# 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 version 2 or any later version.
from node import nullid, nullrev, hex, bin
from i18n import _
import error, scmutil, util, filemerge, copies, subrepo
import errno, os, shutil
class mergestate(object):
'''track 3-way merge state of individual files'''
def __init__(self, repo):
self._repo = repo
self._dirty = False
self._read()
def reset(self, node=None):
self._state = {}
if node:
self._local = node
shutil.rmtree(self._repo.join("merge"), True)
self._dirty = False
def _read(self):
self._state = {}
try:
f = self._repo.opener("merge/state")
for i, l in enumerate(f):
if i == 0:
self._local = bin(l[:-1])
else:
bits = l[:-1].split("\0")
self._state[bits[0]] = bits[1:]
f.close()
except IOError, err:
if err.errno != errno.ENOENT:
raise
self._dirty = False
def commit(self):
if self._dirty:
f = self._repo.opener("merge/state", "w")
f.write(hex(self._local) + "\n")
for d, v in self._state.iteritems():
f.write("\0".join([d] + v) + "\n")
f.close()
self._dirty = False
def add(self, fcl, fco, fca, fd, flags):
hash = util.sha1(fcl.path()).hexdigest()
self._repo.opener.write("merge/" + hash, fcl.data())
self._state[fd] = ['u', hash, fcl.path(), fca.path(),
hex(fca.filenode()), fco.path(), flags]
self._dirty = True
def __contains__(self, dfile):
return dfile in self._state
def __getitem__(self, dfile):
return self._state[dfile][0]
def __iter__(self):
l = self._state.keys()
l.sort()
for f in l:
yield f
def mark(self, dfile, state):
self._state[dfile][0] = state
self._dirty = True
def resolve(self, dfile, wctx, octx):
if self[dfile] == 'r':
return 0
state, hash, lfile, afile, anode, ofile, flags = self._state[dfile]
f = self._repo.opener("merge/" + hash)
self._repo.wwrite(dfile, f.read(), flags)
f.close()
fcd = wctx[dfile]
fco = octx[ofile]
fca = self._repo.filectx(afile, fileid=anode)
r = filemerge.filemerge(self._repo, self._local, lfile, fcd, fco, fca)
if r is None:
# no real conflict
del self._state[dfile]
elif not r:
self.mark(dfile, 'r')
return r
def _checkunknownfile(repo, wctx, mctx, f):
return (not repo.dirstate._ignore(f)
and os.path.isfile(repo.wjoin(f))
and repo.dirstate.normalize(f) not in repo.dirstate
and mctx[f].cmp(wctx[f]))
def _checkunknown(repo, wctx, mctx):
"check for collisions between unknown files and files in mctx"
error = False
for f in mctx:
if f not in wctx and _checkunknownfile(repo, wctx, mctx, f):
error = True
wctx._repo.ui.warn(_("%s: untracked file differs\n") % f)
if error:
raise util.Abort(_("untracked files in working directory differ "
"from files in requested revision"))
def _checkcollision(mctx, wctx):
"check for case folding collisions in the destination context"
folded = {}
for fn in mctx:
fold = util.normcase(fn)
if fold in folded:
raise util.Abort(_("case-folding collision between %s and %s")
% (fn, folded[fold]))
folded[fold] = fn
if wctx:
# class to delay looking up copy mapping
class pathcopies(object):
@util.propertycache
def map(self):
# {dst@mctx: src@wctx} copy mapping
return copies.pathcopies(wctx, mctx)
pc = pathcopies()
for fn in wctx:
fold = util.normcase(fn)
mfn = folded.get(fold, None)
if mfn and mfn != fn and pc.map.get(mfn) != fn:
raise util.Abort(_("case-folding collision between %s and %s")
% (mfn, 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 = []
state = branchmerge and 'r' or 'f'
for f in wctx.deleted():
if f not in mctx:
action.append((f, state))
if not branchmerge:
for f in wctx.removed():
if f not in mctx:
action.append((f, "f"))
return action
def manifestmerge(repo, p1, p2, pa, overwrite, partial):
"""
Merge p1 and p2 with ancestor pa and generate merge action list
overwrite = whether we clobber working files
partial = function to filter file lists
