doctest: fix autouse fixtures possibly not getting picked up

bluetech · bluetech · commit 9cd14b4ffb1d · 2024-02-07T21:53:51.000+02:00
Fix #11929. Figured out what's going on. We have the following collection tree: ``` <Dir pyspacewar> <Dir src> <Package pyspacewar> <Package tests> <DoctestModule test_main.py> <DoctestItem pyspacewar.tests.test_main.doctest_main> ``` And the `test_main.py` contains an autouse fixture (`fake_game_ui`) that `doctest_main` needs in order to run properly. The fixture doesn't run! It doesn't run because nothing collects the fixtures from (calls `parsefactories()` on) the `test_main.py` `DoctestModule`. How come it only started happening with commit ab63ebb? Turns out it mostly only worked accidentally. Each `DoctestModule` is also collected as a normal `Module`, with the `Module` collected after the `DoctestModule`. For example, if we add a non-doctest test to `test_main.py`, the collection tree looks like this: ``` <Dir pyspacewar> <Dir src> <Package pyspacewar> <Package tests> <DoctestModule test_main.py> <DoctestItem pyspacewar.tests.test_main.doctest_main> <Module test_main.py> <Function test_it> ``` Now, `Module` *does* collect fixtures. When autouse fixtures are collected, they are added to the `_nodeid_autousenames` dict. Before ab63ebb, `DoctestItem` consults `_nodeid_autousenames` at *setup* time. At this point, the `Module` has collected and so it ended up picking the autouse fixture (this relies on another "accident", that the `DoctestModule` and `Module` have the same node ID). After ab63ebb, `DoctestItem` consults `_nodeid_autousenames` at *collection* time (= when it's created). At this point, the `Module` hasn't collected yet, so the autouse fixture is not picked out. The fix is simple -- have `DoctestModule.collect()` call `parsefactories`. From some testing I've done it shouldn't have negative consequences (I hope).
diff --git a/changelog/11929.bugfix.rst b/changelog/11929.bugfix.rst
@@ -0,0 +1 @@
+Fix a regression in pytest 8.0.0 whereby autouse fixtures defined in a module get ignored by the doctests in the module.
diff --git a/src/_pytest/doctest.py b/src/_pytest/doctest.py
@@ -567,6 +567,10 @@ def _from_module(self, module, object):
             else:
                 raise
 
+        # While doctests currently don't support fixtures directly, we still
+        # need to pick up autouse fixtures.
+        self.session._fixturemanager.parsefactories(self)
+
         # Uses internal doctest module parsing mechanism.
         finder = MockAwareDocTestFinder()
         optionflags = get_optionflags(self.config)
diff --git a/testing/test_doctest.py b/testing/test_doctest.py
@@ -1376,6 +1376,38 @@ def auto(request):
         str(result.stdout.no_fnmatch_line("*FAILURES*"))
         result.stdout.fnmatch_lines(["*=== 1 passed in *"])
 
+    @pytest.mark.parametrize("scope", [*SCOPES, "package"])
+    def test_auto_use_defined_in_same_module(
+        self, pytester: Pytester, scope: str
+    ) -> None:
+        """Autouse fixtures defined in the same module as the doctest get picked
+        up properly.
+
+        Regression test for #11929.
+        """
+        pytester.makepyfile(
+            f"""
+            import pytest
+
+            AUTO = "the fixture did not run"
+
+            @pytest.fixture(autouse=True, scope="{scope}")
+            def auto(request):
+                global AUTO
+                AUTO = "the fixture ran"
+
+            def my_doctest():
+                '''My doctest.
+
+                >>> my_doctest()
+                'the fixture ran'
+                '''
+                return AUTO
+            """
+        )
+        result = pytester.runpytest("--doctest-modules")
+        result.assert_outcomes(passed=1)
+
 
 class TestDoctestNamespaceFixture:
     SCOPES = ["module", "session", "class", "function"]

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1 @@`
	`1`	`+Fix a regression in pytest 8.0.0 whereby autouse fixtures defined in a module get ignored by the doctests in the module.`