# merge.py - directory-level update/merge handling for Mercurial
#
# Copyright 2006, 2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms
# of the GNU General Public License, incorporated herein by reference.
from node import nullid, nullrev
from i18n import _
import errno, util, os, heapq, filemerge
def _checkunknown(wctx, mctx):
"check for collisions between unknown files and files in mctx"
man = mctx.manifest()
for f in wctx.unknown():
if f in man:
if mctx.filectx(f).cmp(wctx.filectx(f).data()):
raise util.Abort(_("untracked file in working directory differs"
" from file in requested revision: '%s'")
% f)
def _checkcollision(mctx):
"check for case folding collisions in the destination context"
folded = {}
for fn in mctx.manifest():
fold = fn.lower()
if fold in folded:
raise util.Abort(_("case-folding collision between %s and %s")
% (fn, folded[fold]))
folded[fold] = fn
def _forgetremoved(wctx, mctx, branchmerge):
"""
Forget removed files
If we're jumping between revisions (as opposed to merging), and if
neither the working directory nor the target rev has the file,
then we need to remove it from the dirstate, to prevent the
dirstate from listing the file when it is no longer in the
manifest.
If we're merging, and the other revision has removed a file
that is not present in the working directory, we need to mark it
as removed.
"""
action = []
man = mctx.manifest()
state = branchmerge and 'r' or 'f'
for f in wctx.deleted():
if f not in man:
action.append((f, state))
if not branchmerge:
for f in wctx.removed():
if f not in man:
action.append((f, "f"))
return action
def _nonoverlap(d1, d2, d3):
"Return list of elements in d1 not in d2 or d3"
l = [d for d in d1 if d not in d3 and d not in d2]
l.sort()
return l
def _dirname(f):
s = f.rfind("/")
if s == -1:
return ""
return f[:s]
def _dirs(files):
d = {}
for f in files:
f = _dirname(f)
while f not in d:
d[f] = True
f = _dirname(f)
return d
def _findoldnames(fctx, limit):
"find files that path was copied from, back to linkrev limit"
old = {}
seen = {}
orig = fctx.path()
visit = [fctx]
while visit:
fc = visit.pop()
s = str(fc)
if s in seen:
continue
seen[s] = 1
if fc.path() != orig and fc.path() not in old:
old[fc.path()] = 1
if fc.rev() < limit:
continue
visit += fc.parents()
old = old.keys()
old.sort()
return old
def findcopies(repo, m1, m2, ma, limit):
"""
Find moves and copies between m1 and m2 back to limit linkrev
"""
wctx = repo.workingctx()
def makectx(f, n):
if len(n) == 20:
return repo.filectx(f, fileid=n)
return wctx.filectx(f)
ctx = util.cachefunc(makectx)
copy = {}
fullcopy = {}
diverge = {}
def checkcopies(f, m1, m2):
'''check possible copies of f from m1 to m2'''
c1 = ctx(f, m1[f])
for of in _findoldnames(c1, limit):
fullcopy[f] = of # remember for dir rename detection
if of in m2: # original file not in other manifest?
# if the original file is unchanged on the other branch,
# no merge needed
if m2[of] != ma.get(of):
c2 = ctx(of, m2[of])
ca = c1.ancestor(c2)
# related and named changed on only one side?
if ca and ca.path() == f or ca.path() == c2.path():
if c1 != ca or c2 != ca: # merge needed?
copy[f] = of
elif of in ma:
diverge.setdefault(of, []).append(f)
if not repo.ui.configbool("merge", "followcopies", True):
return {}, {}
# avoid silly behavior for update from empty dir
if not m1 or not m2 or not ma:
return {}, {}
repo.ui.debug(_(" searching for copies back to rev %d\n") % limit)
u1 = _nonoverlap(m1, m2, ma)
u2 = _nonoverlap(m2, m1, ma)
if u1:
repo.ui.debug(_(" unmatched files in local:\n %s\n")
% "\n ".join(u1))
if u2:
repo.ui.debug(_(" unmatched files in other:\n %s\n")
% "\n ".join(u2))
for f in u1:
checkcopies(f, m1, m2)
for f in u2:
checkcopies(f, m2, m1)
diverge2 = {}
for of, fl in diverge.items():
if len(fl) == 1:
del diverge[of] # not actually divergent
else:
diverge2.update(dict.fromkeys(fl)) # reverse map for below
if fullcopy:
repo.ui.debug(_(" all copies found (* = to merge, ! = divergent):\n"))
for f in fullcopy:
note = ""
if f in copy: note += "*"
if f in diverge2: note += "!"
