allow update to switch to a different branch if the repo is clean

mercurial/merge.py

@@ -1,418 +1,422 b''
 # merge.py - directory-level update/merge handling for Mercurial
 #
 # Copyright 2006 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.
 
 from node import *
 from i18n import gettext as _
 from demandload import *
 demandload(globals(), "errno util os tempfile")
 
 def filemerge(repo, fw, fo, wctx, mctx):
     """perform a 3-way merge in the working directory
 
     fw = filename in the working directory
     fo = filename in other parent
     wctx, mctx = working and merge changecontexts
     """
 
     def temp(prefix, ctx):
         pre = "%s~%s." % (os.path.basename(ctx.path()), prefix)
         (fd, name) = tempfile.mkstemp(prefix=pre)
         f = os.fdopen(fd, "wb")
         repo.wwrite(ctx.path(), ctx.data(), f)
         f.close()
         return name
 
     fcm = wctx.filectx(fw)
     fco = mctx.filectx(fo)
 
     if not fco.cmp(fcm.data()): # files identical?
         return None
 
     fca = fcm.ancestor(fco)
     if not fca:
         fca = repo.filectx(fw, fileid=nullrev)
     a = repo.wjoin(fw)
     b = temp("base", fca)
     c = temp("other", fco)
 
     if fw != fo:
         repo.ui.status(_("merging %s and %s\n") % (fw, fo))
     else:
         repo.ui.status(_("merging %s\n") % fw)
 
     repo.ui.debug(_("my %s other %s ancestor %s\n") % (fcm, fco, fca))
 
     cmd = (os.environ.get("HGMERGE") or repo.ui.config("ui", "merge")
            or "hgmerge")
     r = util.system('%s "%s" "%s" "%s"' % (cmd, a, b, c), cwd=repo.root,
                     environ={'HG_FILE': fw,
                              'HG_MY_NODE': str(wctx.parents()[0]),
                              'HG_OTHER_NODE': str(mctx)})
     if r:
         repo.ui.warn(_("merging %s failed!\n") % fw)
 
     os.unlink(b)
     os.unlink(c)
     return r
 
 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(_("'%s' already exists in the working"
                                    " dir and differs from remote") % f)
 
 def forgetremoved(wctx, mctx):
     """
     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.
     """
 
     action = []
     man = mctx.manifest()
     for f in wctx.deleted() + 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 = []
     for d in d1:
         if d not in d3 and d not in d2:
             l.append(d)
 
     l.sort()
     return l
 
 def findold(fctx, limit):
     "find files that path was copied from, back to linkrev limit"
 
     old = {}
     orig = fctx.path()
     visit = [fctx]
     while visit:
         fc = visit.pop()
         if fc.rev() < limit:
             continue
         if fc.path() != orig and fc.path() not in old:
             old[fc.path()] = 1
         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
     """
 
     if not repo.ui.configbool("merge", "followcopies", True):
         return {}
 
     # avoid silly behavior for update from empty dir
     if not m1:
         return {}
 
     dcopies = repo.dirstate.copies()
     copy = {}
     match = {}
     u1 = nonoverlap(m1, m2, ma)
     u2 = nonoverlap(m2, m1, ma)
     ctx = util.cachefunc(lambda f,n: repo.filectx(f, fileid=n[:20]))
 
     def checkpair(c, f2, man):
         ''' check if an apparent pair actually matches '''
         c2 = ctx(f2, man[f2])
         ca = c.ancestor(c2)
         if ca and ca.path() == c.path() or ca.path() == c2.path():
             copy[c.path()] = f2
             copy[f2] = c.path()
 
     for f in u1:
         c = ctx(dcopies.get(f, f), m1[f])
         for of in findold(c, limit):
             if of in m2:
                 checkpair(c, of, m2)
             else:
                 match.setdefault(of, []).append(f)
 
     for f in u2:
         c = ctx(f, m2[f])
         for of in findold(c, limit):
             if of in m1:
                 checkpair(c, of, m1)
             elif of in match:
                 for mf in match[of]:
                     checkpair(c, mf, m1)
 
     return copy
 
 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 = {}
 
     def fmerge(f, f2=None, fa=None):
         """merge executable flags"""
         if not f2:
             f2 = f
             fa = f
         a, b, c = ma.execf(fa), m1.execf(f), m2.execf(f2)
         return ((a^b) | (a^c)) ^ a
 
     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):
         copy = findcopies(repo, m1, m2, ma, pa.rev())
 
