoryview[Any] | int" has no attribute "split"  [union-attr]
- aioredis/connection.py:934: error: Item "int" of "bytes | memoryview[int] | int" has no attribute "split"  [union-attr]
+ aioredis/connection.py:934: error: Item "int" of "bytes | memoryview[Any] | int" has no attribute "split"  [union-attr]
- aioredis/client.py:4114: error: Incompatible types in assignment (expression has type "dict[bytes | str | memoryview[int], Any | None]", variable has type "dict[bytes | str | memoryview[int], Callable[[dict[str, str]], Awaitable[None]]]")  [assignment]
+ aioredis/client.py:4114: error: Incompatible types in assignment (expression has type "dict[bytes | str | memoryview[Any], Any | None]", variable has type "dict[bytes | str | memoryview[Any], Callable[[dict[str, str]], Awaitable[None]]]")  [assignment]
- aioredis/client.py:4158: error: Argument 1 to "update" of "MutableMapping" has incompatible type "dict[bytes | str | memoryview[int], Any | None]"; expected "SupportsKeysAndGetItem[bytes | str | memoryview[int], Callable[[dict[str, str]], Awaitable[None]]]"  [arg-type]
+ aioredis/client.py:4158: error: Argument 1 to "update" of "MutableMapping" has incompatible type "dict[bytes | str | memoryview[Any], Any | None]"; expected "SupportsKeysAndGetItem[bytes | str | memoryview[Any], Callable[[dict[str, str]], Awaitable[None]]]"  [arg-type]
- aioredis/client.py:4172: error: Incompatible types in assignment (expression has type "dict[bytes | str | memoryview[int], Callable[[dict[str, str]], Awaitable[None]]]", variable has type "dict[Any, Any | None]")  [assignment]
+ aioredis/client.py:4172: error: Incompatible types in assignment (expression has type "dict[bytes | str | memoryview[Any], Callable[[dict[str, str]], Awaitable[None]]]", variable has type "dict[Any, Any | None]")  [assignment]

zulip (https://github.com/zulip/zulip)
- ...typeshed_to_test/stdlib/builtins.pyi:118: note: "SubTest" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:119: note: "SubTest" defined here

ibis (https://github.com/ibis-project/ibis)
- ...typeshed_to_test/stdlib/builtins.pyi:118: note: "Any" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:119: note: "Any" defined here
- ...typeshed_to_test/stdlib/builtins.pyi:118: note: "__init__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:119: note: "__init__" of "object" defined here

prefect (https://github.com/PrefectHQ/prefect)
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here

arviz (https://github.com/arviz-devs/arviz)
- arviz/data/inference_data.py:500: note:     def to_netcdf(self, path: None = ..., mode: Literal['w', 'a'] = ..., format: Literal['NETCDF4', 'NETCDF4_CLASSIC', 'NETCDF3_64BIT', 'NETCDF3_CLASSIC'] | None = ..., group: str | None = ..., engine: Literal['netcdf4', 'scipy', 'h5netcdf'] | None = ..., encoding: Mapping[Any, Mapping[str, Any]] | None = ..., unlimited_dims: Iterable[Hashable] | None = ..., compute: bool = ..., invalid_netcdf: bool = ..., auto_complex: bool | None = ...) -> memoryview[int]
+ arviz/data/inference_data.py:500: note:     def to_netcdf(self, path: None = ..., mode: Literal['w', 'a'] = ..., format: Literal['NETCDF4', 'NETCDF4_CLASSIC', 'NETCDF3_64BIT', 'NETCDF3_CLASSIC'] | None = ..., group: str | None = ..., engine: Literal['netcdf4', 'scipy', 'h5netcdf'] | None = ..., encoding: Mapping[Any, Mapping[str, Any]] | None = ..., unlimited_dims: Iterable[Hashable] | None = ..., compute: bool = ..., invalid_netcdf: bool = ..., auto_complex: bool | None = ...) -> memoryview[Any]

strawberry (https://github.com/strawberry-graphql/strawberry)
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here
- ...typeshed_to_test/stdlib/builtins.pyi:140: note: "__init_subclass__" of "object" defined here
+ ...typeshed_to_test/stdlib/builtins.pyi:141: note: "__init_subclass__" of "object" defined here