remote-helpers: improve marks usage

diff --git a/contrib/remote-helpers/git-remote-bzr b/contrib/remote-helpers/git-remote-bzr
index 10300c63d1a71aecd0f8d2273d276f36773e6b1e..f0e5be1d24ac12b9288f2d634363e9fa848e4ee0 100755 (executable)
--- a/contrib/remote-helpers/git-remote-bzr
+++ b/contrib/remote-helpers/git-remote-bzr
@@ -116,7 +116,10 @@ class Marks:
         self.last_mark = mark
 
     def get_tip(self, branch):
-        return self.tips.get(branch, None)
+        try:
+            return str(self.tips[branch])
+        except KeyError:
+            return None
 
     def set_tip(self, branch, tip):
         self.tips[branch] = tip