"""
def fmerge(f, f2, fa):
"""merge flags"""
a, m, n = ma.flags(fa), m1.flags(f), m2.flags(f2)
if m == n: # flags agree
return m # unchanged
if m and n and not a: # flags set, don't agree, differ from parent
r = repo.ui.promptchoice(
_(" conflicting flags for %s\n"
"(n)one, e(x)ec or sym(l)ink?") % f,
(_("&None"), _("E&xec"), _("Sym&link")), 0)
if r == 1:
return "x" # Exec
if r == 2:
return "l" # Symlink
return ""
if m and m != a: # changed from a to m
return m
if n and n != a: # changed from a to n
if (n == 'l' or a == 'l') and m1.get(f) != ma.get(f):
# can't automatically merge symlink flag when there
# are file-level conflicts here, let filemerge take
# care of it
return m
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)
action, copy = [], {}
if overwrite:
pa = p1
elif pa == p2: # backwards
pa = p1.p1()
elif pa and repo.ui.configbool("merge", "followcopies", True):
copy, diverge, renamedelete = copies.mergecopies(repo, p1, p2, pa)
for of, fl in diverge.iteritems():
act("divergent renames", "dr", of, fl)
for of, fl in renamedelete.iteritems():
act("rename and delete", "rd", of, fl)
repo.ui.note(_("resolving manifests\n"))
repo.ui.debug(" overwrite: %s, partial: %s\n"
% (bool(overwrite), bool(partial)))
repo.ui.debug(" ancestor: %s, local: %s, remote: %s\n" % (pa, p1, p2))
m1, m2, ma = p1.manifest(), p2.manifest(), pa.manifest()
copied = set(copy.values())
if '.hgsubstate' in m1:
# check whether sub state is modified
for s in p1.substate:
if p1.sub(s).dirty():
m1['.hgsubstate'] += "+"
break
# Compare manifests
for f, n in m1.iteritems():
if partial and not partial(f):
continue
if f in m2:
rflags = fmerge(f, f, f)
a = ma.get(f, nullid)
if n == m2[f] or m2[f] == a: # same or local newer
# is file locally modified or flags need changing?
# dirstate flags may need to be made current
if m1.flags(f) != rflags or n[20:]:
act("update permissions", "e", f, rflags)
elif n == a: # remote newer
act("remote is newer", "g", f, rflags)
else: # both changed
act("versions differ", "m", f, f, f, rflags, False)
elif f in copied: # files we'll deal with on m2 side
pass
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))
else: # case 2 A,B/B/B or case 4,21 A/B/B
act("local copied/moved to " + f2, "m",
f, f2, f, fmerge(f, f2, f2), False)
elif f in ma: # clean, a different, no remote
if n != ma[f]:
if repo.ui.promptchoice(
_(" local changed %s which remote deleted\n"
"use (c)hanged version or (d)elete?") % f,
(_("&Changed"), _("&Delete")), 0):
act("prompt delete", "r", f)
else:
act("prompt keep", "a", f)
elif n[20:] == "a": # added, no remote
act("remote deleted", "f", f)
else:
act("other deleted", "r", f)
for f, n in m2.iteritems():
if partial and not partial(f):
continue
if f in m1 or f in copied: # files already visited
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 not in ma:
if (not overwrite
and _checkunknownfile(repo, p1, p2, f)):
rflags = fmerge(f, f, f)
act("remote differs from untracked local",
"m", f, f, f, rflags, False)
else:
act("remote created", "g", f, m2.flags(f))
elif n != ma[f]:
if repo.ui.promptchoice(
_("remote changed %s which local deleted\n"
"use (c)hanged version or leave (d)eleted?") % f,
(_("&Changed"), _("&Deleted")), 0) == 0:
act("prompt recreating", "g", f, m2.flags(f))
return action
def actionkey(a):
return a[1] == 'r' and -1 or 0, a
def applyupdates(repo, action, wctx, mctx, actx, overwrite):
"""apply the merge action list to the working directory
wctx is the working copy context
mctx is the context to be merged into the working copy
actx is the context of the common ancestor
Return a tuple of counts (updated, merged, removed, unresolved) that
describes how many files were affected by the update.
