Don't get confused by namespace packages #456

1 files changed, 21 insertions, 0 deletions

diff --git a/tests/test_api.py b/tests/test_api.py
index 3ea5b3ef..4c038519 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -9,6 +9,7 @@ import sys
 import textwrap
 
 import coverage
+from coverage import env
 from coverage.backward import StringIO
 from coverage.misc import CoverageException
 
@@ -322,6 +323,26 @@ class ApiTest(CoverageTest):
         self.assert_exists(".coverage.foo")
 
 
+class NamespaceModuleTest(CoverageTest):
+    """Test PEP-420 namespace modules."""
+
+    def setUp(self):
+        super(NamespaceModuleTest, self).setUp()
+        if env.PYVERSION < (3, 3):
+            self.skip("Python before 3.3 doesn't have namespace packages")
+
+    def test_explicit_namespace_module(self):
+        self.make_file("namespace/package/module.py", "VAR = 1\n")
+        self.make_file("main.py", "import namespace\n")
+
+        cov = coverage.Coverage()
+        self.start_import_stop(cov, "main")
+
+        with self.assertRaisesRegex(CoverageException, r"Module .* has no file"):
+            cov.analysis(sys.modules['namespace'])
+
+
+
 class UsingModulesMixin(object):
     """A mixin for importing modules from test/modules and test/moremodules."""