Add consider_namespace_packages ini option

Fix #11475

src/_pytest/config/__init__.py

@@ -547,6 +547,8 @@ class PytestPluginManager(PluginManager):
         confcutdir: Optional[Path],
         invocation_dir: Path,
         importmode: Union[ImportMode, str],
+        *,
+        consider_namespace_packages: bool,
     ) -> None:
         """Load initial conftest files given a preparsed "namespace".
 
@@ -572,10 +574,20 @@ class PytestPluginManager(PluginManager):
             # Ensure we do not break if what appears to be an anchor
             # is in fact a very long option (#10169, #11394).
             if safe_exists(anchor):
-                self._try_load_conftest(anchor, importmode, rootpath)
+                self._try_load_conftest(
+                    anchor,
+                    importmode,
+                    rootpath,
+                    consider_namespace_packages=consider_namespace_packages,
+                )
                 foundanchor = True
         if not foundanchor:
-            self._try_load_conftest(invocation_dir, importmode, rootpath)
+            self._try_load_conftest(
+                invocation_dir,
+                importmode,
+                rootpath,
+                consider_namespace_packages=consider_namespace_packages,
+            )
 
     def _is_in_confcutdir(self, path: Path) -> bool:
         """Whether to consider the given path to load conftests from."""
@@ -593,17 +605,37 @@ class PytestPluginManager(PluginManager):
         return path not in self._confcutdir.parents
 
     def _try_load_conftest(
-        self, anchor: Path, importmode: Union[str, ImportMode], rootpath: Path
+        self,
+        anchor: Path,
+        importmode: Union[str, ImportMode],
+        rootpath: Path,
+        *,
+        consider_namespace_packages: bool,
     ) -> None:
-        self._loadconftestmodules(anchor, importmode, rootpath)
+        self._loadconftestmodules(
+            anchor,
+            importmode,
+            rootpath,
+            consider_namespace_packages=consider_namespace_packages,
+        )
         # let's also consider test* subdirs
         if anchor.is_dir():
             for x in anchor.glob("test*"):
                 if x.is_dir():
-                    self._loadconftestmodules(x, importmode, rootpath)
+                    self._loadconftestmodules(
+                        x,
+                        importmode,
+                        rootpath,
+                        consider_namespace_packages=consider_namespace_packages,
+                    )
 
     def _loadconftestmodules(
-        self, path: Path, importmode: Union[str, ImportMode], rootpath: Path
+        self,
+        path: Path,
+        importmode: Union[str, ImportMode],
+        rootpath: Path,
+        *,
+        consider_namespace_packages: bool,
     ) -> None:
         if self._noconftest:
             return
@@ -620,7 +652,12 @@ class PytestPluginManager(PluginManager):
             if self._is_in_confcutdir(parent):
                 conftestpath = parent / "conftest.py"
                 if conftestpath.is_file():
-                    mod = self._importconftest(conftestpath, importmode, rootpath)
+                    mod = self._importconftest(
+                        conftestpath,
+                        importmode,
+                        rootpath,
+                        consider_namespace_packages=consider_namespace_packages,
+                    )
                     clist.append(mod)
         self._dirpath2confmods[directory] = clist
 
@@ -642,7 +679,12 @@ class PytestPluginManager(PluginManager):
         raise KeyError(name)
 
     def _importconftest(
-        self, conftestpath: Path, importmode: Union[str, ImportMode], rootpath: Path
+        self,
+        conftestpath: Path,
+        importmode: Union[str, ImportMode],
+        rootpath: Path,
+        *,
+        consider_namespace_packages: bool,
     ) -> types.ModuleType:
         conftestpath_plugin_name = str(conftestpath)
         existing = self.get_plugin(conftestpath_plugin_name)
@@ -661,7 +703,12 @@ class PytestPluginManager(PluginManager):
                 pass
 
         try:
-            mod = import_path(conftestpath, mode=importmode, root=rootpath)
+            mod = import_path(
+                conftestpath,
+                mode=importmode,
+                root=rootpath,
+                consider_namespace_packages=consider_namespace_packages,
+            )
         except Exception as e:
             assert e.__traceback__ is not None
             raise ConftestImportFailure(conftestpath, cause=e) from e
@@ -1177,6 +1224,9 @@ class Config:
             confcutdir=early_config.known_args_namespace.confcutdir,
             invocation_dir=early_config.invocation_params.dir,
             importmode=early_config.known_args_namespace.importmode,
+            consider_namespace_packages=early_config.getini(
+                "consider_namespace_packages"
+            ),
         )
 
