--- a/mercurial/localrepo.py
+++ b/mercurial/localrepo.py
@@ -1345,6 +1345,9 @@ class localrepository(object):
 
         if not source:
             return
+
+        self.hook('prechangegroup', throw=True)
+
         changesets = files = revisions = 0
 
         tr = self.transaction()
@@ -1387,6 +1390,9 @@ class localrepository(object):
                          " with %d changes to %d files%s\n")
                          % (changesets, revisions, files, heads))
 
+        self.hook('pretxnchangegroup', throw=True,
+                  node=hex(self.changelog.node(cor+1)))
+
         tr.close()
 
         if changesets > 0: