Merge. Closes issue 17052.

1 files changed, 14 insertions, 0 deletions

diff --git a/Lib/unittest/test/test_discovery.py b/Lib/unittest/test/test_discovery.py
index e688f8e..eba269f 100644
--- a/Lib/unittest/test/test_discovery.py
+++ b/Lib/unittest/test/test_discovery.py
@@ -253,12 +253,26 @@ class TestDiscovery(unittest.TestCase):
 
         program = TestableTestProgram()
         program.usageExit = usageExit
+        program.testLoader = None
 
         with self.assertRaises(Stop):
             # too many args
             program._do_discovery(['one', 'two', 'three', 'four'])
 
 
+    def test_command_line_handling_do_discovery_uses_default_loader(self):
+        program = object.__new__(unittest.TestProgram)
+
+        class Loader(object):
+            args = []
+            def discover(self, start_dir, pattern, top_level_dir):
+                self.args.append((start_dir, pattern, top_level_dir))
+                return 'tests'
+
+        program.testLoader = Loader
+        program._do_discovery(['-v'])
+        self.assertEqual(Loader.args, [('.', 'test*.py', None)])
+
     def test_command_line_handling_do_discovery_calls_loader(self):
         program = TestableTestProgram()