tests(module_loading): Port tests from django 4.0 w/ touchups

tony · tony · commit a3a63b547a12 · 2022-04-30T04:17:07.000-05:00
Remove django-specific stuff so they're generic. Use pytest for sys paths. See also: https://github.com/django/django/blob/4.0.4/django/utils/module_loading.py
diff --git a/tests/utils/__init__.py b/tests/utils/__init__.py
diff --git a/tests/utils/test_module/__init__.py b/tests/utils/test_module/__init__.py
@@ -0,0 +1,5 @@
+class SiteMock:
+    _registry = {}
+
+
+site = SiteMock()
diff --git a/tests/utils/test_module/__main__.py b/tests/utils/test_module/__main__.py
diff --git a/tests/utils/test_module/another_bad_module.py b/tests/utils/test_module/another_bad_module.py
@@ -0,0 +1,11 @@
+from . import site
+
+content = "Another Bad Module"
+
+site._registry.update(
+    {
+        "foo": "bar",
+    }
+)
+
+raise Exception("Some random exception.")
diff --git a/tests/utils/test_module/another_good_module.py b/tests/utils/test_module/another_good_module.py
@@ -0,0 +1,9 @@
+from . import site
+
+content = "Another Good Module"
+
+site._registry.update(
+    {
+        "lorem": "ipsum",
+    }
+)
diff --git a/tests/utils/test_module/bad_module.py b/tests/utils/test_module/bad_module.py
@@ -0,0 +1,3 @@
+import a_package_name_that_does_not_exist  # NOQA
+
+content = "Bad Module"
diff --git a/tests/utils/test_module/child_module/__init__.py b/tests/utils/test_module/child_module/__init__.py
diff --git a/tests/utils/test_module/child_module/grandchild_module.py b/tests/utils/test_module/child_module/grandchild_module.py
@@ -0,0 +1 @@
+content = "Grandchild Module"
diff --git a/tests/utils/test_module/good_module.py b/tests/utils/test_module/good_module.py
@@ -0,0 +1 @@
+content = "Good Module"
diff --git a/tests/utils/test_module/main_module.py b/tests/utils/test_module/main_module.py
diff --git a/tests/utils/test_module_loading.py b/tests/utils/test_module_loading.py
@@ -0,0 +1,146 @@
+"""
+Credit: https://github.com/django/django/blob/4.0.4/tests/utils_tests/test_module_loading.py
+
+From April 25th, 2021. Changes:
+
+- pytest compatibility, use monkeypatch.syspath_prepend
+- Removed django-specific material
+"""  # noqa: E501
+import os
+import sys
+import unittest
+from importlib import import_module
+
+import pytest
+
+from libvcs.utils.module_loading import import_string, module_has_submodule
+
+PY310 = sys.version_info >= (3, 10)
+
+
+class DefaultLoader(unittest.TestCase):
+    def test_loader(self):
+        "Normal module existence can be tested"
+        test_module = import_module("tests.utils.test_module")
+        test_no_submodule = import_module("tests.utils.test_no_submodule")
+
+        # An importable child
+        self.assertTrue(module_has_submodule(test_module, "good_module"))
+        mod = import_module("tests.utils.test_module.good_module")
+        self.assertEqual(mod.content, "Good Module")
+
+        # A child that exists, but will generate an import error if loaded
+        self.assertTrue(module_has_submodule(test_module, "bad_module"))
+        with self.assertRaises(ImportError):
+            import_module("tests.utils.test_module.bad_module")
+
+        # A child that doesn't exist
+        self.assertFalse(module_has_submodule(test_module, "no_such_module"))
+        with self.assertRaises(ImportError):
+            import_module("tests.utils.test_module.no_such_module")
+
+        # A child that doesn't exist, but is the name of a package on the path
+        self.assertFalse(module_has_submodule(test_module, "django"))
+        with self.assertRaises(ImportError):
+            import_module("tests.utils.test_module.django")
+
+        # Don't be confused by caching of import misses
+        import types  # NOQA: causes attempted import of tests.utils.types
+
+        self.assertFalse(module_has_submodule(sys.modules["tests.utils"], "types"))
+
+        # A module which doesn't have a __path__ (so no submodules)
+        self.assertFalse(module_has_submodule(test_no_submodule, "anything"))
+        with self.assertRaises(ImportError):
+            import_module("tests.utils.test_no_submodule.anything")
+
+    def test_has_sumbodule_with_dotted_path(self):
+        """Nested module existence can be tested."""
