Merge 95f53e32d7 into 2c5c97b6d1

src/_pytest/assertion/rewrite.py

@@ -17,6 +17,7 @@ from collections import defaultdict
 from pathlib import Path
 from pathlib import PurePath
 from typing import Callable
+from typing import DefaultDict
 from typing import Dict
 from typing import IO
 from typing import Iterable
@@ -668,9 +669,9 @@ class AssertionRewriter(ast.NodeVisitor):
         else:
             self.enable_assertion_pass_hook = False
         self.source = source
-        self.scope: tuple[ast.AST, ...] = ()
+        self.scope: Tuple[ast.AST, ...] = ()
-        self.variables_overwrite: defaultdict[
+        self.variables_overwrite: DefaultDict[
-            tuple[ast.AST, ...], Dict[str, str]
+            Tuple[ast.AST, ...], Dict[str, str]
         ] = defaultdict(dict)
 
     def run(self, mod: ast.Module) -> None:

src/_pytest/fixtures.py

@@ -314,33 +314,6 @@ class FuncFixtureInfo:
     # sequence is ordered from furthest to closes to the function.
     name2fixturedefs: Dict[str, Sequence["FixtureDef[Any]"]]
 
-    def prune_dependency_tree(self) -> None:
-        """Recompute names_closure from initialnames and name2fixturedefs.
-
-        Can only reduce names_closure, which means that the new closure will
-        always be a subset of the old one. The order is preserved.
-
-        This method is needed because direct parametrization may shadow some
-        of the fixtures that were included in the originally built dependency
-        tree. In this way the dependency tree can get pruned, and the closure
-        of argnames may get reduced.
-        """
-        closure: Set[str] = set()
-        working_set = set(self.initialnames)
-        while working_set:
-            argname = working_set.pop()
-            # Argname may be smth not included in the original names_closure,
-            # in which case we ignore it. This currently happens with pseudo
-            # FixtureDefs which wrap 'get_direct_param_fixture_func(request)'.
-            # So they introduce the new dependency 'request' which might have
-            # been missing in the original tree (closure).
-            if argname not in closure and argname in self.names_closure:
-                closure.add(argname)
-                if argname in self.name2fixturedefs:
-                    working_set.update(self.name2fixturedefs[argname][-1].argnames)
-
-        self.names_closure[:] = sorted(closure, key=self.names_closure.index)
-
 
 class FixtureRequest(abc.ABC):
     """The type of the ``request`` fixture.
@@ -961,7 +934,6 @@ def _eval_scope_callable(
     return result
 
 
-@final
 class FixtureDef(Generic[FixtureValue]):
     """A container for a fixture definition.
 
@@ -1104,6 +1076,26 @@ class FixtureDef(Generic[FixtureValue]):
         )
 
 
+class IdentityFixtureDef(FixtureDef[FixtureValue]):
+    def __init__(
+        self,
+        fixturemanager: "FixtureManager",
+        argname: str,
+        scope: Union[Scope, _ScopeName, Callable[[str, Config], _ScopeName], None],
+        *,
+        _ispytest: bool = False,
+    ):
+        super().__init__(
+            fixturemanager,
+            "",
+            argname,
+            lambda request: request.param,
+            scope,
+            None,
+            _ispytest=_ispytest,
+        )
+
+
 def resolve_fixture_function(
     fixturedef: FixtureDef[FixtureValue], request: FixtureRequest
 ) -> "_FixtureFunc[FixtureValue]":
@@ -1486,10 +1478,11 @@ class FixtureManager:
         initialnames = deduplicate_names(autousenames, usefixturesnames, argnames)
 
         direct_parametrize_args = _get_direct_parametrize_args(node)
-
+        arg2fixturedefs: Dict[str, Sequence[FixtureDef[Any]]] = {}
-        names_closure, arg2fixturedefs = self.getfixtureclosure(
+        names_closure = self.getfixtureclosure(
             parentnode=node,
             initialnames=initialnames,
+            arg2fixturedefs=arg2fixturedefs,
             ignore_args=direct_parametrize_args,
         )
 
