more merge fixes

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

more merge fixes

Logic for getting a remote change should work going backwards and forwards

Mark all the changes in the merge that we don't get or merge so we
have the right list of files in the changeset

manifest hash: 88be742f510a2c58b276172ae538f9533f5e7491
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Version: GnuPG v1.4.0 (GNU/Linux)

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K2CqUESHr2+0J96q3N74Siw=
=zb2f
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mercurial/hg.py

@@ -1,1286 +1,1298 b''
 # hg.py - repository classes for mercurial
 #
 # Copyright 2005 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms
 # of the GNU General Public License, incorporated herein by reference.
 
 import sys, struct, os
 from revlog import *
 from demandload import *
 demandload(globals(), "re lock urllib urllib2 transaction time socket")
 demandload(globals(), "tempfile byterange difflib")
 
 def is_exec(f):
     return (os.stat(f).st_mode & 0100 != 0)
 
 def set_exec(f, mode):
     s = os.stat(f).st_mode
     if (s & 0100 != 0) == mode:
         return
     if mode:
         # Turn on +x for every +r bit when making a file executable
         # and obey umask.
         umask = os.umask(0)
         os.umask(umask)
         os.chmod(f, s | (s & 0444) >> 2 & ~umask)
     else:
         os.chmod(f, s & 0666)
 
 class filelog(revlog):
     def __init__(self, opener, path):
         revlog.__init__(self, opener,
                         os.path.join("data", path + ".i"),
                         os.path.join("data", path + ".d"))
 
     def read(self, node):
         return self.revision(node)
     def add(self, text, transaction, link, p1=None, p2=None):
         return self.addrevision(text, transaction, link, p1, p2)
 
     def annotate(self, node):
 
         def decorate(text, rev):
             return [(rev, l) for l in text.splitlines(1)]
 
         def strip(annotation):
             return [e[1] for e in annotation]
 
         def pair(parent, child):
             new = []
             sm = difflib.SequenceMatcher(None, strip(parent), strip(child))
             for o, m, n, s, t in sm.get_opcodes():
                 if o == 'equal':
                     new += parent[m:n]
                 else:
                     new += child[s:t]
             return new
 
         # find all ancestors
         needed = {node:1}
         visit = [node]
         while visit:
             n = visit.pop(0)
             for p in self.parents(n):
                 if p not in needed:
                     needed[p] = 1
                     visit.append(p)
                 else:
                     # count how many times we'll use this
                     needed[p] += 1
 
         # sort by revision which is a topological order
         visit = needed.keys()
         visit = [ (self.rev(n), n) for n in visit ]
         visit.sort()
         visit = [ p[1] for p in visit ]
         hist = {}
 
         for n in visit:
             curr = decorate(self.read(n), self.linkrev(n))
             for p in self.parents(n):
                 if p != nullid:
                     curr = pair(hist[p], curr)
                     # trim the history of unneeded revs
                     needed[p] -= 1
                     if not needed[p]:
                         del hist[p]
             hist[n] = curr
 
         return hist[n]
 
 class manifest(revlog):
     def __init__(self, opener):
         self.mapcache = None
         self.listcache = None
         self.addlist = None
         revlog.__init__(self, opener, "00manifest.i", "00manifest.d")
 
     def read(self, node):
         if self.mapcache and self.mapcache[0] == node:
             return self.mapcache[1].copy()
         text = self.revision(node)
         map = {}
         flag = {}
         self.listcache = (text, text.splitlines(1))
         for l in self.listcache[1]:
             (f, n) = l.split('\0')
             map[f] = bin(n[:40])
             flag[f] = (n[40:-1] == "x")
         self.mapcache = (node, map, flag)
         return map
 
     def readflags(self, node):
         if self.mapcache or self.mapcache[0] != node:
             self.read(node)
         return self.mapcache[2]
 
     def diff(self, a, b):
         # this is sneaky, as we're not actually using a and b
         if self.listcache and self.addlist and self.listcache[0] == a:
             d = mdiff.diff(self.listcache[1], self.addlist, 1)
             if mdiff.patch(a, d) != b:
                 sys.stderr.write("*** sortdiff failed, falling back ***\n")
                 return mdiff.textdiff(a, b)
             return d
         else:
             return mdiff.textdiff(a, b)
 
     def add(self, map, flags, transaction, link, p1=None, p2=None):
         files = map.keys()
         files.sort()
 
         self.addlist = ["%s\000%s%s\n" %
                         (f, hex(map[f]), flags[f] and "x" or '')
                         for f in files]
         text = "".join(self.addlist)
 
         n = self.addrevision(text, transaction, link, p1, p2)
         self.mapcache = (n, map, flags)
         self.listcache = (text, self.addlist)
         self.addlist = None
 
         return n
 
 class changelog(revlog):
     def __init__(self, opener):
         revlog.__init__(self, opener, "00changelog.i", "00changelog.d")
 
