[AA-Turner]

The hashlib._HashObject stubs take ReadableBuffer in update() and the copy() method returns Self. Per the _typeshed module's README, the ReadableBuffer name can be used freely in stubs.

When running ty check in verbose mode, the following protocol member `copy` is incompatible error is currently reported, which is fixed by this change.

error[invalid-argument-type]: Argument to function `file_digest` is incorrect
  --> bug.py:10:42
   |
10 |     digest = hashlib.file_digest(source, xxhash.xxh128).hexdigest()
   |                                          ^^^^^^^^^^^^^ Expected `str | (() -> _HashObject)`, found `<class 'xxh3_128'>`
info: type `<class 'xxh3_128'>` is not assignable to any element of the union `str | (() -> _HashObject)`
info: ├── type `<class 'xxh3_128'>` has inferred callable type `(input: str | bytes | bytearray | memoryview[int] | array[int] = ..., seed: int = ...) -> xxh3_128`
info: │   └── incompatible return types: `xxh3_128` is not assignable to `_HashObject`
info: │       └── type `xxh3_128` is not assignable to protocol `_HashObject`
info: │           └── protocol member `copy` is incompatible
info: │               └── incompatible return types: `_Hasher` is not assignable to `xxh3_128`
info: └── ... omitted 1 union element without additional context
info: Function defined here
   --> stdlib/hashlib.pyi:161:9
    |
161 |     def file_digest(
    |         ^^^^^^^^^^^
162 |         fileobj: _BytesIOLike | _FileDigestFileObj, digest: str | Callable[[], _HashObject], /, *, _bufsize: int = 262144
    |                                                     --------------------------------------- Parameter declared here
info: rule `invalid-argument-type` is enabled by default

Found 1 diagnostic

[ifduyue]

Thank you！