@@ -1533,30 +1526,33 @@ class FixtureManager:
         self,
         parentnode: nodes.Node,
         initialnames: Tuple[str, ...],
+        arg2fixturedefs: Dict[str, Sequence[FixtureDef[Any]]],
         ignore_args: AbstractSet[str],
-    ) -> Tuple[List[str], Dict[str, Sequence[FixtureDef[Any]]]]:
+    ) -> List[str]:
         # Collect the closure of all fixtures, starting with the given
-        # fixturenames as the initial set.  As we have to visit all
+        # initialnames containing function arguments, `usefixture` markers
-        # factory definitions anyway, we also return an arg2fixturedefs
+        # and `autouse` fixtures as the initial set.  As we have to visit all
-        # mapping so that the caller can reuse it and does not have
+        # factory definitions anyway, we also populate arg2fixturedefs mapping
-        # to re-discover fixturedefs again for each fixturename
+        # for the args missing therein so that the caller can reuse it and does
+        # not have to re-discover fixturedefs again for each fixturename
         # (discovering matching fixtures for a given name/node is expensive).
 
         parentid = parentnode.nodeid
         fixturenames_closure = list(initialnames)
 
-        arg2fixturedefs: Dict[str, Sequence[FixtureDef[Any]]] = {}
         lastlen = -1
         while lastlen != len(fixturenames_closure):
             lastlen = len(fixturenames_closure)
             for argname in fixturenames_closure:
                 if argname in ignore_args:
                     continue
-                if argname in arg2fixturedefs:
+                if argname not in arg2fixturedefs:
-                    continue
                     fixturedefs = self.getfixturedefs(argname, parentid)
                     if fixturedefs:
                         arg2fixturedefs[argname] = fixturedefs
+                else:
+                    fixturedefs = arg2fixturedefs[argname]
+                if fixturedefs and not isinstance(fixturedefs[-1], IdentityFixtureDef):
                     for arg in fixturedefs[-1].argnames:
                         if arg not in fixturenames_closure:
                             fixturenames_closure.append(arg)
@@ -1570,7 +1566,7 @@ class FixtureManager:
                 return fixturedefs[-1]._scope
 
         fixturenames_closure.sort(key=sort_by_scope, reverse=True)
-        return fixturenames_closure, arg2fixturedefs
+        return fixturenames_closure
 
     def pytest_generate_tests(self, metafunc: "Metafunc") -> None:
         """Generate new tests based on parametrized fixtures used by the given metafunc"""

src/_pytest/python.py

@@ -59,10 +59,10 @@ from _pytest.config.argparsing import Parser
 from _pytest.deprecated import check_ispytest
 from _pytest.deprecated import INSTANCE_COLLECTOR
 from _pytest.deprecated import NOSE_SUPPORT_METHOD
-from _pytest.fixtures import FixtureDef
+from _pytest.fixtures import _get_direct_parametrize_args
-from _pytest.fixtures import FixtureRequest
 from _pytest.fixtures import FuncFixtureInfo
 from _pytest.fixtures import get_scope_node
+from _pytest.fixtures import IdentityFixtureDef
 from _pytest.main import Session
 from _pytest.mark import MARK_GEN
 from _pytest.mark import ParameterSet
@@ -488,8 +488,6 @@ class PyCollector(PyobjMixin, nodes.Collector, abc.ABC):
         )
         fixtureinfo = definition._fixtureinfo
 