     def _initini(self, args: Sequence[str]) -> None:

src/_pytest/main.py

@@ -222,6 +222,12 @@ def pytest_addoption(parser: Parser) -> None:
         help="Prepend/append to sys.path when importing test modules and conftest "
         "files. Default: prepend.",
     )
+    parser.addini(
+        "consider_namespace_packages",
+        type="bool",
+        default=False,
+        help="Consider namespace packages when resolving module names during import",
+    )
 
     group = parser.getgroup("debugconfig", "test session debugging and configuration")
     group.addoption(

src/_pytest/pathlib.py

@@ -488,6 +488,7 @@ def import_path(
     *,
     mode: Union[str, ImportMode] = ImportMode.prepend,
     root: Path,
+    consider_namespace_packages: bool,
 ) -> ModuleType:
     """
     Import and return a module from the given path, which can be a file (a module) or
@@ -515,6 +516,9 @@ def import_path(
         a unique name for the module being imported so it can safely be stored
         into ``sys.modules``.
 
+    :param consider_namespace_packages:
+        If True, consider namespace packages when resolving module names.
+
     :raises ImportPathMismatchError:
         If after importing the given `path` and the module `__file__`
         are different. Only raised in `prepend` and `append` modes.
@@ -530,7 +534,7 @@ def import_path(
         # without touching sys.path.
         try:
             pkg_root, module_name = resolve_pkg_root_and_module_name(
-                path, consider_ns_packages=True
+                path, consider_namespace_packages=consider_namespace_packages
             )
         except CouldNotResolvePathError:
             pass
@@ -556,7 +560,7 @@ def import_path(
 
     try:
         pkg_root, module_name = resolve_pkg_root_and_module_name(
-            path, consider_ns_packages=True
+            path, consider_namespace_packages=consider_namespace_packages
         )
     except CouldNotResolvePathError:
         pkg_root, module_name = path.parent, path.stem
@@ -674,7 +678,7 @@ def module_name_from_path(path: Path, root: Path) -> str:
     # Module names cannot contain ".", normalize them to "_". This prevents
     # a directory having a "." in the name (".env.310" for example) causing extra intermediate modules.
     # Also, important to replace "." at the start of paths, as those are considered relative imports.
-    path_parts = [x.replace(".", "_") for x in path_parts]
+    path_parts = tuple(x.replace(".", "_") for x in path_parts)
 
     return ".".join(path_parts)
 
@@ -738,7 +742,7 @@ def resolve_package_path(path: Path) -> Optional[Path]:
 
 
 def resolve_pkg_root_and_module_name(
-    path: Path, *, consider_ns_packages: bool = False
+    path: Path, *, consider_namespace_packages: bool = False
 ) -> Tuple[Path, str]:
     """
     Return the path to the directory of the root package that contains the
@@ -753,7 +757,7 @@ def resolve_pkg_root_and_module_name(
 
     Passing the full path to `models.py` will yield Path("src") and "app.core.models".
 
-    If consider_ns_packages is True, then we additionally check upwards in the hierarchy
+    If consider_namespace_packages is True, then we additionally check upwards in the hierarchy
     until we find a directory that is reachable from sys.path, which marks it as a namespace package:
 
     https://packaging.python.org/en/latest/guides/packaging-namespace-packages
@@ -764,7 +768,7 @@ def resolve_pkg_root_and_module_name(
     if pkg_path is not None:
         pkg_root = pkg_path.parent
         # https://packaging.python.org/en/latest/guides/packaging-namespace-packages/
-        if consider_ns_packages:
+        if consider_namespace_packages:
             # Go upwards in the hierarchy, if we find a parent path included
             # in sys.path, it means the package found by resolve_package_path()
             # actually belongs to a namespace package.

src/_pytest/python.py

@@ -516,7 +516,12 @@ def importtestmodule(
     # We assume we are only called once per module.
     importmode = config.getoption("--import-mode")
     try:
-        mod = import_path(path, mode=importmode, root=config.rootpath)
+        mod = import_path(
+            path,
+            mode=importmode,
+            root=config.rootpath,
+            consider_namespace_packages=config.getini("consider_namespace_packages"),
+        )
     except SyntaxError as e:
         raise nodes.Collector.CollectError(
             ExceptionInfo.from_current().getrepr(style="short")

src/_pytest/runner.py

@@ -380,6 +380,9 @@ def pytest_make_collect_report(collector: Collector) -> CollectReport:
                 collector.path,
                 collector.config.getoption("importmode"),
                 rootpath=collector.config.rootpath,
+                consider_namespace_packages=collector.config.getini(
+                    "consider_namespace_packages"
+                ),
             )
 
         return list(collector.collect())

testing/code/test_excinfo.py

@@ -180,7 +180,7 @@ class TestTraceback_f_g_h:
     def test_traceback_cut_excludepath(self, pytester: Pytester) -> None:
         p = pytester.makepyfile("def f(): raise ValueError")
         with pytest.raises(ValueError) as excinfo:
-            import_path(p, root=pytester.path).f()  # type: ignore[attr-defined]
+            import_path(p, root=pytester.path, consider_namespace_packages=False).f()  # type: ignore[attr-defined]
         basedir = Path(pytest.__file__).parent
         newtraceback = excinfo.traceback.cut(excludepath=basedir)
         for x in newtraceback:
@@ -543,7 +543,9 @@ class TestFormattedExcinfo:
             tmp_path.joinpath("__init__.py").touch()
             modpath.write_text(source, encoding="utf-8")
             importlib.invalidate_caches()
-            return import_path(modpath, root=tmp_path)
+            return import_path(
+                modpath, root=tmp_path, consider_namespace_packages=False
+            )
 
         return importasmod
 

testing/code/test_source.py

@@ -296,7 +296,7 @@ def test_source_of_class_at_eof_without_newline(_sys_snapshot, tmp_path: Path) -
     )
     path = tmp_path.joinpath("a.py")
     path.write_text(str(source), encoding="utf-8")
-    mod: Any = import_path(path, root=tmp_path)
+    mod: Any = import_path(path, root=tmp_path, consider_namespace_packages=False)
     s2 = Source(mod.A)
     assert str(source).strip() == str(s2).strip()
 

testing/test_conftest.py

@@ -38,6 +38,7 @@ def conftest_setinitial(
         confcutdir=confcutdir,
         invocation_dir=Path.cwd(),
         importmode="prepend",
+        consider_namespace_packages=False,
     )
 
 
@@ -64,7 +65,9 @@ class TestConftestValueAccessGlobal:
     def test_basic_init(self, basedir: Path) -> None:
         conftest = PytestPluginManager()
         p = basedir / "adir"
-        conftest._loadconftestmodules(p, importmode="prepend", rootpath=basedir)
+        conftest._loadconftestmodules(
+            p, importmode="prepend", rootpath=basedir, consider_namespace_packages=False
+        )
         assert conftest._rget_with_confmod("a", p)[1] == 1
 
     def test_immediate_initialiation_and_incremental_are_the_same(
@@ -72,15 +75,26 @@ class TestConftestValueAccessGlobal:
     ) -> None:
         conftest = PytestPluginManager()
         assert not len(conftest._dirpath2confmods)
-        conftest._loadconftestmodules(basedir, importmode="prepend", rootpath=basedir)
+        conftest._loadconftestmodules(
+            basedir,
+            importmode="prepend",
+            rootpath=basedir,
+            consider_namespace_packages=False,
+        )
         snap1 = len(conftest._dirpath2confmods)
         assert snap1 == 1
         conftest._loadconftestmodules(
-            basedir / "adir", importmode="prepend", rootpath=basedir
+            basedir / "adir",
+            importmode="prepend",
+            rootpath=basedir,
+            consider_namespace_packages=False,
         )
         assert len(conftest._dirpath2confmods) == snap1 + 1
         conftest._loadconftestmodules(
-            basedir / "b", importmode="prepend", rootpath=basedir
+            basedir / "b",
+            importmode="prepend",
+            rootpath=basedir,
+            consider_namespace_packages=False,
         )
         assert len(conftest._dirpath2confmods) == snap1 + 2
 
@@ -92,10 +106,18 @@ class TestConftestValueAccessGlobal:
     def test_value_access_by_path(self, basedir: Path) -> None:
         conftest = ConftestWithSetinitial(basedir)
         adir = basedir / "adir"
-        conftest._loadconftestmodules(adir, importmode="prepend", rootpath=basedir)
+        conftest._loadconftestmodules(
+            adir,
+            importmode="prepend",
+            rootpath=basedir,
+            consider_namespace_packages=False,
+        )
         assert conftest._rget_with_confmod("a", adir)[1] == 1
         conftest._loadconftestmodules(
-            adir / "b", importmode="prepend", rootpath=basedir
+            adir / "b",
+            importmode="prepend",
+            rootpath=basedir,
+            consider_namespace_packages=False,
         )
         assert conftest._rget_with_confmod("a", adir / "b")[1] == 1.5
 
@@ -152,7 +174,12 @@ def test_conftest_global_import(pytester: Pytester) -> None:
         import pytest
         from _pytest.config import PytestPluginManager
         conf = PytestPluginManager()
-        mod = conf._importconftest(Path("conftest.py"), importmode="prepend", rootpath=Path.cwd())
+        mod = conf._importconftest(
+            Path("conftest.py"),
+            importmode="prepend",
+            rootpath=Path.cwd(),
+            consider_namespace_packages=False,
+        )
         assert mod.x == 3
         import conftest
         assert conftest is mod, (conftest, mod)
@@ -160,7 +187,12 @@ def test_conftest_global_import(pytester: Pytester) -> None:
         sub.mkdir()
         subconf = sub / "conftest.py"
         subconf.write_text("y=4", encoding="utf-8")
-        mod2 = conf._importconftest(subconf, importmode="prepend", rootpath=Path.cwd())
+        mod2 = conf._importconftest(
+            subconf,
+            importmode="prepend",
+            rootpath=Path.cwd(),
+            consider_namespace_packages=False,
+        )
         assert mod != mod2
         assert mod2.y == 4
         import conftest
@@ -176,17 +208,30 @@ def test_conftestcutdir(pytester: Pytester) -> None:
     p = pytester.mkdir("x")
     conftest = PytestPluginManager()
     conftest_setinitial(conftest, [pytester.path], confcutdir=p)
-    conftest._loadconftestmodules(p, importmode="prepend", rootpath=pytester.path)
+    conftest._loadconftestmodules(
+        p,
+        importmode="prepend",
+        rootpath=pytester.path,
+        consider_namespace_packages=False,
+    )
     values = conftest._getconftestmodules(p)
     assert len(values) == 0
     conftest._loadconftestmodules(
-        conf.parent, importmode="prepend", rootpath=pytester.path
+        conf.parent,
+        importmode="prepend",
+        rootpath=pytester.path,
+        consider_namespace_packages=False,
     )
     values = conftest._getconftestmodules(conf.parent)
     assert len(values) == 0
     assert not conftest.has_plugin(str(conf))
     # but we can still import a conftest directly
-    conftest._importconftest(conf, importmode="prepend", rootpath=pytester.path)
+    conftest._importconftest(
+        conf,
+        importmode="prepend",
+        rootpath=pytester.path,
+        consider_namespace_packages=False,
+    )
     values = conftest._getconftestmodules(conf.parent)
     assert values[0].__file__ is not None
     assert values[0].__file__.startswith(str(conf))
@@ -405,13 +450,18 @@ def test_conftest_import_order(pytester: Pytester, monkeypatch: MonkeyPatch) ->
     ct2 = sub / "conftest.py"
     ct2.write_text("", encoding="utf-8")
 
-    def impct(p, importmode, root):
+    def impct(p, importmode, root, consider_namespace_packages):
         return p
 
     conftest = PytestPluginManager()
     conftest._confcutdir = pytester.path
     monkeypatch.setattr(conftest, "_importconftest", impct)
-    conftest._loadconftestmodules(sub, importmode="prepend", rootpath=pytester.path)
+    conftest._loadconftestmodules(
+        sub,
+        importmode="prepend",
+        rootpath=pytester.path,
+        consider_namespace_packages=False,
+    )
     mods = cast(List[Path], conftest._getconftestmodules(sub))
     expected = [ct1, ct2]
     assert mods == expected

testing/test_pathlib.py

@@ -171,13 +171,17 @@ class TestImportPath:
         )
 
     def test_smoke_test(self, path1: Path) -> None:
-        obj = import_path(path1 / "execfile.py", root=path1)
+        obj = import_path(
+            path1 / "execfile.py", root=path1, consider_namespace_packages=False
+        )
         assert obj.x == 42  # type: ignore[attr-defined]
         assert obj.__name__ == "execfile"
 
     def test_import_path_missing_file(self, path1: Path) -> None:
         with pytest.raises(ImportPathMismatchError):
-            import_path(path1 / "sampledir", root=path1)
+            import_path(
+                path1 / "sampledir", root=path1, consider_namespace_packages=False
+            )
 
     def test_renamed_dir_creates_mismatch(
         self, tmp_path: Path, monkeypatch: MonkeyPatch
@@ -185,25 +189,37 @@ class TestImportPath:
         tmp_path.joinpath("a").mkdir()
         p = tmp_path.joinpath("a", "test_x123.py")
         p.touch()
-        import_path(p, root=tmp_path)
+        import_path(p, root=tmp_path, consider_namespace_packages=False)
         tmp_path.joinpath("a").rename(tmp_path.joinpath("b"))
         with pytest.raises(ImportPathMismatchError):
-            import_path(tmp_path.joinpath("b", "test_x123.py"), root=tmp_path)
+            import_path(
+                tmp_path.joinpath("b", "test_x123.py"),
+                root=tmp_path,
+                consider_namespace_packages=False,
+            )
 
