Add ability to reset provider override

objects/providers.py

@@ -34,6 +34,10 @@ class Provider(object):
         """Override provider with another provider."""
         self.overridden.append(ensure_is_provider(provider))
 
+    def reset_override(self):
+        """Reset all overriding providers."""
+        self.overridden = list()
+
     @property
     def last_overriding(self):
         """Return last overriding provider."""

tests/test_providers.py

@@ -65,6 +65,25 @@ class ProviderTests(unittest.TestCase):
         """Test provider overriding with not provider instance."""
         self.assertRaises(Error, self.provider.override, object())
 
+    def test_reset_override(self):
+        """Test reset of provider's override."""
+        overriding_provider = Provider()
+        self.provider.override(overriding_provider)
+
+        self.assertTrue(self.provider.overridden)
+        self.assertIs(self.provider.last_overriding, overriding_provider)
+
+        self.provider.reset_override()
+
+        self.assertFalse(self.provider.overridden)
+        try:
+            self.provider.last_overriding
+        except Error:
+            pass
+        else:
+            self.fail('Got en error in {}'.format(
+                str(self.test_last_overriding_of_not_overridden_provider)))
+
     def test_last_overriding(self):
         """Test getting last overriding provider."""
         overriding_provider1 = Provider()