diff --git a/endpoints/trigger.py b/endpoints/trigger.py
index 4c476533c..2bcdc6242 100644
--- a/endpoints/trigger.py
+++ b/endpoints/trigger.py
@@ -488,30 +488,36 @@ class BitbucketBuildTrigger(BuildTriggerHandler):
     # Parse the JSON payload.
     payload_json = request.form.get('payload')
     if not payload_json:
+      logger.debug('Skipping BitBucket request due to missing payload')
       raise SkipRequestException()
 
     try:
       payload = json.loads(payload_json)
     except ValueError:
+      logger.debug('Skipping BitBucket request due to invalid payload')
       raise SkipRequestException()
 
     logger.debug('BitBucket trigger payload %s', payload)
 
     # Make sure we have a commit in the payload.
     if not payload.get('commits'):
+      logger.debug('Skipping BitBucket request due to missing commits block')
       raise SkipRequestException()
 
     # Check if this build should be skipped by commit message.
     commit = payload['commits'][0]
     commit_message = commit['message']
     if should_skip_commit(commit_message):
+      logger.debug('Skipping BitBucket request due to commit message request')
       raise SkipRequestException()
 
     # Check to see if this build should be skipped by ref.
     if not commit.get('branch') and not commit.get('tag'):
+      logger.debug('Skipping BitBucket request due to missing branch and tag')
       raise SkipRequestException()
 
     ref = 'refs/heads/' + commit['branch'] if commit.get('branch') else 'refs/tags/' + commit['tag']
+    logger.debug('Checking BitBucket request: %s', ref)
     raise_if_skipped(self.config, ref)
 
     commit_sha = commit['node']
diff --git a/test/test_trigger.py b/test/test_trigger.py
new file mode 100644
index 000000000..d01853d96
--- /dev/null
+++ b/test/test_trigger.py
@@ -0,0 +1,29 @@
+import unittest
+import re
+
+from endpoints.trigger import matches_ref
+
+class TestRegex(unittest.TestCase):
+  def assertDoesNotMatch(self, ref, filt):
+    self.assertFalse(matches_ref(ref, re.compile(filt)))
+
+  def assertMatches(self, ref, filt):
+    self.assertTrue(matches_ref(ref, re.compile(filt)))
+
+  def test_matches_ref(self):
+    self.assertMatches('ref/heads/master', '.+')
+    self.assertMatches('ref/heads/master', 'heads/.+')
+    self.assertMatches('ref/heads/master', 'heads/master')
+
+    self.assertDoesNotMatch('ref/heads/foobar', 'heads/master')
+    self.assertDoesNotMatch('ref/heads/master', 'tags/master')
+
+    self.assertMatches('ref/heads/master', '(((heads/alpha)|(heads/beta))|(heads/gamma))|(heads/master)')
+    self.assertMatches('ref/heads/alpha', '(((heads/alpha)|(heads/beta))|(heads/gamma))|(heads/master)')
+    self.assertMatches('ref/heads/beta', '(((heads/alpha)|(heads/beta))|(heads/gamma))|(heads/master)')
+    self.assertMatches('ref/heads/gamma', '(((heads/alpha)|(heads/beta))|(heads/gamma))|(heads/master)')
+
+    self.assertDoesNotMatch('ref/heads/delta', '(((heads/alpha)|(heads/beta))|(heads/gamma))|(heads/master)')
+
+if __name__ == '__main__':
+  unittest.main()