         # Errors can be ignored.
         monkeypatch.setenv("PY_IGNORE_IMPORTMISMATCH", "1")
-        import_path(tmp_path.joinpath("b", "test_x123.py"), root=tmp_path)
+        import_path(
+            tmp_path.joinpath("b", "test_x123.py"),
+            root=tmp_path,
+            consider_namespace_packages=False,
+        )
 
         # PY_IGNORE_IMPORTMISMATCH=0 does not ignore error.
         monkeypatch.setenv("PY_IGNORE_IMPORTMISMATCH", "0")
         with pytest.raises(ImportPathMismatchError):
-            import_path(tmp_path.joinpath("b", "test_x123.py"), root=tmp_path)
+            import_path(
+                tmp_path.joinpath("b", "test_x123.py"),
+                root=tmp_path,
+                consider_namespace_packages=False,
+            )
 
     def test_messy_name(self, tmp_path: Path) -> None:
         # https://bitbucket.org/hpk42/py-trunk/issue/129
         path = tmp_path / "foo__init__.py"
         path.touch()
-        module = import_path(path, root=tmp_path)
+        module = import_path(path, root=tmp_path, consider_namespace_packages=False)
         assert module.__name__ == "foo__init__"
 
     def test_dir(self, tmp_path: Path) -> None:
@@ -211,31 +227,39 @@ class TestImportPath:
         p.mkdir()
         p_init = p / "__init__.py"
         p_init.touch()
-        m = import_path(p, root=tmp_path)
+        m = import_path(p, root=tmp_path, consider_namespace_packages=False)
         assert m.__name__ == "hello_123"
-        m = import_path(p_init, root=tmp_path)
+        m = import_path(p_init, root=tmp_path, consider_namespace_packages=False)
         assert m.__name__ == "hello_123"
 
     def test_a(self, path1: Path) -> None:
         otherdir = path1 / "otherdir"
-        mod = import_path(otherdir / "a.py", root=path1)
+        mod = import_path(
+            otherdir / "a.py", root=path1, consider_namespace_packages=False
+        )
         assert mod.result == "got it"  # type: ignore[attr-defined]
         assert mod.__name__ == "otherdir.a"
 
     def test_b(self, path1: Path) -> None:
         otherdir = path1 / "otherdir"
-        mod = import_path(otherdir / "b.py", root=path1)
+        mod = import_path(
+            otherdir / "b.py", root=path1, consider_namespace_packages=False
+        )
         assert mod.stuff == "got it"  # type: ignore[attr-defined]
         assert mod.__name__ == "otherdir.b"
 
     def test_c(self, path1: Path) -> None:
         otherdir = path1 / "otherdir"
-        mod = import_path(otherdir / "c.py", root=path1)
+        mod = import_path(
+            otherdir / "c.py", root=path1, consider_namespace_packages=False
+        )
         assert mod.value == "got it"  # type: ignore[attr-defined]
 
     def test_d(self, path1: Path) -> None:
         otherdir = path1 / "otherdir"
-        mod = import_path(otherdir / "d.py", root=path1)
+        mod = import_path(
+            otherdir / "d.py", root=path1, consider_namespace_packages=False
+        )
         assert mod.value2 == "got it"  # type: ignore[attr-defined]
 
     def test_import_after(self, tmp_path: Path) -> None:
@@ -243,7 +267,7 @@ class TestImportPath:
         tmp_path.joinpath("xxxpackage", "__init__.py").touch()
         mod1path = tmp_path.joinpath("xxxpackage", "module1.py")
         mod1path.touch()
-        mod1 = import_path(mod1path, root=tmp_path)
+        mod1 = import_path(mod1path, root=tmp_path, consider_namespace_packages=False)
         assert mod1.__name__ == "xxxpackage.module1"
         from xxxpackage import module1
 