repo.ui.debug(_(" %s -> %s %s\n") % (f, fullcopy[f], note))
del diverge2
if not fullcopy or not repo.ui.configbool("merge", "followdirs", True):
return copy, diverge
repo.ui.debug(_(" checking for directory renames\n"))
# generate a directory move map
d1, d2 = _dirs(m1), _dirs(m2)
invalid = {}
dirmove = {}
# examine each file copy for a potential directory move, which is
# when all the files in a directory are moved to a new directory
for dst, src in fullcopy.items():
dsrc, ddst = _dirname(src), _dirname(dst)
if dsrc in invalid:
# already seen to be uninteresting
continue
elif dsrc in d1 and ddst in d1:
# directory wasn't entirely moved locally
invalid[dsrc] = True
elif dsrc in d2 and ddst in d2:
# directory wasn't entirely moved remotely
invalid[dsrc] = True
elif dsrc in dirmove and dirmove[dsrc] != ddst:
# files from the same directory moved to two different places
invalid[dsrc] = True
else:
# looks good so far
dirmove[dsrc + "/"] = ddst + "/"
for i in invalid:
if i in dirmove:
del dirmove[i]
del d1, d2, invalid
if not dirmove:
return copy, diverge
for d in dirmove:
repo.ui.debug(_(" dir %s -> %s\n") % (d, dirmove[d]))
# check unaccounted nonoverlapping files against directory moves
for f in u1 + u2:
if f not in fullcopy:
for d in dirmove:
if f.startswith(d):
# new file added in a directory that was moved, move it
copy[f] = dirmove[d] + f[len(d):]
repo.ui.debug(_(" file %s -> %s\n") % (f, copy[f]))
break
return copy, diverge
def _symmetricdifference(repo, rev1, rev2):
"""symmetric difference of the sets of ancestors of rev1 and rev2
I.e. revisions that are ancestors of rev1 or rev2, but not both.
"""
# basic idea:
# - mark rev1 and rev2 with different colors
# - walk the graph in topological order with the help of a heap;
# for each revision r:
# - if r has only one color, we want to return it
# - add colors[r] to its parents
#
# We keep track of the number of revisions in the heap that
# we may be interested in. We stop walking the graph as soon
# as this number reaches 0.
WHITE = 1
BLACK = 2
ALLCOLORS = WHITE | BLACK
colors = {rev1: WHITE, rev2: BLACK}
cl = repo.changelog
visit = [-rev1, -rev2]
heapq.heapify(visit)
n_wanted = len(visit)
ret = []
while n_wanted:
r = -heapq.heappop(visit)
wanted = colors[r] != ALLCOLORS
n_wanted -= wanted
if wanted:
ret.append(r)
for p in cl.parentrevs(r):
if p == nullrev:
continue
if p not in colors:
# first time we see p; add it to visit
n_wanted += wanted
colors[p] = colors[r]
heapq.heappush(visit, -p)
elif colors[p] != ALLCOLORS and colors[p] != colors[r]:
# at first we thought we wanted p, but now
# we know we don't really want it
n_wanted -= 1
colors[p] |= colors[r]
del colors[r]
return ret
def manifestmerge(repo, p1, p2, pa, overwrite, partial):
"""
Merge p1 and p2 with ancestor ma and generate merge action list
overwrite = whether we clobber working files
partial = function to filter file lists
"""
repo.ui.note(_("resolving manifests\n"))
repo.ui.debug(_(" overwrite %s partial %s\n") % (overwrite, bool(partial)))
repo.ui.debug(_(" ancestor %s local %s remote %s\n") % (pa, p1, p2))
m1 = p1.manifest()
m2 = p2.manifest()
ma = pa.manifest()
backwards = (pa == p2)
action = []
copy = {}
diverge = {}
def fmerge(f, f2=None, fa=None):
"""merge flags"""
if not f2:
f2 = f
fa = f
a, m, n = ma.flags(fa), m1.flags(f), m2.flags(f2)
if m == n: # flags agree
return m # unchanged
if m and n: # flags are set but don't agree
if not a: # both differ from parent
r = repo.ui.prompt(
_(" conflicting flags for %s\n"
"(n)one, e(x)ec or sym(l)ink?") % f, "[nxl]", "n")
return r != "n" and r or ''
if m == a:
return n # changed from m to n
return m # changed from n to m
if m and m != a: # changed from a to m
return m
if n and n != a: # changed from a to n
return n
return '' # flag was cleared
def act(msg, m, f, *args):
repo.ui.debug(" %s: %s -> %s\n" % (f, msg, m))
action.append((f, m) + args)
if not (backwards or overwrite):
rev1 = p1.rev()
if rev1 is None:
# p1 is a workingctx
rev1 = p1.parents()[0].rev()
limit = min(_symmetricdifference(repo, rev1, p2.rev()))
copy, diverge = findcopies(repo, m1, m2, ma, limit)
for of, fl in diverge.items():
act("divergent renames", "dr", of, fl)
copied = dict.fromkeys(copy.values())
# Compare manifests
for f, n in m1.iteritems():
if partial and not partial(f):
continue
if f in m2:
if overwrite or backwards:
rflags = m2.flags(f)
else:
rflags = fmerge(f)
