Fix flaky test isolation (#14691)

AUTHORS.rst

@@ -81,6 +81,7 @@ Contributors
 * Justus Magin -- napoleon improvements
 * Kazuya Take -- ``sphinx.testing.path`` bug fix
 * Kevin Dunn -- MathJax extension
+* Kilian Paul -- Docutils compatibility, intl tests, and viewcode fixes
 * KINEBUCHI Tomohiko -- typing Sphinx as well as docutils
 * Kurt McKee -- documentation updates
 * Lars Hupfeldt Nielsen - OpenSSL FIPS mode md5 bug fix

CHANGES.rst

@@ -19,6 +19,10 @@ Bugs fixed
 Testing
 -------
 
+* #14690: Fix test isolation issues caused by shared test directories and
+  inherited ``NO_COLOR`` and ``NO_COLOUR`` environment variables.
+  Patch by Kilian Paul
+
 Release 9.2.0 (released Oct 20, 2026)
 =====================================
 

tests/test_transforms/test_transforms_post_transforms.py

@@ -70,6 +70,7 @@ def test_missing_reference(app: SphinxTestApp) -> None:
 @pytest.mark.sphinx(
     'html',
     testroot='domain-py-python_use_unqualified_type_names',
+    srcdir='transforms-post_transforms-missing-reference-conditional',
     freshenv=True,
 )
 def test_missing_reference_conditional_pending_xref(app: SphinxTestApp) -> None:

tests/test_util/test_util_display.py

@@ -44,6 +44,8 @@ def test_status_iterator_length_0(app: SphinxTestApp) -> None:
 def test_status_iterator_verbosity_0(
     app: SphinxTestApp, monkeypatch: pytest.MonkeyPatch
 ) -> None:
+    monkeypatch.delenv('NO_COLOR', raising=False)
+    monkeypatch.delenv('NO_COLOUR', raising=False)
     monkeypatch.setenv('FORCE_COLOR', '1')
     logging.setup(app, app.status, app.warning)
 
@@ -64,6 +66,8 @@ def test_status_iterator_verbosity_0(
 def test_status_iterator_verbosity_1(
     app: SphinxTestApp, monkeypatch: pytest.MonkeyPatch
 ) -> None:
+    monkeypatch.delenv('NO_COLOR', raising=False)
+    monkeypatch.delenv('NO_COLOUR', raising=False)
     monkeypatch.setenv('FORCE_COLOR', '1')
     logging.setup(app, app.status, app.warning)