fix target fixture registration post pytest 8.1

Author: dcendents

src/pytest_bdd/compat.py

@@ -24,13 +24,41 @@ def inject_fixture(request: FixtureRequest, arg: str, value: Any) -> None:
         :param arg: argument name
         :param value: argument value
         """
-
-        request._fixturemanager._register_fixture(
-            name=arg,
+        fd = FixtureDef(
+            config=request._fixturemanager.config,
+            baseid=request.node.nodeid,
+            argname=arg,
             func=lambda: value,
-            nodeid=request.node.nodeid,
+            scope="function",
+            params=None,
+            ids=None,
+            _ispytest=True,
         )
 
+        fd.cached_result = (value, 0, None)
+
+        old_fd = request._fixture_defs.get(arg)
+        add_fixturename = arg not in request.fixturenames
+
+        def fin() -> None:
+            request._fixturemanager._arg2fixturedefs[arg].remove(fd)
+
+            if old_fd is not None:
+                request._fixture_defs[arg] = old_fd
+
+            if add_fixturename:
+                request._pyfuncitem._fixtureinfo.names_closure.remove(arg)
+
+        request.addfinalizer(fin)
+
+        # inject fixture definition
+        request._fixturemanager._arg2fixturedefs.setdefault(arg, []).append(fd)
+
+        # inject fixture value in request cache
+        request._fixture_defs[arg] = fd
+        if add_fixturename:
+            request._pyfuncitem._fixtureinfo.names_closure.append(arg)
+
 else:
 
     def getfixturedefs(fixturemanager: FixtureManager, fixturename: str, node: Node) -> Sequence[FixtureDef] | None:

tests/steps/test_common.py

@@ -78,6 +78,48 @@ def _(bar, expected_value):
     assert bar == "test bar"
 
 
+def test_step_function_target_fixture_redefined(pytester):
+    pytester.makefile(
+        ".feature",
+        target_fixture=textwrap.dedent(
+            """\
+            Feature: Redefine a target fixture
+                Scenario: Redefine the target fixture after it has been injected once in the same scenario
+                    Given there is a foo with value "test foo"
+                    Then foo should be "test foo"
+                    Given there is a foo with value "test bar"
+                    Then foo should be "test bar"
+            """
+        ),
+    )
+    pytester.makepyfile(
+        textwrap.dedent(
+            """\
+        import pytest
+        from pytest_bdd import given, when, then, scenarios, parsers
+        from pytest_bdd.utils import dump_obj
+
+        scenarios("target_fixture.feature")
+
+        @given(parsers.parse('there is a foo with value "{value}"'), target_fixture="foo")
+        def _(value):
+            return value
+
+        @then(parsers.parse('foo should be "{expected_value}"'))
+        def _(foo, expected_value):
+            dump_obj(foo)
+            assert foo == expected_value
+        """
+        )
+    )
+    result = pytester.runpytest("-s")
+    result.assert_outcomes(passed=1)
+
+    [foo1, foo2] = collect_dumped_objects(result)
+    assert foo1 == "test foo"
+    assert foo2 == "test bar"
+
+
 def test_step_functions_same_parser(pytester):
     pytester.makefile(
         ".feature",