# are files different?
if n != m2[f]:
a = ma.get(f, nullid)
# are we clobbering?
if overwrite:
act("clobbering", "g", f, rflags)
# or are we going back in time and clean?
elif backwards and not n[20:]:
act("reverting", "g", f, rflags)
# are both different from the ancestor?
elif n != a and m2[f] != a:
act("versions differ", "m", f, f, f, rflags, False)
# is remote's version newer?
elif m2[f] != a:
act("remote is newer", "g", f, rflags)
# local is newer, not overwrite, check mode bits
elif m1.flags(f) != rflags:
act("update permissions", "e", f, rflags)
# contents same, check mode bits
elif m1.flags(f) != rflags:
act("update permissions", "e", f, rflags)
elif f in copied:
continue
elif f in copy:
f2 = copy[f]
if f2 not in m2: # directory rename
act("remote renamed directory to " + f2, "d",
f, None, f2, m1.flags(f))
elif f2 in m1: # case 2 A,B/B/B
act("local copied to " + f2, "m",
f, f2, f, fmerge(f, f2, f2), False)
else: # case 4,21 A/B/B
act("local moved to " + f2, "m",
f, f2, f, fmerge(f, f2, f2), False)
elif f in ma:
if n != ma[f] and not overwrite:
if repo.ui.prompt(
_(" local changed %s which remote deleted\n"
"use (c)hanged version or (d)elete?") % f,
_("[cd]"), _("c")) == _("d"):
act("prompt delete", "r", f)
else:
act("other deleted", "r", f)
else:
# file is created on branch or in working directory
if (overwrite and n[20:] != "u") or (backwards and not n[20:]):
act("remote deleted", "r", f)
for f, n in m2.iteritems():
if partial and not partial(f):
continue
if f in m1:
continue
if f in copied:
continue
if f in copy:
f2 = copy[f]
if f2 not in m1: # directory rename
act("local renamed directory to " + f2, "d",
None, f, f2, m2.flags(f))
elif f2 in m2: # rename case 1, A/A,B/A
act("remote copied to " + f, "m",
f2, f, f, fmerge(f2, f, f2), False)
else: # case 3,20 A/B/A
act("remote moved to " + f, "m",
f2, f, f, fmerge(f2, f, f2), True)
elif f in ma:
if overwrite or backwards:
act("recreating", "g", f, m2.flags(f))
elif n != ma[f]:
if repo.ui.prompt(
_("remote changed %s which local deleted\n"
"use (c)hanged version or leave (d)eleted?") % f,
_("[cd]"), _("c")) == _("c"):
act("prompt recreating", "g", f, m2.flags(f))
else:
act("remote created", "g", f, m2.flags(f))
return action
def applyupdates(repo, action, wctx, mctx):
"apply the merge action list to the working directory"
updated, merged, removed, unresolved = 0, 0, 0, 0
action.sort()
# prescan for copy/renames
for a in action:
f, m = a[:2]
if m == 'm': # merge
f2, fd, flags, move = a[2:]
if f != fd:
repo.ui.debug(_("copying %s to %s\n") % (f, fd))
repo.wwrite(fd, repo.wread(f), flags)
audit_path = util.path_auditor(repo.root)
for a in action:
f, m = a[:2]
if f and f[0] == "/":
continue
if m == "r": # remove
repo.ui.note(_("removing %s\n") % f)
audit_path(f)
try:
util.unlink(repo.wjoin(f))
except OSError, inst:
if inst.errno != errno.ENOENT:
repo.ui.warn(_("update failed to remove %s: %s!\n") %
(f, inst.strerror))
removed += 1
elif m == "m": # merge
f2, fd, flags, move = a[2:]
r = filemerge.filemerge(repo, f, fd, f2, wctx, mctx)
if r > 0:
unresolved += 1
else:
if r is None:
updated += 1
else:
merged += 1
util.set_flags(repo.wjoin(fd), flags)
if f != fd and move and util.lexists(repo.wjoin(f)):
repo.ui.debug(_("removing %s\n") % f)
os.unlink(repo.wjoin(f))
elif m == "g": # get
flags = a[2]
repo.ui.note(_("getting %s\n") % f)
t = mctx.filectx(f).data()
repo.wwrite(f, t, flags)
updated += 1
elif m == "d": # directory rename
f2, fd, flags = a[2:]
if f:
repo.ui.note(_("moving %s to %s\n") % (f, fd))
t = wctx.filectx(f).data()
repo.wwrite(fd, t, flags)
util.unlink(repo.wjoin(f))
if f2:
repo.ui.note(_("getting %s to %s\n") % (f2, fd))
t = mctx.filectx(f2).data()
repo.wwrite(fd, t, flags)
updated += 1
