fix: Add async context manager return types (#314)

* fix: Add async context manager return types

chore: Mock return_value should not populate oneof message fields

chore: Support snippet generation for services that only support REST transport

chore: Update gapic-generator-python to v1.11.0
PiperOrigin-RevId: 545430278

Source-Link: googleapis/googleapis@601b532

Source-Link: https://github.com/googleapis/googleapis-gen/commit/b3f18d0f6560a855022fd058865e7620479d7af9
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* 🦉 Updates from OwlBot post-processor

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google/cloud/video/transcoder_v1/services/transcoder_service/async_client.py

@@ -1077,7 +1077,7 @@ async def sample_delete_job_template():
             metadata=metadata,
         )
 
-    async def __aenter__(self):
+    async def __aenter__(self) -> "TranscoderServiceAsyncClient":
         return self
 
     async def __aexit__(self, exc_type, exc, tb):

samples/generated_samples/snippet_metadata_google.cloud.video.transcoder.v1.json

@@ -8,7 +8,7 @@
     ],
     "language": "PYTHON",
     "name": "google-cloud-video-transcoder",
-    "version": "1.9.0"
+    "version": "0.1.0"
   },
   "snippets": [
     {

tests/unit/gapic/transcoder_v1/test_transcoder_service.py

@@ -1411,9 +1411,11 @@ async def test_list_jobs_async_pages():
             RuntimeError,
         )
         pages = []
-        async for page_ in (
+        # Workaround issue in python 3.9 related to code coverage by adding `# pragma: no branch`
+        # See https://github.com/googleapis/gapic-generator-python/pull/1174#issuecomment-1025132372
+        async for page_ in (  # pragma: no branch
             await client.list_jobs(request={})
-        ).pages:  # pragma: no branch
+        ).pages:
             pages.append(page_)
         for page_, token in zip(pages, ["abc", "def", "ghi", ""]):
             assert page_.raw_page.next_page_token == token
@@ -2592,9 +2594,11 @@ async def test_list_job_templates_async_pages():
             RuntimeError,
         )
         pages = []
-        async for page_ in (
+        # Workaround issue in python 3.9 related to code coverage by adding `# pragma: no branch`
+        # See https://github.com/googleapis/gapic-generator-python/pull/1174#issuecomment-1025132372
+        async for page_ in (  # pragma: no branch
             await client.list_job_templates(request={})
-        ).pages:  # pragma: no branch
+        ).pages:
             pages.append(page_)
         for page_, token in zip(pages, ["abc", "def", "ghi", ""]):
             assert page_.raw_page.next_page_token == token