"""
updated, merged, removed, unresolved = 0, 0, 0, 0
ms = mergestate(repo)
ms.reset(wctx.p1().node())
moves = []
action.sort(key=actionkey)
# prescan for merges
for a in action:
f, m = a[:2]
if m == 'm': # merge
f2, fd, flags, move = a[2:]
if f == '.hgsubstate': # merged internally
continue
repo.ui.debug("preserving %s for resolve of %s\n" % (f, fd))
fcl = wctx[f]
fco = mctx[f2]
if mctx == actx: # backwards, use working dir parent as ancestor
if fcl.parents():
fca = fcl.p1()
else:
fca = repo.filectx(f, fileid=nullrev)
else:
fca = fcl.ancestor(fco, actx)
if not fca:
fca = repo.filectx(f, fileid=nullrev)
ms.add(fcl, fco, fca, fd, flags)
if f != fd and move:
moves.append(f)
audit = scmutil.pathauditor(repo.root)
# remove renamed files after safely stored
for f in moves:
if os.path.lexists(repo.wjoin(f)):
repo.ui.debug("removing %s\n" % f)
audit(f)
os.unlink(repo.wjoin(f))
numupdates = len(action)
for i, a in enumerate(action):
f, m = a[:2]
repo.ui.progress(_('updating'), i + 1, item=f, total=numupdates,
unit=_('files'))
if f and f[0] == "/":
continue
if m == "r": # remove
repo.ui.note(_("removing %s\n") % f)
audit(f)
if f == '.hgsubstate': # subrepo states need updating
subrepo.submerge(repo, wctx, mctx, wctx, overwrite)
try:
util.unlinkpath(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
if f == '.hgsubstate': # subrepo states need updating
subrepo.submerge(repo, wctx, mctx, wctx.ancestor(mctx),
overwrite)
continue
f2, fd, flags, move = a[2:]
repo.wopener.audit(fd)
r = ms.resolve(fd, wctx, mctx)
if r is not None and r > 0:
unresolved += 1
else:
if r is None:
updated += 1
else:
merged += 1
if (move and repo.dirstate.normalize(fd) != f
and os.path.lexists(repo.wjoin(f))):
repo.ui.debug("removing %s\n" % f)
audit(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)
t = None
updated += 1
if f == '.hgsubstate': # subrepo states need updating
subrepo.submerge(repo, wctx, mctx, wctx, overwrite)
elif m == "d": # directory rename
f2, fd, flags = a[2:]
if f:
repo.ui.note(_("moving %s to %s\n") % (f, fd))
audit(f)
t = wctx.filectx(f).data()
repo.wwrite(fd, t, flags)
util.unlinkpath(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(_("note: possible conflict - %s was renamed "
"multiple times to:\n") % f)
for nf in fl:
repo.ui.warn(" %s\n" % nf)
elif m == "rd": # rename and delete
fl = a[2]
repo.ui.warn(_("note: possible conflict - %s was deleted "
"and renamed to:\n") % f)
for nf in fl:
repo.ui.warn(" %s\n" % nf)
elif m == "e": # exec
flags = a[2]
repo.wopener.audit(f)
util.setflags(repo.wjoin(f), 'l' in flags, 'x' in flags)
ms.commit()
repo.ui.progress(_('updating'), None, total=numupdates, unit=_('files'))
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.drop(f)
elif m == "a": # re-add
if not branchmerge:
repo.dirstate.add(f)
elif m == "f": # forget
repo.dirstate.drop(f)
elif m == "e": # exec change
repo.dirstate.normallookup(f)
elif m == "g": # get
if branchmerge:
repo.dirstate.otherparent(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.