-        # pytest_generate_tests impls call metafunc.parametrize() which fills
-        # metafunc._calls, the outcome of the hook.
         metafunc = Metafunc(
             definition=definition,
             fixtureinfo=fixtureinfo,
@@ -498,23 +496,32 @@ class PyCollector(PyobjMixin, nodes.Collector, abc.ABC):
             module=module,
             _ispytest=True,
         )
-        methods = []
+
+        def prune_dependency_tree_if_test_is_directly_parametrized(metafunc: Metafunc):
+            # Direct (those with `indirect=False`) parametrizations taking place in
+            # module/class-specific `pytest_generate_tests` hooks, a.k.a dynamic direct
+            # parametrizations using `metafunc.parametrize`, may have shadowed some
+            # fixtures, making some fixtures no longer reachable. Update the dependency
+            # tree to reflect what the item really needs.
+            # Note that direct parametrizations using `@pytest.mark.parametrize` have
+            # already been considered into making the closure using the `ignore_args`
+            # arg to `getfixtureclosure`.
+            if metafunc._has_direct_parametrization:
+                metafunc._update_dependency_tree()
+
+        methods = [prune_dependency_tree_if_test_is_directly_parametrized]
         if hasattr(module, "pytest_generate_tests"):
             methods.append(module.pytest_generate_tests)
         if cls is not None and hasattr(cls, "pytest_generate_tests"):
             methods.append(cls().pytest_generate_tests)
+
+        # pytest_generate_tests impls call metafunc.parametrize() which fills
+        # metafunc._calls, the outcome of the hook.
         self.ihook.pytest_generate_tests.call_extra(methods, dict(metafunc=metafunc))
 
         if not metafunc._calls:
             yield Function.from_parent(self, name=name, fixtureinfo=fixtureinfo)
         else:
-            # Direct parametrizations taking place in module/class-specific
-            # `metafunc.parametrize` calls may have shadowed some fixtures, so make sure
-            # we update what the function really needs a.k.a its fixture closure. Note that
-            # direct parametrizations using `@pytest.mark.parametrize` have already been considered
-            # into making the closure using `ignore_args` arg to `getfixtureclosure`.
-            fixtureinfo.prune_dependency_tree()
-
             for callspec in metafunc._calls:
                 subname = f"{name}[{callspec.id}]"
                 yield Function.from_parent(
@@ -1166,12 +1173,8 @@ class CallSpec2:
         return "-".join(self._idlist)
 
 
-def get_direct_param_fixture_func(request: FixtureRequest) -> Any:
-    return request.param
-
-
 # Used for storing pseudo fixturedefs for direct parametrization.
-name2pseudofixturedef_key = StashKey[Dict[str, FixtureDef[Any]]]()
+name2pseudofixturedef_key = StashKey[Dict[str, IdentityFixtureDef[Any]]]()
 
 
 @final
@@ -1218,6 +1221,9 @@ class Metafunc:
         # Result of parametrize().
         self._calls: List[CallSpec2] = []
 
+        # Whether it's ever been directly parametrized, i.e. with `indirect=False`.
+        self._has_direct_parametrization = False
+
     def parametrize(
         self,
         argnames: Union[str, Sequence[str]],
@@ -1358,7 +1364,7 @@ class Metafunc:
         if node is None:
             name2pseudofixturedef = None
         else:
-            default: Dict[str, FixtureDef[Any]] = {}
+            default: Dict[str, IdentityFixtureDef[Any]] = {}
             name2pseudofixturedef = node.stash.setdefault(
                 name2pseudofixturedef_key, default
             )
@@ -1366,18 +1372,14 @@ class Metafunc:
         for argname in argnames:
             if arg_directness[argname] == "indirect":
                 continue
+            self._has_direct_parametrization = True
             if name2pseudofixturedef is not None and argname in name2pseudofixturedef:
                 fixturedef = name2pseudofixturedef[argname]
             else:
-                fixturedef = FixtureDef(
+                fixturedef = IdentityFixtureDef(
-                    fixturemanager=self.definition.session._fixturemanager,
+                    self.definition.session._fixturemanager,
-                    baseid="",
+                    argname,
-                    argname=argname,
+                    scope_,
-                    func=get_direct_param_fixture_func,
-                    scope=scope_,
-                    params=None,
-                    unittest=False,
-                    ids=None,
                     _ispytest=True,
                 )
                 if name2pseudofixturedef is not None:
@@ -1543,6 +1545,18 @@ class Metafunc:
                         pytrace=False,
                     )
 
