Short-circuit HTTP requests in tests (#12772)

tests/conftest.py

@@ -4,6 +4,7 @@ import gettext
 import os
 import sys
 from pathlib import Path
+from types import SimpleNamespace
 from typing import TYPE_CHECKING
 
 import docutils
@@ -60,3 +61,20 @@ def _cleanup_docutils() -> Iterator[None]:
     sys.path[:] = saved_path
 
     _clean_up_global_state()
+
+
+@pytest.fixture
+def _http_teapot(monkeypatch: pytest.MonkeyPatch) -> Iterator[None]:
+    """Short-circuit HTTP requests.
+
+    Windows takes too long to fail on connections, hence this fixture.
+    """
+    # https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/418
+    response = SimpleNamespace(status_code=418)
+
+    def _request(*args, **kwargs):
+        return response
+
+    with monkeypatch.context() as m:
+        m.setattr('sphinx.util.requests._Session.request', _request)
+        yield