When test passes and we're preparing to merge, note that

Particularly in fast forward situations, we can have just one comment
that includes the successful test result and note that we're preparing
to merge, including a link to the merged checksum.

homu/server.py

@@ -406,9 +406,11 @@ def report_build_res(succ, url, builder, state, logger, repo_cfg):
             utils.github_create_status(state.get_repo(), state.head_sha, 'success', url, desc, context='homu')
 
             urls = ', '.join('[{}]({})'.format(builder, x['url']) for builder, x in sorted(state.build_res.items()))
-            state.add_comment(':sunny: {} - {}'.format(desc, urls))
+            test_comment = ':sunny: {} - {}'.format(desc, urls)
 
             if state.approved_by and not state.try_:
+                comment = test_comment + '\n' + 'Approved by={}\nPerforming merge as {}...'.format(state.approved_by, state.merge_sha)
+                state.add_comment(comment)
                 try:
                     try: utils.github_set_ref(state.get_repo(), 'heads/' + state.base_ref, state.merge_sha)
                     except github3.models.GitHubError:
@@ -423,6 +425,9 @@ def report_build_res(succ, url, builder, state, logger, repo_cfg):
                     utils.github_create_status(state.get_repo(), state.head_sha, 'error', url, desc, context='homu')
 
                     state.add_comment(':eyes: ' + desc)
+            else:
+                comment = test_comment + '\n' + 'State: approved={} try={}'.format(state.approved_by, state.try_)
+                state.add_comment(comment)
 
     else:
         if state.status == 'pending':