diff --git a/contrib/python3-whitelist b/contrib/python3-whitelist
--- a/contrib/python3-whitelist
+++ b/contrib/python3-whitelist
@@ -301,6 +301,7 @@
 test-minifileset.py
 test-minirst.py
 test-mq-git.t
+test-mq-guards.t
 test-mq-header-date.t
 test-mq-header-from.t
 test-mq-merge.t
@@ -313,6 +314,7 @@
 test-mq-qimport-fail-cleanup.t
 test-mq-qnew.t
 test-mq-qpush-exact.t
+test-mq-qpush-fail.t
 test-mq-qqueue.t
 test-mq-qrefresh-interactive.t
 test-mq-qrefresh-replace-log-message.t
diff --git a/hgext/mq.py b/hgext/mq.py
--- a/hgext/mq.py
+++ b/hgext/mq.py
@@ -662,13 +662,13 @@
         exactneg = [g for g in patchguards
                     if g.startswith('-') and g[1:] in guards]
         if exactneg:
-            return False, pycompat.byterepr(exactneg[0])
+            return False, stringutil.pprint(exactneg[0])
         pos = [g for g in patchguards if g.startswith('+')]
         exactpos = [g for g in pos if g[1:] in guards]
         if pos:
             if exactpos:
-                return True, pycompat.byterepr(exactpos[0])
-            return False, ' '.join([pycompat.byterepr(p) for p in pos])
+                return True, stringutil.pprint(exactpos[0])
+            return False, ' '.join([stringutil.pprint(p) for p in pos])
         return True, ''
 
     def explainpushable(self, idx, all_patches=False):