     def extract(self, text):
         if not text:
             return (nullid, "", "0", [], "")
         last = text.index("\n\n")
         desc = text[last + 2:]
         l = text[:last].splitlines()
         manifest = bin(l[0])
         user = l[1]
         date = l[2]
         files = l[3:]
         return (manifest, user, date, files, desc)
 
     def read(self, node):
         return self.extract(self.revision(node))
 
     def add(self, manifest, list, desc, transaction, p1=None, p2=None,
                   user=None, date=None):
         user = (user or
                 os.environ.get("HGUSER") or
                 os.environ.get("EMAIL") or
                 os.environ.get("LOGNAME", "unknown") + '@' + socket.getfqdn())
         date = date or "%d %d" % (time.time(), time.timezone)
         list.sort()
         l = [hex(manifest), user, date] + list + ["", desc]
         text = "\n".join(l)
         return self.addrevision(text, transaction, self.count(), p1, p2)
 
 class dirstate:
     def __init__(self, opener, ui, root):
         self.opener = opener
         self.root = root
         self.dirty = 0
         self.ui = ui
         self.map = None
         self.pl = None
 
     def __del__(self):
         if self.dirty:
             self.write()
 
     def __getitem__(self, key):
         try:
             return self.map[key]
         except TypeError:
             self.read()
             return self[key]
 
     def __contains__(self, key):
         if not self.map: self.read()
         return key in self.map
 
     def parents(self):
         if not self.pl:
             self.read()
         return self.pl
 
     def setparents(self, p1, p2 = nullid):
         self.dirty = 1
         self.pl = p1, p2
 
     def state(self, key):
         try:
             return self[key][0]
         except KeyError:
             return "?"
 
     def read(self):
         if self.map is not None: return self.map
 
         self.map = {}
         self.pl = [nullid, nullid]
         try:
             st = self.opener("dirstate").read()
         except: return
 
         self.pl = [st[:20], st[20: 40]]
 
         pos = 40
         while pos < len(st):
             e = struct.unpack(">cllll", st[pos:pos+17])
             l = e[4]
             pos += 17
             f = st[pos:pos + l]
             self.map[f] = e[:4]
             pos += l
         
     def update(self, files, state):
         ''' current states:
         n  normal
         m  needs merging
         r  marked for removal
         a  marked for addition'''
 
         if not files: return
         self.read()
         self.dirty = 1
         for f in files:
             if state == "r":
                 self.map[f] = ('r', 0, 0, 0)
             else:
                 s = os.stat(os.path.join(self.root, f))
                 self.map[f] = (state, s.st_mode, s.st_size, s.st_mtime)
 
     def forget(self, files):
         if not files: return
         self.read()
         self.dirty = 1
         for f in files:
             try:
                 del self.map[f]
             except KeyError:
                 self.ui.warn("not in dirstate: %s!\n" % f)
                 pass
 
     def clear(self):
         self.map = {}
         self.dirty = 1
 
     def write(self):
         st = self.opener("dirstate", "w")
         st.write("".join(self.pl))
         for f, e in self.map.items():
             e = struct.pack(">cllll", e[0], e[1], e[2], e[3], len(f))
             st.write(e + f)
         self.dirty = 0
 
     def copy(self):
         self.read()
         return self.map.copy()
 
 # used to avoid circular references so destructors work
 def opener(base):
     p = base
     def o(path, mode="r"):
         if p[:7] == "http://":
             f = os.path.join(p, urllib.quote(path))
             return httprangereader(f)
 
         f = os.path.join(p, path)
 
         mode += "b" # for that other OS
 
         if mode[0] != "r":
             try:
                 s = os.stat(f)
             except OSError:
                 d = os.path.dirname(f)
                 if not os.path.isdir(d):
                     os.makedirs(d)
             else:
                 if s.st_nlink > 1:
                     file(f + ".tmp", "w").write(file(f).read())
                     os.rename(f+".tmp", f)
 
         return file(f, mode)
 
     return o
 
 class localrepository:
     def __init__(self, ui, path=None, create=0):
         self.remote = 0
         if path and path[:7] == "http://":
             self.remote = 1
             self.path = path
         else:
             if not path:
                 p = os.getcwd()
                 while not os.path.isdir(os.path.join(p, ".hg")):
                     p = os.path.dirname(p)
                     if p == "/": raise "No repo found"
                 path = p
             self.path = os.path.join(path, ".hg")
 
         self.root = path
         self.ui = ui
 
         if create:
             os.mkdir(self.path)  
             os.mkdir(self.join("data"))
 
         self.opener = opener(self.path)
         self.wopener = opener(self.root)
         self.manifest = manifest(self.opener)
         self.changelog = changelog(self.opener)
         self.ignorelist = None
         self.tags = None
 
         if not self.remote:
             self.dirstate = dirstate(self.opener, ui, self.root)
 
     def ignore(self, f):
         if self.ignorelist is None:
             self.ignorelist = []
             try:
                 l = self.wfile(".hgignore")
                 for pat in l:
                     if pat != "\n":
                         self.ignorelist.append(re.compile(pat[:-1]))
             except IOError: pass
         for pat in self.ignorelist:
             if pat.search(f): return True
         return False
 
     def lookup(self, key):
         if self.tags is None:
             self.tags = {}
             try:
                 # read each head of the tags file, ending with the tip
                 # and add each tag found to the map, with "newer" ones
                 # taking precedence
                 fl = self.file(".hgtags")
                 h = fl.heads()
                 h.reverse()
                 for r in h:
                     for l in fl.revision(r).splitlines():
                         if l:
                             n, k = l.split(" ")
                             self.tags[k] = bin(n)
             except KeyError: pass
         try:
             return self.tags[key]
         except KeyError:
             return self.changelog.lookup(key)
 
     def join(self, f):
         return os.path.join(self.path, f)
 
     def wjoin(self, f):
         return os.path.join(self.root, f)
 
     def file(self, f):
         if f[0] == '/': f = f[1:]
         return filelog(self.opener, f)
 
     def wfile(self, f, mode='r'):
         return self.wopener(f, mode)
 
     def transaction(self):
         # save dirstate for undo
         try:
             ds = self.opener("dirstate").read()
         except IOError:
             ds = ""
         self.opener("undo.dirstate", "w").write(ds)
         
         return transaction.transaction(self.opener, self.join("journal"),
                                        self.join("undo"))
 
     def recover(self):
         lock = self.lock()
         if os.path.exists(self.join("recover")):
             self.ui.status("attempting to rollback interrupted transaction\n")
             return transaction.rollback(self.opener, self.join("recover"))
         else:
             self.ui.warn("no interrupted transaction available\n")
 
     def undo(self):
         lock = self.lock()
         if os.path.exists(self.join("undo")):
             self.ui.status("attempting to rollback last transaction\n")
             transaction.rollback(self.opener, self.join("undo"))
             self.dirstate = None
             os.rename(self.join("undo.dirstate"), self.join("dirstate"))
             self.dirstate = dirstate(self.opener, self.ui, self.root)
         else:
             self.ui.warn("no undo information available\n")
 
     def lock(self, wait = 1):
         try:
             return lock.lock(self.join("lock"), 0)
         except lock.LockHeld, inst:
             if wait:
                 self.ui.warn("waiting for lock held by %s\n" % inst.args[0])
                 return lock.lock(self.join("lock"), wait)
             raise inst
 
     def rawcommit(self, files, text, user, date, p1=None, p2=None):
         p1 = p1 or self.dirstate.parents()[0] or nullid
         p2 = p2 or self.dirstate.parents()[1] or nullid
         c1 = self.changelog.read(p1)
         c2 = self.changelog.read(p2)
         m1 = self.manifest.read(c1[0])
         mf1 = self.manifest.readflags(c1[0])
         m2 = self.manifest.read(c2[0])
 
         tr = self.transaction()
         mm = m1.copy()
         mfm = mf1.copy()
         linkrev = self.changelog.count()
         for f in files:
             try:
                 t = self.wfile(f).read()
                 tm = is_exec(self.wjoin(f))
                 r = self.file(f)
                 mfm[f] = tm
                 mm[f] = r.add(t, tr, linkrev,
                               m1.get(f, nullid), m2.get(f, nullid))
             except IOError:
                 del mm[f]
                 del mfm[f]
 
         mnode = self.manifest.add(mm, mfm, tr, linkrev, c1[0], c2[0])
         n = self.changelog.add(mnode, files, text, tr, p1, p2, user, date)
         tr.close()
         self.dirstate.setparents(p1, p2)
         self.dirstate.clear()
         self.dirstate.update(files, "n")
 
     def commit(self, files = None, text = ""):
         commit = []
         remove = []
         if files:
             for f in files:
                 s = self.dirstate.state(f)
                 if s in 'nmai':
                     commit.append(f)
                 elif s == 'r':
                     remove.append(f)
                 else:
                     self.ui.warn("%s not tracked!\n" % f)
         else:
             (c, a, d, u) = self.diffdir(self.root)
             commit = c + a
             remove = d
 
         if not commit and not remove:
             self.ui.status("nothing changed\n")
             return
 
         p1, p2 = self.dirstate.parents()
         c1 = self.changelog.read(p1)
         c2 = self.changelog.read(p2)
         m1 = self.manifest.read(c1[0])
         mf1 = self.manifest.readflags(c1[0])
         m2 = self.manifest.read(c2[0])
         lock = self.lock()
         tr = self.transaction()
 
         # check in files
         new = {}
         linkrev = self.changelog.count()
         commit.sort()
         for f in commit:
             self.ui.note(f + "\n")
             try:
                 fp = self.wjoin(f)
                 mf1[f] = is_exec(fp)
                 t = file(fp).read()
             except IOError:
                 self.warn("trouble committing %s!\n" % f)
                 raise
 
             r = self.file(f)
             fp1 = m1.get(f, nullid)
             fp2 = m2.get(f, nullid)
             new[f] = r.add(t, tr, linkrev, fp1, fp2)
 
         # update manifest
         m1.update(new)
         for f in remove: del m1[f]
         mn = self.manifest.add(m1, mf1, tr, linkrev, c1[0], c2[0])
 
         # add changeset
         new = new.keys()
         new.sort()
 
         if not text:
             edittext = "\n" + "HG: manifest hash %s\n" % hex(mn)
             edittext += "".join(["HG: changed %s\n" % f for f in new])
             edittext += "".join(["HG: removed %s\n" % f for f in remove])
             edittext = self.ui.edit(edittext)
             if not edittext.rstrip():
                 return 1
             text = edittext
 
         n = self.changelog.add(mn, new, text, tr, p1, p2)
         tr.close()
 
         self.dirstate.setparents(n)
         self.dirstate.update(new, "n")
         self.dirstate.forget(remove)
 
     def diffdir(self, path, changeset = None):
         changed = []
         added = []
         unknown = []
         mf = {}
 
         if changeset:
             change = self.changelog.read(changeset)
             mf = self.manifest.read(change[0])
             dc = dict.fromkeys(mf)
         else:
             changeset = self.dirstate.parents()[0]
             change = self.changelog.read(changeset)
             mf = self.manifest.read(change[0])
             dc = self.dirstate.copy()
 
         def fcmp(fn):
             t1 = self.wfile(fn).read()
             t2 = self.file(fn).revision(mf[fn])
             return cmp(t1, t2)
 
         for dir, subdirs, files in os.walk(self.root):
             d = dir[len(self.root)+1:]
             if ".hg" in subdirs: subdirs.remove(".hg")
             
             for f in files:
                 fn = os.path.join(d, f)
                 try: s = os.stat(os.path.join(self.root, fn))
                 except: continue
                 if fn in dc:
                     c = dc[fn]
                     del dc[fn]
                     if not c:
                         if fcmp(fn):
                             changed.append(fn)
                     elif c[0] == 'm':
                         changed.append(fn)
                     elif c[0] == 'a':
                         added.append(fn)
                     elif c[0] == 'r':
                         unknown.append(fn)
                     elif c[2] != s.st_size or (c[1] ^ s.st_mode) & 0100:
                         changed.append(fn)
                     elif c[1] != s.st_mode or c[3] != s.st_mtime:
                         if fcmp(fn):
                             changed.append(fn)
                 else:
                     if self.ignore(fn): continue
                     unknown.append(fn)
 
         deleted = dc.keys()
         deleted.sort()
 
         return (changed, added, deleted, unknown)
 
     def diffrevs(self, node1, node2):
         changed, added = [], []
 
         change = self.changelog.read(node1)
         mf1 = self.manifest.read(change[0])
         change = self.changelog.read(node2)
         mf2 = self.manifest.read(change[0])
 
         for fn in mf2:
             if mf1.has_key(fn):
                 if mf1[fn] != mf2[fn]:
                     changed.append(fn)
                 del mf1[fn]
             else:
                 added.append(fn)
                 
         deleted = mf1.keys()
         deleted.sort()
     
         return (changed, added, deleted)
 
     def add(self, list):
         for f in list:
             p = self.wjoin(f)
             if not os.path.isfile(p):
                 self.ui.warn("%s does not exist!\n" % f)
             elif self.dirstate.state(f) == 'n':
                 self.ui.warn("%s already tracked!\n" % f)
             else:
                 self.dirstate.update([f], "a")
 
     def forget(self, list):
         for f in list:
             if self.dirstate.state(f) not in 'ai':
                 self.ui.warn("%s not added!\n" % f)
             else:
                 self.dirstate.forget([f])
 
     def remove(self, list):
         for f in list:
             p = self.wjoin(f)
             if os.path.isfile(p):
                 self.ui.warn("%s still exists!\n" % f)
             elif f not in self.dirstate:
                 self.ui.warn("%s not tracked!\n" % f)
             else:
                 self.dirstate.update([f], "r")
 
     def heads(self):
         return self.changelog.heads()
 
     def branches(self, nodes):
         if not nodes: nodes = [self.changelog.tip()]
         b = []
         for n in nodes:
             t = n
             while n:
                 p = self.changelog.parents(n)
                 if p[1] != nullid or p[0] == nullid:
                     b.append((t, n, p[0], p[1]))
                     break
                 n = p[0]
         return b
 
     def between(self, pairs):
         r = []
 
         for top, bottom in pairs:
             n, l, i = top, [], 0
             f = 1
 
             while n != bottom:
                 p = self.changelog.parents(n)[0]
                 if i == f:
                     l.append(n) 
                     f = f * 2
                 n = p
                 i += 1
 
             r.append(l)
 
         return r
 
     def newer(self, nodes):
         m = {}
         nl = []
         pm = {}
         cl = self.changelog
         t = l = cl.count()
 
         # find the lowest numbered node
         for n in nodes:
             l = min(l, cl.rev(n))
             m[n] = 1
 
         for i in xrange(l, t):
             n = cl.node(i)
             if n in m: # explicitly listed
                 pm[n] = 1
                 nl.append(n)
                 continue
             for p in cl.parents(n):
                 if p in pm: # parent listed
                     pm[n] = 1
                     nl.append(n)
                     break
 
         return nl
 
     def getchangegroup(self, remote):
         m = self.changelog.nodemap
         search = []
         fetch = []
         seen = {}
         seenbranch = {}
 
         # if we have an empty repo, fetch everything
         if self.changelog.tip() == nullid:
             self.ui.status("requesting all changes\n")
             return remote.changegroup([nullid])
 
         # otherwise, assume we're closer to the tip than the root
         self.ui.status("searching for changes\n")
         heads = remote.heads()
         unknown = []
         for h in heads:
             if h not in m:
                 unknown.append(h)
 
         if not unknown:
             self.ui.status("nothing to do!\n")
             return None
             
         unknown = remote.branches(unknown)
         while unknown:
             n = unknown.pop(0)
             seen[n[0]] = 1
             
             self.ui.debug("examining %s:%s\n" % (short(n[0]), short(n[1])))
             if n == nullid: break
             if n in seenbranch:
                 self.ui.debug("branch already found\n")
                 continue
             if n[1] and n[1] in m: # do we know the base?
                 self.ui.debug("found incomplete branch %s:%s\n"
                               % (short(n[0]), short(n[1])))
                 search.append(n) # schedule branch range for scanning
                 seenbranch[n] = 1
             else:
                 if n[2] in m and n[3] in m:
                     if n[1] not in fetch:
                         self.ui.debug("found new changeset %s\n" %
                                       short(n[1]))
                         fetch.append(n[1]) # earliest unknown
                         continue
 
                 r = []
                 for a in n[2:4]:
                     if a not in seen: r.append(a)
                     
                 if r:
                     self.ui.debug("requesting %s\n" %
                                 " ".join(map(short, r)))
                     for b in remote.branches(r):
                         self.ui.debug("received %s:%s\n" %
                                       (short(b[0]), short(b[1])))
                         if b[0] not in m and b[0] not in seen:
                             unknown.append(b)
   
         while search:
             n = search.pop(0)
             l = remote.between([(n[0], n[1])])[0]
             p = n[0]
             f = 1
             for i in l + [n[1]]:
                 if i in m:
                     if f <= 2:
                         self.ui.debug("found new branch changeset %s\n" %
                                           short(p))
                         fetch.append(p)
                     else:
                         self.ui.debug("narrowed branch search to %s:%s\n"
                                       % (short(p), short(i)))
                         search.append((p, i))
                     break
                 p, f = i, f * 2
 
         for f in fetch:
             if f in m:
                 raise "already have", short(f[:4])
 
         self.ui.note("adding new changesets starting at " +
                      " ".join([short(f) for f in fetch]) + "\n")
 
         return remote.changegroup(fetch)
     
     def changegroup(self, basenodes):
         nodes = self.newer(basenodes)
 
         # construct the link map
         linkmap = {}
         for n in nodes:
             linkmap[self.changelog.rev(n)] = n
 
         # construct a list of all changed files
         changed = {}
         for n in nodes:
             c = self.changelog.read(n)
             for f in c[3]:
                 changed[f] = 1
         changed = changed.keys()
         changed.sort()
 
         # the changegroup is changesets + manifests + all file revs
         revs = [ self.changelog.rev(n) for n in nodes ]
 
         for y in self.changelog.group(linkmap): yield y
         for y in self.manifest.group(linkmap): yield y
         for f in changed:
             yield struct.pack(">l", len(f) + 4) + f
             g = self.file(f).group(linkmap)
             for y in g:
                 yield y
 
     def addchangegroup(self, generator):
 
         class genread:
             def __init__(self, generator):
                 self.g = generator
                 self.buf = ""
             def read(self, l):
                 while l > len(self.buf):
                     try:
                         self.buf += self.g.next()
                     except StopIteration:
                         break
                 d, self.buf = self.buf[:l], self.buf[l:]
                 return d
                 
         def getchunk():
             d = source.read(4)
             if not d: return ""
             l = struct.unpack(">l", d)[0]
             if l <= 4: return ""
             return source.read(l - 4)
 
         def getgroup():
             while 1:
                 c = getchunk()
                 if not c: break
                 yield c
 
         def csmap(x):
             self.ui.debug("add changeset %s\n" % short(x))
             return self.changelog.count()
 
         def revmap(x):
             return self.changelog.rev(x)
 
         if not generator: return
         changesets = files = revisions = 0
 
         source = genread(generator)
         lock = self.lock()
         tr = self.transaction()
 
         # pull off the changeset group
         self.ui.status("adding changesets\n")
         co = self.changelog.tip()
         cn = self.changelog.addgroup(getgroup(), csmap, tr, 1) # unique
         changesets = self.changelog.rev(cn) - self.changelog.rev(co)
 
         # pull off the manifest group
         self.ui.status("adding manifests\n")
         mm = self.manifest.tip()
         mo = self.manifest.addgroup(getgroup(), revmap, tr)
 
         # process the files
         self.ui.status("adding file revisions\n")
         while 1:
             f = getchunk()
             if not f: break
             self.ui.debug("adding %s revisions\n" % f)
             fl = self.file(f)
             o = fl.tip()
             n = fl.addgroup(getgroup(), revmap, tr)
             revisions += fl.rev(n) - fl.rev(o)
             files += 1
 
         self.ui.status(("modified %d files, added %d changesets" +
                         " and %d new revisions\n")
                        % (files, changesets, revisions))
 
         tr.close()
         return
 
     def update(self, node, allow=False, force=False):
         pl = self.dirstate.parents()
         if not force and pl[1] != nullid:
             self.ui.warn("aborting: outstanding uncommitted merges\n")
             return
 
         p1, p2 = pl[0], node
+        pa = self.changelog.ancestor(p1, p2)
         m1n = self.changelog.read(p1)[0]
         m2n = self.changelog.read(p2)[0]
         man = self.manifest.ancestor(m1n, m2n)
         m1 = self.manifest.read(m1n)
         mf1 = self.manifest.readflags(m1n)
         m2 = self.manifest.read(m2n)
         mf2 = self.manifest.readflags(m2n)
         ma = self.manifest.read(man)
         mfa = self.manifest.readflags(m2n)
 
         (c, a, d, u) = self.diffdir(self.root)
 
         # resolve the manifest to determine which files
         # we care about merging
         self.ui.note("resolving manifests\n")
         self.ui.debug(" ancestor %s local %s remote %s\n" %
                       (short(man), short(m1n), short(m2n)))
 
         merge = {}
         get = {}
         remove = []
+        mark = {}
 
         # construct a working dir manifest
         mw = m1.copy()
         mfw = mf1.copy()
         for f in a + c + u:
             mw[f] = ""
             mfw[f] = is_exec(self.wjoin(f))
         for f in d:
             if f in mw: del mw[f]
 
         for f, n in mw.iteritems():
             if f in m2:
                 s = 0
 
                 # are files different?
                 if n != m2[f]:
                     a = ma.get(f, nullid)
                     # are both different from the ancestor?
                     if n != a and m2[f] != a:
                         self.ui.debug(" %s versions differ, resolve\n" % f)
                         merge[f] = (m1.get(f, nullid), m2[f])
                         # merge executable bits
                         # "if we changed or they changed, change in merge"
                         a, b, c = mfa.get(f, 0), mfw[f], mf2[f]
                         mode = ((a^b) | (a^c)) ^ a
                         merge[f] = (m1.get(f, nullid), m2[f], mode)
                         s = 1
-                    # is this an unmodified file or are we clobbering?
-                    elif mw[f] == m1[f] or force:
+                    # are we clobbering?
+                    # is remote's version newer?
+                    # or are we going back in time?
+                    elif force or m2[f] != a or (p2 == pa and mw[f] == m1[f]):
                         self.ui.debug(" remote %s is newer, get\n" % f)
                         get[f] = m2[f]
                         s = 1
+                    else:
+                        mark[f] = 1
 
                 if not s and mfw[f] != mf2[f]:
                     if force:
                         self.ui.debug(" updating permissions for %s\n" % f)
                         set_exec(self.wjoin(f), mf2[f])
                     else:
                         a, b, c = mfa.get(f, 0), mfw[f], mf2[f]
                         mode = ((a^b) | (a^c)) ^ a
                         if mode != b:
                             self.ui.debug(" updating permissions for %s\n" % f)
                             set_exec(self.wjoin(f), mode)
-
+                            mark[f] = 1
                 del m2[f]
             elif f in ma:
                 if not force and n != ma[f]:
                     r = self.ui.prompt(
                         (" local changed %s which remote deleted\n" % f) +
                         "(k)eep or (d)elete?", "[kd]", "k")
                     if r == "d":
                         remove.append(f)
                 else:
                     self.ui.debug("other deleted %s\n" % f)
                     remove.append(f) # other deleted it
             else:
                 if n == m1.get(f, nullid): # same as parent
                     self.ui.debug("remote deleted %s\n" % f)
                     remove.append(f)
                 else:
                     self.ui.debug("working dir created %s, keeping\n" % f)
 
         for f, n in m2.iteritems():
             if f[0] == "/": continue
             if not force and f in ma and n != ma[f]:
                 r = self.ui.prompt(
                     ("remote changed %s which local deleted\n" % f) +
                     "(k)eep or (d)elete?", "[kd]", "k")
                 if r == "d": remove.append(f)
             else:
                 self.ui.debug("remote created %s\n" % f)
                 get[f] = n
 
         del mw, m1, m2, ma
 
         if force:
             for f in merge:
                 get[f] = merge[f][1]
             merge = {}
 
-        if not merge:
+        if pa == p1 or pa == p2:
             # we don't need to do any magic, just jump to the new rev
             mode = 'n'
             p1, p2 = p2, nullid
         else:
             if not allow:
-                self.ui.status("the following files conflict:\n")
-                for f in merge:
-                    self.ui.status(" %s\n" % f)
-                self.ui.warn("aborting update due to conflicting files!\n")
-                self.ui.status("(use update -m to allow a merge)\n")
+                self.ui.status("this update spans a branch" +
+                               " affecting the following files:\n")
+                fl = merge.keys() + get.keys()
+                fl.sort()
+                for f in fl:
+                    cf = ""
+                    if f in merge: cf = " (resolve)"
+                    self.ui.status(" %s%s\n" % (f, cf))
+                self.ui.warn("aborting update spanning branches!\n")
+                self.ui.status("(use update -m to perform a branch merge)\n")
                 return 1
             # we have to remember what files we needed to get/change
             # because any file that's different from either one of its
             # parents must be in the changeset
             mode = 'm'
+            self.dirstate.update(mark.keys(), "m")
 
         self.dirstate.setparents(p1, p2)
 
         # get the files we don't need to change
         files = get.keys()
         files.sort()
         for f in files:
             if f[0] == "/": continue
             self.ui.note("getting %s\n" % f)
             t = self.file(f).read(get[f])
             try:
                 self.wfile(f, "w").write(t)
             except IOError:
                 os.makedirs(os.path.dirname(self.wjoin(f)))
                 self.wfile(f, "w").write(t)
             set_exec(self.wjoin(f), mf2[f])
             self.dirstate.update([f], mode)
 
         # merge the tricky bits
         files = merge.keys()
         files.sort()
         for f in files:
             self.ui.status("merging %s\n" % f)
             m, o, flag = merge[f]
             self.merge3(f, m, o)
             set_exec(self.wjoin(f), flag)
             self.dirstate.update([f], 'm')
 
         for f in remove:
             self.ui.note("removing %s\n" % f)
             os.unlink(f)
         if mode == 'n':
             self.dirstate.forget(remove)
         else:
             self.dirstate.update(remove, 'r')
 
     def merge3(self, fn, my, other):
         """perform a 3-way merge in the working directory"""
 
         def temp(prefix, node):
             pre = "%s~%s." % (os.path.basename(fn), prefix)
             (fd, name) = tempfile.mkstemp("", pre)
             f = os.fdopen(fd, "w")
             f.write(fl.revision(node))
             f.close()
             return name
 
         fl = self.file(fn)
         base = fl.ancestor(my, other)
         a = self.wjoin(fn)
         b = temp("other", other)
         c = temp("base", base)
 
         self.ui.note("resolving %s\n" % fn)
         self.ui.debug("file %s: other %s ancestor %s\n" %
                               (fn, short(other), short(base)))
 
         cmd = os.environ.get("HGMERGE", "hgmerge")
         r = os.system("%s %s %s %s" % (cmd, a, b, c))
         if r:
             self.ui.warn("merging %s failed!\n" % fn)
 
         os.unlink(b)
         os.unlink(c)
 
     def verify(self):
         filelinkrevs = {}
         filenodes = {}
         changesets = revisions = files = 0
         errors = 0
 
         seen = {}
         self.ui.status("checking changesets\n")
         for i in range(self.changelog.count()):
             changesets += 1
             n = self.changelog.node(i)
             if n in seen:
                 self.ui.warn("duplicate changeset at revision %d\n" % i)
                 errors += 1
             seen[n] = 1
             
             for p in self.changelog.parents(n):
                 if p not in self.changelog.nodemap:
                     self.ui.warn("changeset %s has unknown parent %s\n" %
                                  (short(n), short(p)))
                     errors += 1
             try:
                 changes = self.changelog.read(n)
             except Exception, inst:
                 self.ui.warn("unpacking changeset %s: %s\n" % (short(n), inst))
                 errors += 1
 
             for f in changes[3]:
                 filelinkrevs.setdefault(f, []).append(i)
 
         seen = {}
         self.ui.status("checking manifests\n")
         for i in range(self.manifest.count()):
             n = self.manifest.node(i)
             if n in seen:
                 self.ui.warn("duplicate manifest at revision %d\n" % i)
                 errors += 1
             seen[n] = 1
             
             for p in self.manifest.parents(n):
                 if p not in self.manifest.nodemap:
                     self.ui.warn("manifest %s has unknown parent %s\n" %
                             (short(n), short(p)))
                     errors += 1
 
             try:
                 delta = mdiff.patchtext(self.manifest.delta(n))
             except KeyboardInterrupt:
                 print "aborted"
                 sys.exit(0)
             except Exception, inst:
                 self.ui.warn("unpacking manifest %s: %s\n"
                              % (short(n), inst))
                 errors += 1
 
             ff = [ l.split('\0') for l in delta.splitlines() ]
             for f, fn in ff:
                 filenodes.setdefault(f, {})[bin(fn[:40])] = 1
 
         self.ui.status("crosschecking files in changesets and manifests\n")
         for f in filenodes:
             if f not in filelinkrevs:
                 self.ui.warn("file %s in manifest but not in changesets\n" % f)
                 errors += 1
 