     # Compare manifests
     for f, n in m1.iteritems():
         if partial and not partial(f):
             continue
         if f in m2:
             # are files different?
             if n != m2[f]:
                 a = ma.get(f, nullid)
                 # are both different from the ancestor?
                 if not overwrite and n != a and m2[f] != a:
                     act("versions differ", "m", f, f, f, fmerge(f), False)
                 # are we clobbering?
                 # is remote's version newer?
                 # or are we going back in time and clean?
                 elif overwrite or m2[f] != a or (backwards and not n[20:]):
                     act("remote is newer", "g", f, m2.execf(f))
                 # local is newer, not overwrite, check mode bits
                 elif fmerge(f) != m1.execf(f):
                     act("update permissions", "e", f, m2.execf(f))
             # contents same, check mode bits
             elif m1.execf(f) != m2.execf(f):
                 if overwrite or fmerge(f) != m1.execf(f):
                     act("update permissions", "e", f, m2.execf(f))
         elif f in copy:
             f2 = copy[f]
             if f in ma: # case 3,20 A/B/A
                 act("remote moved", "m", f, f2, f2, fmerge(f, f2, f), True)
             else:
                 if f2 in m1: # case 2 A,B/B/B
                     act("local copied", "m",
                         f, f2, f, fmerge(f, f2, f2), False)
                 else: # case 4,21 A/B/B
                     act("local moved", "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") % f) +
                     _("(k)eep or (d)elete?"), _("[kd]"), _("k")) == _("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 copy:
             f2 = copy[f]
             if f2 not in m2: # already seen
                 continue
             # rename case 1, A/A,B/A
             act("remote copied", "m", f2, f, f, fmerge(f2, f, f2), False)
         elif f in ma:
             if overwrite or backwards:
                 act("recreating", "g", f, m2.execf(f))
             elif n != ma[f]:
                 if repo.ui.prompt(
                     (_("remote changed %s which local deleted\n") % f) +
                     _("(k)eep or (d)elete?"), _("[kd]"), _("k")) == _("k"):
                     act("prompt recreating", "g", f, m2.execf(f))
         else:
             act("remote created", "g", f, m2.execf(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()
     for a in action:
         f, m = a[:2]
         if f[0] == "/":
             continue
         if m == "r": # remove
             repo.ui.note(_("removing %s\n") % f)
             util.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, flag, move = a[2:]
             r = filemerge(repo, f, f2, wctx, mctx)
             if r > 0:
                 unresolved += 1
             else:
                 if r is None:
                     updated += 1
                 else:
                     merged += 1
                 if f != fd:
                     repo.ui.debug(_("copying %s to %s\n") % (f, fd))
                     repo.wwrite(fd, repo.wread(f))
                     if move:
                         repo.ui.debug(_("removing %s\n") % f)
                         os.unlink(repo.wjoin(f))
             util.set_exec(repo.wjoin(fd), flag)
         elif m == "g": # get
             flag = a[2]
             repo.ui.note(_("getting %s\n") % f)
             t = mctx.filectx(f).data()
             repo.wwrite(f, t)
             util.set_exec(repo.wjoin(f), flag)
             updated += 1
         elif m == "e": # exec
             flag = a[2]
             util.set_exec(repo.wjoin(f), flag)
 
     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.update([f], 'r')
             else:
                 repo.dirstate.forget([f])
         elif m == "f": # forget
             repo.dirstate.forget([f])
         elif m == "g": # get
             if branchmerge:
                 repo.dirstate.update([f], 'n', st_mtime=-1)
             else:
                 repo.dirstate.update([f], 'n')
         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.update([fd], 'm')
                 if f != f2: # copy/rename
                     if move:
                         repo.dirstate.update([f], 'r')
                     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.update([fd], 'n', st_size=-1, st_mtime=-1)
                 if move:
                     repo.dirstate.forget([f])
 
 def update(repo, node, branchmerge, force, partial, wlock):
     """
     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 = working dir lock, if already held
     """
 
     if not wlock:
         wlock = repo.wlock()
 
     overwrite = force and not branchmerge
     forcemerge = force and branchmerge
     wc = repo.workingctx()
     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)
 
     ### 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:
             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"))
+    elif not branchmerge:
+        if not overwrite:
+            if wc.files():
+                raise util.Abort(_("outstanding uncommited changes, use "
+                                   "'hg update -C' to lose changes"))
+            else:
+                overwrite = True
     if branchmerge and not forcemerge:
         if wc.modified() or wc.added() or wc.removed():
             raise util.Abort(_("outstanding uncommitted changes"))
 