elif m == "dr": # divergent renames
fl = a[2]
repo.ui.warn("warning: detected divergent renames of %s to:\n" % f)
for nf in fl:
repo.ui.warn(" %s\n" % nf)
elif m == "e": # exec
flags = a[2]
util.set_flags(repo.wjoin(f), flags)
return updated, merged, removed, unresolved
def recordupdates(repo, action, branchmerge):
"record merge actions to the dirstate"
for a in action:
f, m = a[:2]
if m == "r": # remove
if branchmerge:
repo.dirstate.remove(f)
else:
repo.dirstate.forget(f)
elif m == "f": # forget
repo.dirstate.forget(f)
elif m in "ge": # get or exec change
if branchmerge:
repo.dirstate.normaldirty(f)
else:
repo.dirstate.normal(f)
elif m == "m": # merge
f2, fd, flag, move = a[2:]
if branchmerge:
# We've done a branch merge, mark this file as merged
# so that we properly record the merger later
repo.dirstate.merge(fd)
if f != f2: # copy/rename
if move:
repo.dirstate.remove(f)
if f != fd:
repo.dirstate.copy(f, fd)
else:
repo.dirstate.copy(f2, fd)
else:
# We've update-merged a locally modified file, so
# we set the dirstate to emulate a normal checkout
# of that file some time in the past. Thus our
# merge will appear as a normal local file
# modification.
repo.dirstate.normallookup(fd)
if move:
repo.dirstate.forget(f)
elif m == "d": # directory rename
f2, fd, flag = a[2:]
if not f2 and f not in repo.dirstate:
# untracked file moved
continue
if branchmerge:
repo.dirstate.add(fd)
if f:
repo.dirstate.remove(f)
repo.dirstate.copy(f, fd)
if f2:
repo.dirstate.copy(f2, fd)
else:
repo.dirstate.normal(fd)
if f:
repo.dirstate.forget(f)
def update(repo, node, branchmerge, force, partial):
"""
Perform a merge between the working directory and the given node
branchmerge = whether to merge between branches
force = whether to force branch merging or file overwriting
partial = a function to filter file lists (dirstate not updated)
"""
wlock = repo.wlock()
try:
wc = repo.workingctx()
if node is None:
# tip of current branch
try:
node = repo.branchtags()[wc.branch()]
except KeyError:
if wc.branch() == "default": # no default branch!
node = repo.lookup("tip") # update to tip
else:
raise util.Abort(_("branch %s not found") % wc.branch())
overwrite = force and not branchmerge
forcemerge = force and branchmerge
pl = wc.parents()
p1, p2 = pl[0], repo.changectx(node)
pa = p1.ancestor(p2)
fp1, fp2, xp1, xp2 = p1.node(), p2.node(), str(p1), str(p2)
fastforward = False
### check phase
if not overwrite and len(pl) > 1:
raise util.Abort(_("outstanding uncommitted merges"))
if pa == p1 or pa == p2: # is there a linear path from p1 to p2?
if branchmerge:
if p1.branch() != p2.branch() and pa != p2:
fastforward = True
else:
raise util.Abort(_("there is nothing to merge, just use "
"'hg update' or look at 'hg heads'"))
elif not (overwrite or branchmerge):
raise util.Abort(_("update spans branches, use 'hg merge' "
"or 'hg update -C' to lose changes"))
if branchmerge and not forcemerge:
if wc.files() or wc.deleted():
raise util.Abort(_("outstanding uncommitted changes"))
### calculate phase
action = []
if not force:
_checkunknown(wc, p2)
if not util.checkfolding(repo.path):
_checkcollision(p2)
action += _forgetremoved(wc, p2, branchmerge)
action += manifestmerge(repo, wc, p2, pa, overwrite, partial)
### apply phase
if not branchmerge: # just jump to the new rev
fp1, fp2, xp1, xp2 = fp2, nullid, xp2, ''
if not partial:
repo.hook('preupdate', throw=True, parent1=xp1, parent2=xp2)
stats = applyupdates(repo, action, wc, p2)
if not partial:
recordupdates(repo, action, branchmerge)
repo.dirstate.setparents(fp1, fp2)
if not branchmerge and not fastforward:
repo.dirstate.setbranch(p2.branch())
repo.hook('update', parent1=xp1, parent2=xp2, error=stats[3])
return stats
finally:
del wlock