[PATCH 6 of 9] add a function to calculate the branch heads that will be closed

[Alexis S. L. Carvalho]

# HG changeset patch
# User Alexis S. L. Carvalho <alexis at cecm.usp.br>
# Date 1204481759 10800
# Node ID 09195d7818674502a33a74060ac41e58092c6a50
# Parent  cd038204b2f47831131a5b28cee6c5864605aa30
add a function to calculate the branch heads that will be closed

diff -r cd038204b2f4 -r 09195d781867 mercurial/localrepo.py
--- a/mercurial/localrepo.py	Sun Mar 02 15:15:59 2008 -0300
+++ b/mercurial/localrepo.py	Sun Mar 02 15:15:59 2008 -0300
@@ -721,6 +721,46 @@ class localrepository(repo.repository):
                        self.origroot)
         self._wlockref = weakref.ref(l)
         return l
+
+    def closebranchnodes(self, name, parents):
+        """
+        returns the heads of branch name that are ancestors of one of the
+        parents
+        """
+        branches = self.branchtags()
+        if name not in branches:
+            raise repo.RepoError(_("there's no branch named %s") % name)
+        heads = branches[name]
+        parents = [p for p in parents if p != nullid]
+
+        # The easy common case: see if the heads we want to close
+        # are in parents
+        close = [p for p in parents if p in heads]
+        if len(close) == len(heads) or len(close) == len(parents):
+            # either all the heads of the branch were in parents,
+            # or all parents were heads of the branch
+            return close
+
+        # Handle the more general case: see if one or more of the remaining
+        # heads are ancestors of one of the remaining parents
+        cl = self.changelog
+        parents = [cl.rev(p) for p in parents if p not in close]
+        heads = dict.fromkeys([cl.rev(n) for n in branches[name]
+                               if n not in close])
+        ancestors = dict.fromkeys(parents)
+        for r in xrange(max(parents), min(heads) - 1, -1):
+            if r in ancestors:
+                if r in heads:
+                    close.append(cl.node(r))
+                    # no need to put parentrevs(r) in ancestor
+                    # since the other heads are not ancestors of r
+                else:
+                    for p in cl.parentrevs(r):
+                        if p != nullrev:
+                            ancestors[p] = 1
+                del ancestors[r]
+
+        return close
 
     def filecommit(self, fn, manifest1, manifest2, linkrev, tr, changelist):
         """