👌 Add warning log for config values that cannot be cached

tests/test_builders/test_build_warnings.py

@@ -70,3 +70,19 @@ def test_texinfo_warnings(app, warning):
     app.build(force_all=True)
     warnings_exp = TEXINFO_WARNINGS.format(root=re.escape(app.srcdir.as_posix()))
     _check_warnings(warnings_exp, warning.getvalue())
+
+
+def test_uncacheable_config_warning(make_app, tmp_path):
+    """Test than an unpickleable config value raises a warning."""
+    tmp_path.joinpath('conf.py').write_text("""
+my_config = lambda: None
+show_warning_types = True
+def setup(app):
+    app.add_config_value('my_config', None, 'env')
+    """, encoding='utf-8')
+    tmp_path.joinpath('index.rst').write_text('Test\n====\n', encoding='utf-8')
+    app = make_app(srcdir=tmp_path)
+    app.build()
+    assert strip_colors(app.warning.getvalue()).strip() == (
+        "WARNING: cannot cache unpickable configuration value: 'my_config' [config.cache]"
+    )

tests/test_config/test_config.py

@@ -22,7 +22,6 @@
 )
 from sphinx.deprecation import RemovedInSphinx90Warning
 from sphinx.errors import ConfigError, ExtensionError, VersionRequirementError
-from sphinx.util.console import strip_colors
 
 if TYPE_CHECKING:
     from collections.abc import Iterable
@@ -293,24 +292,6 @@ def check(
     assert counters[type(x['b'])] == 2
 
 
-def test_uncacheable_config_warning(make_app, tmp_path):
-    """Test than an unpickleable config value raises a warning."""
-    srcdir = tmp_path / 'srcdir123'
-    srcdir.mkdir()
-    srcdir.joinpath('conf.py').write_text("""
-my_config = lambda: None
-show_warning_types = True
-def setup(app):
-    app.add_config_value('my_config', None, 'env')
-    """, encoding='utf-8')
-    srcdir.joinpath('index.rst').write_text('Test\n====\n', encoding='utf-8')
-    app = make_app(srcdir=srcdir)
-    app.build()
-    assert strip_colors(app.warning.getvalue()).strip() == (
-        "WARNING: cannot cache unpickable configuration value: 'my_config' [config.cache]"
-    )
-
-
 def test_extension_values():
     config = Config()