         for f in filelinkrevs:
             if f not in filenodes:
                 self.ui.warn("file %s in changeset but not in manifest\n" % f)
                 errors += 1
 
         self.ui.status("checking files\n")
         ff = filenodes.keys()
         ff.sort()
         for f in ff:
             if f == "/dev/null": continue
             files += 1
             fl = self.file(f)
             nodes = { nullid: 1 }
             seen = {}
             for i in range(fl.count()):
                 revisions += 1
                 n = fl.node(i)
 
                 if n in seen:
                     self.ui.warn("%s: duplicate revision %d\n" % (f, i))
                     errors += 1
 
                 if n not in filenodes[f]:
                     self.ui.warn("%s: %d:%s not in manifests\n"
                                  % (f, i, short(n)))
                     print len(filenodes[f].keys()), fl.count(), f
                     errors += 1
                 else:
                     del filenodes[f][n]
 
                 flr = fl.linkrev(n)
                 if flr not in filelinkrevs[f]:
                     self.ui.warn("%s:%s points to unexpected changeset %d\n"
                             % (f, short(n), fl.linkrev(n)))
                     errors += 1
                 else:
                     filelinkrevs[f].remove(flr)
 
                 # verify contents
                 try:
                     t = fl.read(n)
                 except Exception, inst:
                     self.ui.warn("unpacking file %s %s: %s\n"
                                  % (f, short(n), inst))
                     errors += 1
 
                 # verify parents
                 (p1, p2) = fl.parents(n)
                 if p1 not in nodes:
                     self.ui.warn("file %s:%s unknown parent 1 %s" %
                             (f, short(n), short(p1)))
                     errors += 1
                 if p2 not in nodes:
                     self.ui.warn("file %s:%s unknown parent 2 %s" %
                             (f, short(n), short(p1)))
                     errors += 1
                 nodes[n] = 1
 
             # cross-check
             for node in filenodes[f]:
                 self.ui.warn("node %s in manifests not in %s\n"
                              % (hex(n), f))
                 errors += 1
 
         self.ui.status("%d files, %d changesets, %d total revisions\n" %
                        (files, changesets, revisions))
 
         if errors:
             self.ui.warn("%d integrity errors encountered!\n" % errors)
             return 1
 
 class remoterepository:
     def __init__(self, ui, path):
         self.url = path
         self.ui = ui
 
     def do_cmd(self, cmd, **args):
         self.ui.debug("sending %s command\n" % cmd)
         q = {"cmd": cmd}
         q.update(args)
         qs = urllib.urlencode(q)
         cu = "%s?%s" % (self.url, qs)
         return urllib.urlopen(cu)
 
     def heads(self):
         d = self.do_cmd("heads").read()
         try:
             return map(bin, d[:-1].split(" "))
         except:
             self.ui.warn("unexpected response:\n" + d[:400] + "\n...\n")
             raise
 
     def branches(self, nodes):
         n = " ".join(map(hex, nodes))
         d = self.do_cmd("branches", nodes=n).read()
         try:
             br = [ tuple(map(bin, b.split(" "))) for b in d.splitlines() ]
             return br
         except:
             self.ui.warn("unexpected response:\n" + d[:400] + "\n...\n")
             raise
 
     def between(self, pairs):
         n = "\n".join(["-".join(map(hex, p)) for p in pairs])
         d = self.do_cmd("between", pairs=n).read()
         try:
             p = [ l and map(bin, l.split(" ")) or [] for l in d.splitlines() ]
             return p
         except:
             self.ui.warn("unexpected response:\n" + d[:400] + "\n...\n")
             raise
 
     def changegroup(self, nodes):
         n = " ".join(map(hex, nodes))
         zd = zlib.decompressobj()
         f = self.do_cmd("changegroup", roots=n)
         bytes = 0
         while 1:
             d = f.read(4096)
             bytes += len(d)
             if not d:
                 yield zd.flush()
                 break
             yield zd.decompress(d)
         self.ui.note("%d bytes of data transfered\n" % bytes)
 
 def repository(ui, path=None, create=0):
     if path and path[:7] == "http://":
         return remoterepository(ui, path)
     if path and path[:5] == "hg://":
         return remoterepository(ui, path.replace("hg://", "http://"))
     if path and path[:11] == "old-http://":
         return localrepository(ui, path.replace("old-http://", "http://"))
     else:
         return localrepository(ui, path, create)
 
 class httprangereader:
     def __init__(self, url):
         self.url = url
         self.pos = 0
     def seek(self, pos):
         self.pos = pos
     def read(self, bytes=None):
         opener = urllib2.build_opener(byterange.HTTPRangeHandler())
         urllib2.install_opener(opener)
         req = urllib2.Request(self.url)
         end = ''
         if bytes: end = self.pos + bytes
         req.add_header('Range', 'bytes=%d-%s' % (self.pos, end))
         f = urllib2.urlopen(req)
         return f.read()