+        test_module = import_module("tests.utils.test_module")
+        # A grandchild that exists.
+        self.assertIs(
+            module_has_submodule(test_module, "child_module.grandchild_module"), True
+        )
+        # A grandchild that doesn't exist.
+        self.assertIs(
+            module_has_submodule(test_module, "child_module.no_such_module"), False
+        )
+        # A grandchild whose parent doesn't exist.
+        self.assertIs(
+            module_has_submodule(test_module, "no_such_module.grandchild_module"), False
+        )
+        # A grandchild whose parent is not a package.
+        self.assertIs(
+            module_has_submodule(test_module, "good_module.no_such_module"), False
+        )
+
+
+class EggLoader:
+    def setUp(self):
+        self.egg_dir = "%s/eggs" % os.path.dirname(__file__)
+
+    def tearDown(self):
+        sys.path_importer_cache.clear()
+
+        sys.modules.pop("egg_module.sub1.sub2.bad_module", None)
+        sys.modules.pop("egg_module.sub1.sub2.good_module", None)
+        sys.modules.pop("egg_module.sub1.sub2", None)
+        sys.modules.pop("egg_module.sub1", None)
+        sys.modules.pop("egg_module.bad_module", None)
+        sys.modules.pop("egg_module.good_module", None)
+        sys.modules.pop("egg_module", None)
+
+    def test_shallow_loader(self, monkeypatch: pytest.MonkeyPatch):
+        "Module existence can be tested inside eggs"
+        egg_name = "%s/test_egg.egg" % self.egg_dir
+        monkeypatch.syspath_prepend(egg_name)
+        egg_module = import_module("egg_module")
+
+        # An importable child
+        self.assertTrue(module_has_submodule(egg_module, "good_module"))
+        mod = import_module("egg_module.good_module")
+        self.assertEqual(mod.content, "Good Module")
+
+        # A child that exists, but will generate an import error if loaded
+        self.assertTrue(module_has_submodule(egg_module, "bad_module"))
+        with self.assertRaises(ImportError):
+            import_module("egg_module.bad_module")
+
+        # A child that doesn't exist
+        self.assertFalse(module_has_submodule(egg_module, "no_such_module"))
+        with self.assertRaises(ImportError):
+            import_module("egg_module.no_such_module")
+
+    def test_deep_loader(self, monkeypatch: pytest.MonkeyPatch):
+        "Modules deep inside an egg can still be tested for existence"
+        egg_name = "%s/test_egg.egg" % self.egg_dir
+        monkeypatch.syspath_prepend(egg_name)
+        egg_module = import_module("egg_module.sub1.sub2")
+
+        # An importable child
+        self.assertTrue(module_has_submodule(egg_module, "good_module"))
+        mod = import_module("egg_module.sub1.sub2.good_module")
+        self.assertEqual(mod.content, "Deep Good Module")
+
+        # A child that exists, but will generate an import error if loaded
+        self.assertTrue(module_has_submodule(egg_module, "bad_module"))
+        with self.assertRaises(ImportError):
+            import_module("egg_module.sub1.sub2.bad_module")
+
+        # A child that doesn't exist
+        self.assertFalse(module_has_submodule(egg_module, "no_such_module"))
+        with self.assertRaises(ImportError):
+            import_module("egg_module.sub1.sub2.no_such_module")
+
+
+class ModuleImportTests:
+    def test_import_string(self):
+        cls = import_string("libvcs.utils.module_loading.import_string")
+        self.assertEqual(cls, import_string)
+
+        # Test exceptions raised
+        with self.assertRaises(ImportError):
+            import_string("no_dots_in_path")
+        msg = 'Module "tests.utils" does not define a "unexistent" attribute'
+        with self.assertRaisesMessage(ImportError, msg):
+            import_string("tests.utils.unexistent")
diff --git a/tests/utils/test_no_submodule.py b/tests/utils/test_no_submodule.py
@@ -0,0 +1 @@
+# Used to test for modules which don't have submodules.

Original file line number	Diff line number	Diff line change
`@@ -0,0 +1,3 @@`
	`1`	`+import a_package_name_that_does_not_exist # NOQA`
	`2`	`+`
	`3`	`+content = "Bad Module"`