1 files changed, 52 insertions, 0 deletions
diff --git a/Lib/importlib/test/builtin/test_loader.py b/Lib/importlib/test/builtin/test_loader.py
new file mode 100644
index 0000000..5aa3d79
--- /dev/null
+++ b/Lib/importlib/test/builtin/test_loader.py
@@ -0,0 +1,52 @@
+import importlib
+from .. import support
+
+import sys
+import types
+import unittest
+
+
+class LoaderTests(unittest.TestCase):
+
+    """Test load_module() for built-in modules."""
+
+    assert 'errno' in sys.builtin_module_names
+    name = 'errno'
+
+    verification = {'__name__': 'errno', '__package__': None}
+
+    def verify(self, module):
+        """Verify that the module matches against what it should have."""
+        self.assert_(isinstance(module, types.ModuleType))
+        for attr, value in self.verification.items():
+            self.assertEqual(getattr(module, attr), value)
+        self.assert_(module.__name__ in sys.modules)
+
+    load_module = staticmethod(lambda name:
+                                importlib.BuiltinImporter().load_module(name))
+
+    def test_load_module(self):
+        # Common case.
+        with support.uncache(self.name):
+            module = self.load_module(self.name)
+            self.verify(module)
+
+    def test_nonexistent(self):
+        name = 'dssdsdfff'
+        assert name not in sys.builtin_module_names
+        self.assertRaises(ImportError, self.load_module, name)
+
+    def test_already_imported(self):
+        # Using the name of a module already imported but not a built-in should
+        # still fail.
+        assert hasattr(importlib, '__file__')  # Not a built-in.
+        self.assertRaises(ImportError, self.load_module, 'importlib')
+
+
+def test_main():
+    from test.support import run_unittest
+    run_unittest(LoaderTests)
+
+
+if __name__ == '__main__':
+    test_main()