diff hgext/convert/cvsps.py @ 8756:6019e6517f95

convert: better support for CVS branchpoints (issue1447)

This records the branches starting at individual CVS file revisions,
using the symbolic names map rather than just the branches
information.  This information is used to generate Mercurial
changesets. Despite the changes, the CVS conversion still suffers
heavily from cvsps' deficiencies in generating a correct
representation of the CVS repository history.

--- a/hgext/convert/cvsps.py	Mon Jun 08 18:21:13 2009 -0500
+++ b/hgext/convert/cvsps.py	Tue Jun 09 08:59:49 2009 +0200
@@ -36,6 +36,7 @@
         .synthetic - is this a synthetic "file ... added on ..." revision?
         .mergepoint- the branch that has been merged from
                      (if present in rlog output)
+        .branchpoints- the branches that start at the current entry
     '''
     def __init__(self, **entries):
         self.__dict__.update(entries)
@@ -400,6 +401,19 @@
             else:
                 e.branch = None
 
+            # find the branches starting from this revision
+            branchpoints = set()
+            for branch, revision in branchmap.iteritems():
+                revparts = tuple([int(i) for i in revision.split('.')])
+                if revparts[-2] == 0 and revparts[-1] % 2 == 0:
+                    # normal branch
+                    if revparts[:-2] == e.revision:
+                        branchpoints.add(branch)
+                elif revparts == (1,1,1): # vendor branch
+                    if revparts in e.branches:
+                        branchpoints.add(branch)
+            e.branchpoints = branchpoints
+
             log.append(e)
 
             if len(log) % 100 == 0:
@@ -453,6 +467,7 @@
         .synthetic - from synthetic revision "file ... added on branch ..."
         .mergepoint- the branch that has been merged from
                      (if present in rlog output)
+        .branchpoints- the branches that start at the current entry
     '''
     def __init__(self, **entries):
         self.__dict__.update(entries)
@@ -477,17 +492,34 @@
     for i, e in enumerate(log):
 
         # Check if log entry belongs to the current changeset or not.
+
+        # Since CVS is file centric, two different file revisions with
+        # different branchpoints should be treated as belonging to two
+        # different changesets (and the ordering is important and not
+        # honoured by cvsps at this point).
+        #
+        # Consider the following case:
+        # foo 1.1 branchpoints: [MYBRANCH]
+        # bar 1.1 branchpoints: [MYBRANCH, MYBRANCH2]
+        #
+        # Here foo is part only of MYBRANCH, but not MYBRANCH2, e.g. a
+        # later version of foo may be in MYBRANCH2, so foo should be the
+        # first changeset and bar the next and MYBRANCH and MYBRANCH2
+        # should both start off of the bar changeset. No provisions are
+        # made to ensure that this is, in fact, what happens.
         if not (c and
                   e.comment == c.comment and
                   e.author == c.author and
                   e.branch == c.branch and
+                  e.branchpoints == c.branchpoints and
                   ((c.date[0] + c.date[1]) <=
                    (e.date[0] + e.date[1]) <=
                    (c.date[0] + c.date[1]) + fuzz) and
                   e.file not in files):
             c = changeset(comment=e.comment, author=e.author,
                           branch=e.branch, date=e.date, entries=[],
-                          mergepoint=getattr(e, 'mergepoint', None))
+                          mergepoint=getattr(e, 'mergepoint', None),
+                          branchpoints=getattr(e, 'branchpoints', set()))
             changesets.append(c)
             files = set()
             if len(changesets) % 100 == 0:
@@ -613,8 +645,17 @@
         if c.branch in branches:
             p = branches[c.branch]
         else:
-            for f in c.entries:
-                p = max(p, versions.get((f.rcs, f.parent), None))
+            # first changeset on a new branch
+            # the parent is a changeset with the branch in its
+            # branchpoints such that it is the latest possible
+            # commit without any intervening, unrelated commits.
+
+            for candidate in xrange(i):
+                if c.branch not in changesets[candidate].branchpoints:
+                    if p is not None:
+                        break
+                    continue
+                p = candidate
 
         c.parents = []
         if p is not None:
@@ -753,6 +794,9 @@
             ui.write('Branch: %s\n' % (cs.branch or 'HEAD'))
             ui.write('Tag%s: %s \n' % (['', 's'][len(cs.tags)>1],
                                   ','.join(cs.tags) or '(none)'))
+            branchpoints = getattr(cs, 'branchpoints', None)
+            if branchpoints:
+                ui.write('Branchpoints: %s \n' % ', '.join(branchpoints))
             if opts["parents"] and cs.parents:
                 if len(cs.parents)>1:
                     ui.write('Parents: %s\n' % (','.join([str(p.id) for p in cs.parents])))