@@ -262,7 +286,9 @@ class TestImportPath:
                 pseudopath.touch()
                 mod.__file__ = str(pseudopath)
                 mp.setitem(sys.modules, name, mod)
-                newmod = import_path(p, root=tmp_path)
+                newmod = import_path(
+                    p, root=tmp_path, consider_namespace_packages=False
+                )
                 assert mod == newmod
         mod = ModuleType(name)
         pseudopath = tmp_path.joinpath(name + "123.py")
@@ -270,7 +296,7 @@ class TestImportPath:
         mod.__file__ = str(pseudopath)
         monkeypatch.setitem(sys.modules, name, mod)
         with pytest.raises(ImportPathMismatchError) as excinfo:
-            import_path(p, root=tmp_path)
+            import_path(p, root=tmp_path, consider_namespace_packages=False)
         modname, modfile, orig = excinfo.value.args
         assert modname == name
         assert modfile == str(pseudopath)
@@ -283,13 +309,19 @@ class TestImportPath:
         file1 = root1 / "x123.py"
         file1.touch()
         assert str(root1) not in sys.path
-        import_path(file1, mode="append", root=tmp_path)
+        import_path(
+            file1, mode="append", root=tmp_path, consider_namespace_packages=False
+        )
         assert str(root1) == sys.path[-1]
         assert str(root1) not in sys.path[:-1]
 
     def test_invalid_path(self, tmp_path: Path) -> None:
         with pytest.raises(ImportError):
-            import_path(tmp_path / "invalid.py", root=tmp_path)
+            import_path(
+                tmp_path / "invalid.py",
+                root=tmp_path,
+                consider_namespace_packages=False,
+            )
 
     @pytest.fixture
     def simple_module(
@@ -307,7 +339,12 @@ class TestImportPath:
         self, simple_module: Path, tmp_path: Path, request: pytest.FixtureRequest
     ) -> None:
         """`importlib` mode does not change sys.path."""
-        module = import_path(simple_module, mode="importlib", root=tmp_path)
+        module = import_path(
+            simple_module,
+            mode="importlib",
+            root=tmp_path,
+            consider_namespace_packages=False,
+        )
         assert module.foo(2) == 42  # type: ignore[attr-defined]
         assert str(simple_module.parent) not in sys.path
         assert module.__name__ in sys.modules
@@ -319,8 +356,18 @@ class TestImportPath:
         self, simple_module: Path, tmp_path: Path
     ) -> None:
         """`importlib` mode called remembers previous module (#10341, #10811)."""
-        module1 = import_path(simple_module, mode="importlib", root=tmp_path)
+        module1 = import_path(
-        module2 = import_path(simple_module, mode="importlib", root=tmp_path)
+            simple_module,
+            mode="importlib",
+            root=tmp_path,
+            consider_namespace_packages=False,
+        )
+        module2 = import_path(
+            simple_module,
+            mode="importlib",
+            root=tmp_path,
+            consider_namespace_packages=False,
+        )
         assert module1 is module2
 
     def test_no_meta_path_found(
@@ -328,7 +375,12 @@ class TestImportPath:
     ) -> None:
         """Even without any meta_path should still import module."""
         monkeypatch.setattr(sys, "meta_path", [])
-        module = import_path(simple_module, mode="importlib", root=tmp_path)
+        module = import_path(
+            simple_module,
+            mode="importlib",
+            root=tmp_path,
+            consider_namespace_packages=False,
+        )
         assert module.foo(2) == 42  # type: ignore[attr-defined]
 
         # mode='importlib' fails if no spec is found to load the module
@@ -341,7 +393,12 @@ class TestImportPath:
             importlib.util, "spec_from_file_location", lambda *args: None
         )
         with pytest.raises(ImportError):
-            import_path(simple_module, mode="importlib", root=tmp_path)
+            import_path(
+                simple_module,
+                mode="importlib",
+                root=tmp_path,
+                consider_namespace_packages=False,
+            )
 
 
 def test_resolve_package_path(tmp_path: Path) -> None:
@@ -477,7 +534,9 @@ def test_samefile_false_negatives(tmp_path: Path, monkeypatch: MonkeyPatch) -> N
         # the paths too. Using a context to narrow the patch as much as possible given
         # this is an important system function.
         mp.setattr(os.path, "samefile", lambda x, y: False)
-        module = import_path(module_path, root=tmp_path)
+        module = import_path(
+            module_path, root=tmp_path, consider_namespace_packages=False
+        )
     assert getattr(module, "foo")() == 42
 
 
@@ -499,7 +558,9 @@ class TestImportLibMode:
             encoding="utf-8",
         )
 
-        module = import_path(fn, mode="importlib", root=tmp_path)
+        module = import_path(
+            fn, mode="importlib", root=tmp_path, consider_namespace_packages=False
+        )
         Data: Any = getattr(module, "Data")
         data = Data(value="foo")
         assert data.value == "foo"
@@ -525,7 +586,9 @@ class TestImportLibMode:
             encoding="utf-8",
         )
 
-        module = import_path(fn, mode="importlib", root=tmp_path)
+        module = import_path(
+            fn, mode="importlib", root=tmp_path, consider_namespace_packages=False
+        )
         round_trip = getattr(module, "round_trip")
         action = round_trip()
         assert action() == 42
@@ -575,10 +638,14 @@ class TestImportLibMode:
             s = pickle.dumps(obj)
             return pickle.loads(s)
 
-        module = import_path(fn1, mode="importlib", root=tmp_path)
+        module = import_path(
+            fn1, mode="importlib", root=tmp_path, consider_namespace_packages=False
+        )
         Data1 = getattr(module, "Data")
 
-        module = import_path(fn2, mode="importlib", root=tmp_path)
+        module = import_path(
+            fn2, mode="importlib", root=tmp_path, consider_namespace_packages=False
+        )
         Data2 = getattr(module, "Data")
 
         assert round_trip(Data1(20)) == Data1(20)
@@ -635,7 +702,7 @@ class TestImportLibMode:
         # If we add tmp_path to sys.path, src becomes a namespace package.
         monkeypatch.syspath_prepend(tmp_path)
         assert resolve_pkg_root_and_module_name(
-            models_py, consider_ns_packages=True
+            models_py, consider_namespace_packages=True
         ) == (
             tmp_path,
             "src.app.core.models",
@@ -709,7 +776,12 @@ class TestImportLibMode:
             encoding="ascii",
         )
 
-        mod = import_path(init, root=tmp_path, mode=ImportMode.importlib)
+        mod = import_path(
+            init,
+            root=tmp_path,
+            mode=ImportMode.importlib,
+            consider_namespace_packages=False,
+        )
         assert len(mod.instance.INSTANCES) == 1
 
     def test_importlib_root_is_package(self, pytester: Pytester) -> None:
@@ -828,16 +900,31 @@ class TestImportLibMode:
         )
 
         # core_py is reached from sys.path, so should be imported normally.
-        mod = import_path(core_py, mode="importlib", root=pytester.path)
+        mod = import_path(
+            core_py,
+            mode="importlib",
+            root=pytester.path,
+            consider_namespace_packages=False,
+        )
         assert mod.__name__ == "app.core"
         assert mod.__file__ and Path(mod.__file__) == core_py
 
         # tests are not reachable from sys.path, so they are imported as a standalone modules.
         # Instead of '.tests.a.test_core', we import as "_tests.a.test_core" because
         # importlib considers module names starting with '.' to be local imports.
-        mod = import_path(test_path1, mode="importlib", root=pytester.path)
+        mod = import_path(
+            test_path1,
+            mode="importlib",
+            root=pytester.path,
+            consider_namespace_packages=False,
+        )
         assert mod.__name__ == "_tests.a.test_core"
-        mod = import_path(test_path2, mode="importlib", root=pytester.path)
+        mod = import_path(
+            test_path2,
+            mode="importlib",
+            root=pytester.path,
+            consider_namespace_packages=False,
+        )
         assert mod.__name__ == "_tests.b.test_core"
 
     def test_import_using_normal_mechanism_first_integration(
@@ -889,14 +976,22 @@ class TestImportLibMode:
         # The 'x.py' module from sys.path was not imported for sure because
         # otherwise we would get an AssertionError.
         mod = import_path(
-            x_in_sub_folder, mode=ImportMode.importlib, root=pytester.path
+            x_in_sub_folder,
+            mode=ImportMode.importlib,
+            root=pytester.path,
+            consider_namespace_packages=False,
         )
         assert mod.__file__ and Path(mod.__file__) == x_in_sub_folder
         assert mod.X == "a/b/x"
 
         # Attempt to import root 'x.py'.
         with pytest.raises(AssertionError, match="x at root"):
-            _ = import_path(x_at_root, mode=ImportMode.importlib, root=pytester.path)
+            _ = import_path(
+                x_at_root,
+                mode=ImportMode.importlib,
+                root=pytester.path,
+                consider_namespace_packages=False,
+            )
 
 
 def test_safe_exists(tmp_path: Path) -> None:
@@ -979,26 +1074,33 @@ class TestNamespacePackages:
         )
 
         pkg_root, module_name = resolve_pkg_root_and_module_name(
-            models_py, consider_ns_packages=True
+            models_py, consider_namespace_packages=True
         )
         assert (pkg_root, module_name) == (
             tmp_path / "src/dist1",
             "com.company.app.core.models",
         )
 