+    def _update_dependency_tree(self) -> None:
+        definition = self.definition
+        assert definition.parent is not None
+        fm = definition.parent.session._fixturemanager
+        fixture_closure = fm.getfixtureclosure(
+            parentnode=definition,
+            initialnames=definition._fixtureinfo.initialnames,
+            arg2fixturedefs=definition._fixtureinfo.name2fixturedefs,
+            ignore_args=_get_direct_parametrize_args(definition),
+        )
+        definition._fixtureinfo.names_closure[:] = fixture_closure
+
 
 def _find_parametrized_scope(
     argnames: Sequence[str],

testing/python/fixtures.py

@@ -4534,8 +4534,198 @@ def test_yield_fixture_with_no_value(pytester: Pytester) -> None:
     assert result.ret == ExitCode.TESTS_FAILED
 
 
+def test_fixture_info_after_dynamic_parametrize(pytester: Pytester) -> None:
+    """
+    Item dependency tree should get prunned before `FixtureManager::pytest_generate_tests`
+    hook implementation because it attempts to parametrize on the fixtures in the
+    fixture closure.
+    """
+    pytester.makeconftest(
+        """
+        import pytest
+
+        @pytest.fixture(scope='session', params=[0, 1])
+        def fixture1(request):
+            pass
+
+        @pytest.fixture(scope='session')
+        def fixture2(fixture1):
+            pass
+
+        @pytest.fixture(scope='session', params=[2, 3])
+        def fixture3(request, fixture2):
+            pass
+        """
+    )
+    pytester.makepyfile(
+        """
+        import pytest
+        def pytest_generate_tests(metafunc):
+            metafunc.parametrize("fixture2", [4, 5], scope='session')
+
+        @pytest.fixture(scope='session')
+        def fixture2(fixture3):
+            pass
+
+        def test(fixture2):
+            assert fixture2 in (4, 5)
+        """
+    )
+    res = pytester.runpytest()
+    res.assert_outcomes(passed=2)
+
+
+def test_reordering_after_dynamic_parametrize(pytester: Pytester):
+    """Make sure that prunning dependency tree takes place correctly, regarding from
+    reordering's viewpoint."""
+    pytester.makepyfile(
+        """
+        import pytest
+
+        def pytest_generate_tests(metafunc):
+            if metafunc.definition.name == "test_0":
+                metafunc.parametrize("fixture2", [0])
+
+        @pytest.fixture(scope='module', params=[0])
+        def fixture1():
+            pass
+
+        @pytest.fixture(scope='module')
+        def fixture2(fixture1):
+            pass
+
+        def test_0(fixture2):
+            pass
+
+        def test_1():
+            pass
+
+        def test_2(fixture1):
+            pass
+        """
+    )
+    result = pytester.runpytest("--collect-only")
+    result.stdout.fnmatch_lines(
+        [
+            "*test_0*",
+            "*test_1*",
+            "*test_2*",
+        ],
+        consecutive=True,
+    )
+
+
+def test_request_shouldnt_be_in_closure_after_pruning_dep_tree_when_its_not_in_initial_closure(
+    pytester: Pytester,
+):
+    """Make sure that fixture `request` doesn't show up in the closure after prunning dependency
+    tree when it has not been there beforehand.
+    """
+    pytester.makepyfile(
+        """
+        import pytest
+
+        def pytest_generate_tests(metafunc):
+            metafunc.parametrize("arg", [0])
+
+        @pytest.fixture()
+        def fixture():
+            pass
+
+        def test(fixture, arg):
+            pass
+        """
+    )
+    result = pytester.runpytest("--setup-show")
+    result.stdout.re_match_lines(
+        [
+            r".+test\[0\] \(fixtures used: arg, fixture\)\.",
+        ],
+    )
+
+
+def test_dont_recompute_dependency_tree_if_no_direct_dynamic_parametrize(
+    pytester: Pytester,
+):
+    """We should not update item's dependency tree when there's no direct dynamic
+    parametrization, i.e. `metafunc.parametrize(indirect=False)`s in module/class specific
+    `pytest_generate_tests` hooks, for the sake of efficiency.
+    """
+    pytester.makeconftest(
+        """
+        import pytest
+        from _pytest.config import hookimpl
+        from unittest.mock import Mock
+
+        original_method = None
+
+        @hookimpl(trylast=True)
+        def pytest_sessionstart(session):
+            global original_method
+            original_method = session._fixturemanager.getfixtureclosure
+            session._fixturemanager.getfixtureclosure = Mock(wraps=original_method)
+
+        @hookimpl(tryfirst=True)
+        def pytest_sessionfinish(session, exitstatus):
+            global original_method
+            session._fixturemanager.getfixtureclosure = original_method
+        """
+    )
+    pytester.makepyfile(
+        """
+        import pytest
+
+        def pytest_generate_tests(metafunc):
+            if metafunc.definition.name == "test_0":
+                metafunc.parametrize("fixture", [0])
+
+            if metafunc.definition.name == "test_4":
+                metafunc.parametrize("fixture", [0], indirect=True)
+
+
+        @pytest.fixture(scope='module')
+        def fixture():
+            pass
+
+        def test_0(fixture):
+            pass
+
+        def test_1():
+            pass
+
+        @pytest.mark.parametrize("fixture", [0])
+        def test_2(fixture):
+            pass
+
+        @pytest.mark.parametrize("fixture", [0], indirect=True)
+        def test_3(fixture):
+            pass
+
+        def test_4(fixture):
+            pass
+
+        @pytest.fixture
+        def fm(request):
+            yield request._fixturemanager
+
+        def test(fm):
+            calls = fm.getfixtureclosure.call_args_list
+            assert len(calls) == 7
+            assert calls[0].kwargs["parentnode"].nodeid.endswith("test_0")
+            assert calls[1].kwargs["parentnode"].nodeid.endswith("test_0")
+            assert calls[2].kwargs["parentnode"].nodeid.endswith("test_1")
+            assert calls[3].kwargs["parentnode"].nodeid.endswith("test_2")
+            assert calls[4].kwargs["parentnode"].nodeid.endswith("test_3")
+            assert calls[5].kwargs["parentnode"].nodeid.endswith("test_4")
+            assert calls[6].kwargs["parentnode"].nodeid.endswith("test")
+        """
+    )
+    reprec = pytester.runpytest()
+    reprec.assert_outcomes(passed=6)
+
+
 def test_deduplicate_names() -> None:
     items = deduplicate_names("abacd")
     assert items == ("a", "b", "c", "d")
-    items = deduplicate_names(items + ("g", "f", "g", "e", "b"))
+    items = deduplicate_names(items, ("g", "f", "g", "e", "b"))
     assert items == ("a", "b", "c", "d", "g", "f", "e")

