--- a/mercurial/localrepo.py	Sat Nov 29 19:13:35 2014 -0800
+++ b/mercurial/localrepo.py	Sat Nov 29 19:17:47 2014 -0800
@@ -1754,8 +1754,14 @@
         return ret
 
     def pushkey(self, namespace, key, old, new):
-        self.hook('prepushkey', throw=True, namespace=namespace, key=key,
-                  old=old, new=new)
+        try:
+            self.hook('prepushkey', throw=True, namespace=namespace, key=key,
+                      old=old, new=new)
+        except error.HookAbort, exc:
+            self.ui.write_err(_("pushkey-abort: %s\n") % exc)
+            if exc.hint:
+                self.ui.write_err(_("(%s)\n") % exc.hint)
+            return False
         self.ui.debug('pushing key for "%s:%s"\n' % (namespace, key))
         ret = pushkey.push(self, namespace, key, old, new)
         self.hook('pushkey', namespace=namespace, key=key, old=old, new=new,

--- a/tests/test-bookmarks-pushpull.t	Sat Nov 29 19:13:35 2014 -0800
+++ b/tests/test-bookmarks-pushpull.t	Sat Nov 29 19:17:47 2014 -0800
@@ -486,4 +486,77 @@
   no changes found
   [1]
 
-  $ cd ..
+
+Check hook preventing push (issue4455)
+======================================
+
+  $ hg bookmarks
+   * @                         0:55482a6fb4b1
+  $ hg log -G
+  @  0:55482a6fb4b1 initial
+  
+  $ hg init ../issue4455-dest
+  $ hg push ../issue4455-dest # changesets only
+  pushing to ../issue4455-dest
+  searching for changes
+  adding changesets
+  adding manifests
+  adding file changes
+  added 1 changesets with 1 changes to 1 files
+  $ cat >> .hg/hgrc << EOF
+  > [paths]
+  > local=../issue4455-dest/
+  > ssh=ssh://user@dummy/issue4455-dest
+  > http=http://localhost:$HGPORT/
+  > [ui]
+  > ssh=python "$TESTDIR/dummyssh"
+  > EOF
+  $ cat >> ../issue4455-dest/.hg/hgrc << EOF
+  > [hooks]
+  > prepushkey=false
+  > [web]
+  > push_ssl = false
+  > allow_push = *
+  > EOF
+  $ "$TESTDIR/killdaemons.py" $DAEMON_PIDS
+  $ hg -R ../issue4455-dest serve -p $HGPORT -d --pid-file=../issue4455.pid -E ../issue4455-error.log
+  $ cat ../issue4455.pid >> $DAEMON_PIDS
+
+Local push
+----------
+
+  $ hg push -B @ local
+  pushing to $TESTTMP/issue4455-dest (glob)
+  searching for changes
+  no changes found
+  pushkey-abort: prepushkey hook exited with status 1
+  exporting bookmark @ failed!
+  [1]
+  $ hg -R ../issue4455-dest/ bookmarks
+  no bookmarks set
+
+Using ssh
+---------
+
+  $ hg push -B @ ssh
+  pushing to ssh://user@dummy/issue4455-dest
+  searching for changes
+  no changes found
+  remote: pushkey-abort: prepushkey hook exited with status 1
+  exporting bookmark @ failed!
+  [1]
+  $ hg -R ../issue4455-dest/ bookmarks
+  no bookmarks set
+
+Using http
+----------
+
+  $ hg push -B @ http
+  pushing to http://localhost:$HGPORT/
+  searching for changes
+  no changes found
+  remote: pushkey-abort: prepushkey hook exited with status 1
+  exporting bookmark @ failed!
+  [1]
+  $ hg -R ../issue4455-dest/ bookmarks
+  no bookmarks set

--- a/tests/test-hook.t	Sat Nov 29 19:13:35 2014 -0800
+++ b/tests/test-hook.t	Sat Nov 29 19:17:47 2014 -0800
@@ -215,8 +215,9 @@
   no changes found
   listkeys hook: HG_NAMESPACE=phases HG_VALUES={'cb9a9f314b8b07ba71012fcdbc544b5a4d82ff5b': '1', 'publishing': 'True'}
   prepushkey.forbid hook: HG_KEY=baz HG_NAMESPACE=bookmarks HG_NEW=0000000000000000000000000000000000000000
-  abort: prepushkey hook exited with status 1
-  [255]
+  pushkey-abort: prepushkey hook exited with status 1
+  exporting bookmark baz failed!
+  [1]
   $ cd ../a
 
 test that prelistkeys can prevent listing keys

--- a/tests/test-ssh.t	Sat Nov 29 19:13:35 2014 -0800
+++ b/tests/test-ssh.t	Sat Nov 29 19:17:47 2014 -0800
@@ -392,9 +392,9 @@
   remote: Permission denied
   remote: abort: prechangegroup.hg-ssh hook failed
   remote: Permission denied
-  remote: abort: prepushkey.hg-ssh hook failed
-  abort: unexpected response: empty string
-  [255]
+  remote: pushkey-abort: prepushkey.hg-ssh hook failed
+  updating 6c0482d977a3 to public failed!
+  [1]
 
   $ cd ..