-        mod = import_path(models_py, mode=import_mode, root=tmp_path)
+        mod = import_path(
+            models_py, mode=import_mode, root=tmp_path, consider_namespace_packages=True
+        )
         assert mod.__name__ == "com.company.app.core.models"
         assert mod.__file__ == str(models_py)
 
         pkg_root, module_name = resolve_pkg_root_and_module_name(
-            algorithms_py, consider_ns_packages=True
+            algorithms_py, consider_namespace_packages=True
         )
         assert (pkg_root, module_name) == (
             tmp_path / "src/dist2",
             "com.company.calc.algo.algorithms",
         )
 
-        mod = import_path(algorithms_py, mode=import_mode, root=tmp_path)
+        mod = import_path(
+            algorithms_py,
+            mode=import_mode,
+            root=tmp_path,
+            consider_namespace_packages=True,
+        )
         assert mod.__name__ == "com.company.calc.algo.algorithms"
         assert mod.__file__ == str(algorithms_py)
 
@@ -1019,7 +1121,7 @@ class TestNamespacePackages:
         (tmp_path / "src/dist1/com/__init__.py").touch()
 
         pkg_root, module_name = resolve_pkg_root_and_module_name(
-            models_py, consider_ns_packages=True
+            models_py, consider_namespace_packages=True
         )
         assert (pkg_root, module_name) == (
             tmp_path / "src/dist1/com/company",

testing/test_pluginmanager.py

@@ -46,7 +46,10 @@ class TestPytestPluginInteractions:
             kwargs=dict(pluginmanager=config.pluginmanager)
         )
         config.pluginmanager._importconftest(
-            conf, importmode="prepend", rootpath=pytester.path
+            conf,
+            importmode="prepend",
+            rootpath=pytester.path,
+            consider_namespace_packages=False,
         )
         # print(config.pluginmanager.get_plugins())
         res = config.hook.pytest_myhook(xyz=10)
@@ -75,7 +78,10 @@ class TestPytestPluginInteractions:
         """
         )
         config.pluginmanager._importconftest(
-            p, importmode="prepend", rootpath=pytester.path
+            p,
+            importmode="prepend",
+            rootpath=pytester.path,
+            consider_namespace_packages=False,
         )
         assert config.option.test123
 
@@ -115,6 +121,7 @@ class TestPytestPluginInteractions:
             conftest,
             importmode="prepend",
             rootpath=pytester.path,
+            consider_namespace_packages=False,
         )
         plugin = config.pluginmanager.get_plugin(str(conftest))
         assert plugin is mod
@@ -123,6 +130,7 @@ class TestPytestPluginInteractions:
             conftest_upper_case,
             importmode="prepend",
             rootpath=pytester.path,
+            consider_namespace_packages=False,
         )
         plugin_uppercase = config.pluginmanager.get_plugin(str(conftest_upper_case))
         assert plugin_uppercase is mod_uppercase
@@ -174,12 +182,18 @@ class TestPytestPluginInteractions:
         conftest2 = pytester.path.joinpath("tests/subdir/conftest.py")
 
         config.pluginmanager._importconftest(
-            conftest1, importmode="prepend", rootpath=pytester.path
+            conftest1,
+            importmode="prepend",
+            rootpath=pytester.path,
+            consider_namespace_packages=False,
         )
         ihook_a = session.gethookproxy(pytester.path / "tests")
         assert ihook_a is not None
         config.pluginmanager._importconftest(
-            conftest2, importmode="prepend", rootpath=pytester.path
+            conftest2,
+            importmode="prepend",
+            rootpath=pytester.path,
+            consider_namespace_packages=False,
         )
         ihook_b = session.gethookproxy(pytester.path / "tests")
         assert ihook_a is not ihook_b
@@ -398,7 +412,9 @@ class TestPytestPluginManager:
         pytestpm: PytestPluginManager,
     ) -> None:
         mod = import_path(
-            pytester.makepyfile("pytest_plugins='xyz'"), root=pytester.path
+            pytester.makepyfile("pytest_plugins='xyz'"),
+            root=pytester.path,
+            consider_namespace_packages=False,
         )
         with pytest.raises(ImportError):
             pytestpm.consider_conftest(mod, registration_name="unused")