if f2 == fd: # file not locally copied/moved
repo.dirstate.normallookup(fd)
if move:
repo.dirstate.drop(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.drop(f)
def update(repo, node, branchmerge, force, partial, ancestor=None,
mergeancestor=False):
"""
Perform a merge between the working directory and the given node
node = the node to update to, or None if unspecified
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)
mergeancestor = if false, merging with an ancestor (fast-forward)
is only allowed between different named branches. This flag
is used by rebase extension as a temporary fix and should be
avoided in general.
The table below shows all the behaviors of the update command
given the -c and -C or no options, whether the working directory
is dirty, whether a revision is specified, and the relationship of
the parent rev to the target rev (linear, on the same named
branch, or on another named branch).
This logic is tested by test-update-branches.t.
-c -C dirty rev | linear same cross
n n n n | ok (1) x
n n n y | ok ok ok
n n y * | merge (2) (2)
n y * * | --- discard ---
y n y * | --- (3) ---
y n n * | --- ok ---
y y * * | --- (4) ---
x = can't happen
* = don't-care
1 = abort: crosses branches (use 'hg merge' or 'hg update -c')
2 = abort: crosses branches (use 'hg merge' to merge or
use 'hg update -C' to discard changes)
3 = abort: uncommitted local changes
4 = incompatible options (checked in commands.py)
Return the same tuple as applyupdates().
"""
onode = node
wlock = repo.wlock()
try:
wc = repo[None]
if node is None:
# tip of current branch
try:
node = repo.branchtip(wc.branch())
except error.RepoLookupError:
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
pl = wc.parents()
p1, p2 = pl[0], repo[node]
if ancestor:
pa = repo[ancestor]
else:
pa = p1.ancestor(p2)
fp1, fp2, xp1, xp2 = p1.node(), p2.node(), str(p1), str(p2)
### check phase
if not overwrite and len(pl) > 1:
raise util.Abort(_("outstanding uncommitted merges"))
if branchmerge:
if pa == p2:
raise util.Abort(_("merging with a working directory ancestor"
" has no effect"))
elif pa == p1:
if not mergeancestor and p1.branch() == p2.branch():
raise util.Abort(_("nothing to merge"),
hint=_("use 'hg update' "
"or check 'hg heads'"))
if not force and (wc.files() or wc.deleted()):
raise util.Abort(_("outstanding uncommitted changes"),
hint=_("use 'hg status' to list changes"))
for s in wc.substate:
if wc.sub(s).dirty():
raise util.Abort(_("outstanding uncommitted changes in "
"subrepository '%s'") % s)
elif not overwrite:
if pa == p1 or pa == p2: # linear
pass # all good
elif wc.dirty(missing=True):
raise util.Abort(_("crosses branches (merge branches or use"
" --clean to discard changes)"))
elif onode is None:
raise util.Abort(_("crosses branches (merge branches or update"
" --check to force update)"))
else:
# Allow jumping branches if clean and specific rev given
pa = p1
### calculate phase
action = []
folding = not util.checkcase(repo.path)
if folding:
# collision check is not needed for clean update
if (not branchmerge and
(force or not wc.dirty(missing=True, branch=False))):
_checkcollision(p2, None)
else:
_checkcollision(p2, wc)
if not force:
_checkunknown(repo, wc, 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, pa, overwrite)
if not partial:
repo.setparents(fp1, fp2)
recordupdates(repo, action, branchmerge)
if not branchmerge:
repo.dirstate.setbranch(p2.branch())
finally:
wlock.release()
if not partial:
repo.hook('update', parent1=xp1, parent2=xp2, error=stats[3])
return stats