     ### calculate phase
     action = []
     if not force:
         checkunknown(wc, p2)
     if not branchmerge:
         action += forgetremoved(wc, p2)
     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)
         repo.hook('update', parent1=xp1, parent2=xp2, error=stats[3])
         if not branchmerge:
             repo.opener("branch", "w").write(p2.branch() + "\n")
 
     return stats
 

tests/test-merge5

@@ -1,20 +1,24 b''
 #!/bin/sh
 
 mkdir t
 cd t
 hg init
 echo This is file a1 > a
 echo This is file b1 > b
 hg add a b
 hg commit -m "commit #0" -d "1000000 0"
 echo This is file b22 > b
 hg commit -m"comment #1" -d "1000000 0"
 hg update 0
 rm b
 hg commit -A -m"comment #2" -d "1000000 0"
+
+echo This is file a > a
 # in theory, we shouldn't need the "-y" below, but it prevents
 # this test from hanging when "hg update" erroneously prompts the
 # user for "keep or delete"
+hg update -y 1 # should fail (unclean repo)
+hg revert a
 hg update -y 1
 
 exit 0

tests/test-merge5.out

@@ -1,3 +1,4 b''
 1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 removing b
-abort: update spans branches, use 'hg merge' or 'hg update -C' to lose changes
+abort: outstanding uncommited changes, use 'hg update -C' to lose changes
+1 files updated, 0 files merged, 0 files removed, 0 files unresolved

tests/test-up-local-change.out

@@ -1,136 +1,136 b''
 adding a
 1 files updated, 0 files merged, 0 files removed, 0 files unresolved
 0 files updated, 0 files merged, 0 files removed, 0 files unresolved
 diff -r 33aaa84a386b a
 --- a/a
 +++ b/a
 @@ -1,1 +1,1 @@ a
 -a
 +abc
 adding b
 M a
 changeset:   0:33aaa84a386b
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     1
 
 resolving manifests
  overwrite False partial False
  ancestor 33aaa84a386b local 33aaa84a386b+ remote 802f095af299
  a: versions differ -> m
  b: remote created -> g
 merging a
 my a@33aaa84a386b+ other a@802f095af299 ancestor a@33aaa84a386b
 getting b
 1 files updated, 1 files merged, 0 files removed, 0 files unresolved
 changeset:   1:802f095af299
 tag:         tip
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     2
 
 resolving manifests
  overwrite False partial False
  ancestor 33aaa84a386b local 802f095af299+ remote 33aaa84a386b
  b: remote deleted -> r
 removing b
 0 files updated, 0 files merged, 1 files removed, 0 files unresolved
 changeset:   0:33aaa84a386b
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     1
 
 abort: there is nothing to merge - use "hg update" instead
 failed
 changeset:   0:33aaa84a386b
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     1
 
 resolving manifests
  overwrite False partial False
  ancestor 33aaa84a386b local 33aaa84a386b+ remote 802f095af299
  a: versions differ -> m
  b: remote created -> g
 merging a
 my a@33aaa84a386b+ other a@802f095af299 ancestor a@33aaa84a386b
 getting b
 1 files updated, 1 files merged, 0 files removed, 0 files unresolved
 changeset:   1:802f095af299
 tag:         tip
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     2
 
 changeset:   1:802f095af299
 tag:         tip
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 files:       a b
 description:
 2
 
 
 changeset:   0:33aaa84a386b
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 files:       a
 description:
 1
 
 
 diff -r 802f095af299 a
 --- a/a
 +++ b/a
 @@ -1,1 +1,1 @@ a2
 -a2
 +abc
 1 files updated, 0 files merged, 1 files removed, 0 files unresolved
 adding b
 M a
 changeset:   1:802f095af299
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     2
 
-abort: update spans branches, use 'hg merge' or 'hg update -C' to lose changes
+abort: outstanding uncommited changes, use 'hg update -C' to lose changes
 failed
 abort: outstanding uncommitted changes
 failed
 resolving manifests
  overwrite False partial False
  ancestor 33aaa84a386b local 802f095af299+ remote 030602aee63d
  a: versions differ -> m
  b: versions differ -> m
 merging a
 my a@802f095af299+ other a@030602aee63d ancestor a@33aaa84a386b
 merging b
 my b@802f095af299+ other b@030602aee63d ancestor b@000000000000
 0 files updated, 2 files merged, 0 files removed, 0 files unresolved
 (branch merge, don't forget to commit)
 changeset:   1:802f095af299
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     2
 
 changeset:   2:030602aee63d
 tag:         tip
 parent:      0:33aaa84a386b
 user:        test
 date:        Mon Jan 12 13:46:40 1970 +0000
 summary:     3
 
 diff -r 802f095af299 a
 --- a/a
 +++ b/a
 @@ -1,1 +1,1 @@ a2
 -a2
 +abc
 adding a
 pulling from ../a
 requesting all changes
 adding changesets
 adding manifests
 adding file changes
 added 1 changesets with 1 changes to 1 files
 1 files updated, 0 files merged, 0 files removed, 0 files unresolved