Merge #1715

Crash of bindctl when the config unset command was invoked. The code of
the command was missing, probably never implemented and obviously never
tested.

src/bin/bindctl/tests/bindctl_test.py

@@ -365,10 +365,20 @@ class TestConfigCommands(unittest.TestCase):
         self.assertEqual((5, MultiConfigData.LOCAL),
                          self.tool.config_data.get_value("/foo/an_int"))
 
+        cmd = cmdparse.BindCmdParse("config unset identifier=\"foo/an_int\"")
+        self.tool.apply_config_cmd(cmd)
+
+        self.assertEqual((1, MultiConfigData.DEFAULT),
+                         self.tool.config_data.get_value("/foo/an_int"))
+
         # this should raise a NotFoundError
         cmd = cmdparse.BindCmdParse("config set identifier=\"foo/bar\" value=\"[]\"")
         self.assertRaises(isc.cc.data.DataNotFoundError, self.tool.apply_config_cmd, cmd)
 
+        cmd = cmdparse.BindCmdParse("config unset identifier=\"foo/bar\"")
+        self.assertRaises(isc.cc.data.DataNotFoundError,
+                          self.tool.apply_config_cmd, cmd)
+
         # this should raise a TypeError
         cmd = cmdparse.BindCmdParse("config set identifier=\"foo/an_int\" value=\"[]\"")
         self.assertRaises(isc.cc.data.DataTypeError, self.tool.apply_config_cmd, cmd)

src/lib/python/isc/config/config_data.py

@@ -672,6 +672,16 @@ class MultiConfigData:
                 self._append_value_item(result, spec_part, identifier, all, True)
         return result
 
+    def unset(self, identifier):
+        """
+        Reset the value to default.
+        """
+        spec_part = self.find_spec_part(identifier)
+        if spec_part is not None:
+            isc.cc.data.unset(self._local_changes, identifier)
+        else:
+            raise isc.cc.data.DataNotFoundError(identifier + "not found")
+
     def set_value(self, identifier, value):
         """Set the local value at the given identifier to value. If
            there is a specification for the given identifier, the type

src/lib/python/isc/config/tests/config_data_test.py

@@ -657,7 +657,38 @@ class TestMultiConfigData(unittest.TestCase):
         self.assertEqual(MultiConfigData.LOCAL, status)
 
         self.assertRaises(isc.cc.data.DataTypeError, self.mcd.set_value, "Spec2/item5[a]", "asdf")
-        
+
+
+    def test_unset(self):
+        """
+        Test the unset command works.
+        """
+        module_spec = isc.config.module_spec_from_file(self.data_path + os.sep + "spec2.spec")
+        self.mcd.set_specification(module_spec)
+        self.mcd.set_specification(module_spec)
+        value, status = self.mcd.get_value("Spec2/item1")
+        # This is the default first
+        self.assertEqual(1, value)
+        self.assertEqual(MultiConfigData.DEFAULT, status)
+        # Unseting a default item does nothing.
+        self.mcd.unset("Spec2/item1")
+        value, status = self.mcd.get_value("Spec2/item1")
+        # This should be the default
+        self.assertEqual(1, value)
+        self.assertEqual(MultiConfigData.DEFAULT, status)
+        # Set it to something else
+        self.mcd.set_value("Spec2/item1", 42)
+        value, status = self.mcd.get_value("Spec2/item1")
+        self.assertEqual(42, value)
+        self.assertEqual(MultiConfigData.LOCAL, status)
+        # Try to unset it
+        self.mcd.unset("Spec2/item1")
+        value, status = self.mcd.get_value("Spec2/item1")
+        # This should be the default
+        self.assertEqual(1, value)
+        self.assertEqual(MultiConfigData.DEFAULT, status)
+        # Unset a nonexisting item. Should raise.
+        self.assertRaises(isc.cc.data.DataNotFoundError, self.mcd.unset, "Spec2/doesnotexist")
 
     def test_get_config_item_list(self):
         config_items = self.mcd.get_config_item_list()