Fix ddev testable command to properly use the tag (and fallback on th…

…e branch if absent). (#4775)

datadog_checks_dev/datadog_checks/dev/tooling/commands/release.py

@@ -283,11 +283,14 @@ def testable(ctx, start_id, agent_version, milestone, dry_run):
     echo_info('Branch `{}` will be compared to `master`.'.format(current_release_branch))
 
     echo_waiting('Getting diff... ', nl=False)
-    diif_command = 'git --no-pager log "--pretty=format:%H %s" {}..master'
+    diff_command = 'git --no-pager log "--pretty=format:%H %s" {}..master'
 
     with chdir(root):
-        result = run_command(diif_command.format(current_release_branch), capture=True)
+        # compare with the local tag first
+        reftag = '{}{}'.format('refs/tags/', current_release_branch)
+        result = run_command(diff_command.format(reftag), capture=True)
         if result.code:
+            # if it didn't work, compare with a branch.
             origin_release_branch = 'origin/{}'.format(current_release_branch)
             echo_failure('failed!')
             echo_waiting(
@@ -297,9 +300,9 @@ def testable(ctx, start_id, agent_version, milestone, dry_run):
                 nl=False,
             )
 
-            result = run_command(diif_command.format(origin_release_branch), capture=True)
+            result = run_command(diff_command.format(origin_release_branch), capture=True)
             if result.code:
-                abort('Unable to get the diif.')
+                abort('Unable to get the diff.')
             else:
                 echo_success('success!')
         else: