Fix return type annotations for functions used with @contextmanager (#…

…8617)

Some of them are annotated with an `Iterator` return type. However...

It just occurred to me that `@contextmanager` cannot work with a
function that returns a plain iterator, since it relies on the generator
class's `throw` method. `contextmanager` is defined in typeshed as
accepting an iterator-returning function, but that appears to be a bug:
<python/typeshed#2772>.

Change all such annotations to a `Generator` type instead.

Some annotations are also broken in other ways; fix them too.

cvat-sdk/cvat_sdk/core/client.py

@@ -10,7 +10,7 @@
 from contextlib import contextmanager, suppress
 from pathlib import Path
 from time import sleep
-from typing import Any, Dict, Iterator, Optional, Sequence, Tuple, TypeVar
+from typing import Any, Dict, Generator, Optional, Sequence, Tuple, TypeVar
 
 import attrs
 import packaging.specifiers as specifiers
@@ -121,7 +121,7 @@ def organization_slug(self, org_slug: Optional[str]):
             self.api_client.default_headers[self._ORG_SLUG_HEADER] = org_slug
 
     @contextmanager
-    def organization_context(self, slug: str) -> Iterator[None]:
+    def organization_context(self, slug: str) -> Generator[None, None, None]:
         prev_slug = self.organization_slug
         self.organization_slug = slug
         try:

cvat-sdk/cvat_sdk/core/progress.py

@@ -6,7 +6,7 @@
 from __future__ import annotations
 
 import contextlib
-from typing import ContextManager, Iterable, Optional, TypeVar
+from typing import Generator, Iterable, Optional, TypeVar
 
 T = TypeVar("T")
 
@@ -26,7 +26,7 @@ class ProgressReporter:
     """
 
     @contextlib.contextmanager
-    def task(self, **kwargs) -> ContextManager[None]:
+    def task(self, **kwargs) -> Generator[None, None, None]:
         """
         Returns a context manager that represents a long-running task
         for which progress can be reported.

cvat-sdk/cvat_sdk/core/utils.py

@@ -13,7 +13,7 @@
     BinaryIO,
     ContextManager,
     Dict,
-    Iterator,
+    Generator,
     Literal,
     Sequence,
     TextIO,
@@ -43,7 +43,7 @@ def atomic_writer(
 @contextlib.contextmanager
 def atomic_writer(
     path: Union[os.PathLike, str], mode: Literal["w", "wb"], encoding: str = "UTF-8"
-) -> Iterator[IO]:
+) -> Generator[IO, None, None]:
     """
     Returns a context manager that, when entered, returns a handle to a temporary
     file opened with the specified `mode` and `encoding`. If the context manager

cvat/apps/engine/media_extractors.py

@@ -539,7 +539,9 @@ def extract(self):
 
 class _AvVideoReading:
     @contextmanager
-    def read_av_container(self, source: Union[str, io.BytesIO]) -> av.container.InputContainer:
+    def read_av_container(
+        self, source: Union[str, io.BytesIO]
+    ) -> Generator[av.container.InputContainer, None, None]:
         if isinstance(source, io.BytesIO):
             source.seek(0) # required for re-reading
 

tests/python/cli/util.py

@@ -9,7 +9,7 @@
 import threading
 import unittest
 from pathlib import Path
-from typing import Any, Dict, Iterator, List, Union
+from typing import Any, Dict, Generator, List, Union
 
 import requests
 
@@ -39,7 +39,7 @@ def generate_images(dst_dir: Path, count: int) -> List[Path]:
 
 
 @contextlib.contextmanager
-def https_reverse_proxy() -> Iterator[str]:
+def https_reverse_proxy() -> Generator[str, None, None]:
     ssl_context = ssl.SSLContext(ssl.PROTOCOL_TLS_SERVER)
     ssl_context.minimum_version = ssl.TLSVersion.TLSv1_2
     cert_dir = Path(__file__).parent