Support tags for input args

Enable users to specify tags to be used to import and reference commits.

Change-Id: If2a9a2fa52d6c34ab110ae7a7fdbd02fae82e3b9
Closes-Bug: #1547180

git_upstream/lib/searchers.py

@@ -304,7 +304,7 @@ class UpstreamMergeBaseSearcher(LogDedentMixin, Searcher):
                 ["refs/remotes/*/{0}".format(ref) for ref in self.patterns])
 
         if search_tags:
-            self._references.append(
+            self._references.extend(
                 ["refs/tags/{0}".format(ref) for ref in self.patterns])
 
     @property

git_upstream/lib/strategies.py

@@ -116,8 +116,8 @@ class LocateChangesWalk(LocateChangesStrategy):
 
         super(LocateChangesWalk, self).__init__(*args, **kwargs)
 
-        self.searcher = UpstreamMergeBaseSearcher(branch=branch,
+        self.searcher = UpstreamMergeBaseSearcher(
-                                                  patterns=search_refs)
+            branch=branch, patterns=search_refs, search_tags=True)
 
     @property
     def previous_upstream(self):

git_upstream/tests/commands/import/test_import.py

@@ -101,6 +101,24 @@ class TestImportCommand(TestWithScenarios, BaseTestCase):
 
         self._check_tree_state()
 
+    def test_command_with_tags(self):
+        # add tag for each branch/ref and test with added tag
+        parser_args = []
+        for arg in self.parser_args:
+            if (arg.startswith('-') or arg in ("import",)):
+                parser_args.append(arg)
+                continue
+
+            tag_name = "tag-gu-%s" % arg.replace('~', '-')
+            self.git.tag(tag_name, arg)
+            parser_args.append(tag_name)
+
+        args = self.parser.parse_args(parser_args)
+        self.assertThat(args.cmd.run(args), Equals(True),
+                        "import command failed to complete successfully")
+
+        self._check_tree_state()
+
     def _check_tree_state(self):
 
         expected = getattr(self, 'expect_found', None)