testing/python/show_fixtures_per_test.py

@@ -1,3 +1,4 @@
+import pytest
 from _pytest.pytester import Pytester
 
 
@@ -252,3 +253,39 @@ def test_verbose_include_multiline_docstring(pytester: Pytester) -> None:
             "    Docstring content that extends into a third paragraph.",
         ]
     )
+
+
+@pytest.mark.xfail(
+    reason="python.py::show_fixtures_per_test uses arg2fixturedefs instead of fixtureclosure"
+)
+def test_should_not_show_fixtures_pruned_after_dynamic_parametrization(
+    pytester: Pytester,
+) -> None:
+    pytester.makepyfile(
+        """
+        import pytest
+
+        @pytest.fixture
+        def fixture1():
+            pass
+
+        @pytest.fixture
+        def fixture2(fixture1):
+            pass
+
+        @pytest.fixture
+        def fixture3(fixture2):
+            pass
+
+        def pytest_generate_tests(metafunc):
+            metafunc.parametrize("fixture3", [0])
+
+        def test(fixture3):
+            pass
+    """
+    )
+    result = pytester.runpytest("--fixtures-per-test")
+    result.stdout.re_match_lines(
+        [r"-+ fixtures used by test\[0\] -+", r"-+ \(.+\) -+", r"fixture3 -- .+"],
+        consecutive=True,
+    )