merge: supply base node to merge tools in the environment

Merge tools will be able to exploit this to correctly merge backouts.
This won't work fully, though, until issue 1327 is solved, since the
node information is not necessarily correct.

mercurial/filemerge.py

@@ -1,231 +1,232
 # filemerge.py - file-level merge handling for Mercurial
 #
 # Copyright 2006, 2007, 2008 Matt Mackall <[e-mail]>
 #
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2, incorporated herein by reference.
 
 from node import short
 from i18n import _
 import util, simplemerge, match
 import os, tempfile, re, filecmp
 
 def _toolstr(ui, tool, part, default=""):
     return ui.config("merge-tools", tool + "." + part, default)
 
 def _toolbool(ui, tool, part, default=False):
     return ui.configbool("merge-tools", tool + "." + part, default)
 
 _internal = ['internal:' + s
              for s in 'fail local other merge prompt dump'.split()]
 
 def _findtool(ui, tool):
     if tool in _internal:
         return tool
     k = _toolstr(ui, tool, "regkey")
     if k:
         p = util.lookup_reg(k, _toolstr(ui, tool, "regname"))
         if p:
             p = util.find_exe(p + _toolstr(ui, tool, "regappend"))
             if p:
                 return p
     return util.find_exe(_toolstr(ui, tool, "executable", tool))
 
 def _picktool(repo, ui, path, binary, symlink):
     def check(tool, pat, symlink, binary):
         tmsg = tool
         if pat:
             tmsg += " specified for " + pat
         if not _findtool(ui, tool):
             if pat: # explicitly requested tool deserves a warning
                 ui.warn(_("couldn't find merge tool %s\n") % tmsg)
             else: # configured but non-existing tools are more silent
                 ui.note(_("couldn't find merge tool %s\n") % tmsg)
         elif symlink and not _toolbool(ui, tool, "symlink"):
             ui.warn(_("tool %s can't handle symlinks\n") % tmsg)
         elif binary and not _toolbool(ui, tool, "binary"):
             ui.warn(_("tool %s can't handle binary\n") % tmsg)
         elif not util.gui() and _toolbool(ui, tool, "gui"):
             ui.warn(_("tool %s requires a GUI\n") % tmsg)
         else:
             return True
         return False
 
     # HGMERGE takes precedence
     hgmerge = os.environ.get("HGMERGE")
     if hgmerge:
         return (hgmerge, hgmerge)
 
     # then patterns
     for pat, tool in ui.configitems("merge-patterns"):
         mf = match.match(repo.root, '', [pat])
         if mf(path) and check(tool, pat, symlink, False):
                 toolpath = _findtool(ui, tool)
                 return (tool, '"' + toolpath + '"')
 
     # then merge tools
     tools = {}
     for k,v in ui.configitems("merge-tools"):
         t = k.split('.')[0]
         if t not in tools:
             tools[t] = int(_toolstr(ui, t, "priority", "0"))
     names = tools.keys()
     tools = sorted([(-p,t) for t,p in tools.items()])
     uimerge = ui.config("ui", "merge")
     if uimerge:
         if uimerge not in names:
             return (uimerge, uimerge)
         tools.insert(0, (None, uimerge)) # highest priority
     tools.append((None, "hgmerge")) # the old default, if found
     for p,t in tools:
         if check(t, None, symlink, binary):
             toolpath = _findtool(ui, t)
             return (t, '"' + toolpath + '"')
     # internal merge as last resort
     return (not (symlink or binary) and "internal:merge" or None, None)
 
 def _eoltype(data):
     "Guess the EOL type of a file"
     if '\0' in data: # binary
         return None
     if '\r\n' in data: # Windows
         return '\r\n'
     if '\r' in data: # Old Mac
         return '\r'
     if '\n' in data: # UNIX
         return '\n'
     return None # unknown
 
 def _matcheol(file, origfile):
     "Convert EOL markers in a file to match origfile"
     tostyle = _eoltype(open(origfile, "rb").read())
     if tostyle:
         data = open(file, "rb").read()
         style = _eoltype(data)
         if style:
             newdata = data.replace(style, tostyle)
             if newdata != data:
                 open(file, "wb").write(newdata)
 
 def filemerge(repo, mynode, orig, fcd, fco, fca):
     """perform a 3-way merge in the working directory
 
     mynode = parent node before merge
     orig = original local filename before merge
     fco = other file context
     fca = ancestor file context
     fcd = local file context for current/destination file
     """
 
     def temp(prefix, ctx):
         pre = "%s~%s." % (os.path.basename(ctx.path()), prefix)
         (fd, name) = tempfile.mkstemp(prefix=pre)
         data = repo.wwritedata(ctx.path(), ctx.data())
         f = os.fdopen(fd, "wb")
         f.write(data)
         f.close()
         return name
 
     def isbin(ctx):
         try:
             return util.binary(ctx.data())
         except IOError:
             return False
 
     if not fco.cmp(fcd.data()): # files identical?
         return None
 
     ui = repo.ui
     fd = fcd.path()
     binary = isbin(fcd) or isbin(fco) or isbin(fca)
     symlink = 'l' in fcd.flags() + fco.flags()
     tool, toolpath = _picktool(repo, ui, fd, binary, symlink)
     ui.debug("picked tool '%s' for %s (binary %s symlink %s)\n" %
                (tool, fd, binary, symlink))
 
     if not tool or tool == 'internal:prompt':
         tool = "internal:local"
         if ui.promptchoice(_(" no tool found to merge %s\n"
                              "keep (l)ocal or take (o)ther?") % fd,
                            (_("&Local"), _("&Other")), 0):
             tool = "internal:other"
     if tool == "internal:local":
         return 0
     if tool == "internal:other":
         repo.wwrite(fd, fco.data(), fco.flags())
         return 0
     if tool == "internal:fail":
         return 1
 
     # do the actual merge
     a = repo.wjoin(fd)
     b = temp("base", fca)
     c = temp("other", fco)
     out = ""
     back = a + ".orig"
     util.copyfile(a, back)
 
     if orig != fco.path():
         ui.status(_("merging %s and %s to %s\n") % (orig, fco.path(), fd))
     else:
         ui.status(_("merging %s\n") % fd)
 
     ui.debug("my %s other %s ancestor %s\n" % (fcd, fco, fca))
 
     # do we attempt to simplemerge first?
     if _toolbool(ui, tool, "premerge", not (binary or symlink)):
         r = simplemerge.simplemerge(ui, a, b, c, quiet=True)
         if not r:
             ui.debug(" premerge successful\n")
             os.unlink(back)
             os.unlink(b)
             os.unlink(c)
             return 0
         util.copyfile(back, a) # restore from backup and try again
 
     env = dict(HG_FILE=fd,
                HG_MY_NODE=short(mynode),
                HG_OTHER_NODE=str(fco.changectx()),
+               HG_BASE_NODE=str(fca.changectx()),
                HG_MY_ISLINK='l' in fcd.flags(),
                HG_OTHER_ISLINK='l' in fco.flags(),
                HG_BASE_ISLINK='l' in fca.flags())
 
     if tool == "internal:merge":
         r = simplemerge.simplemerge(ui, a, b, c, label=['local', 'other'])
     elif tool == 'internal:dump':
         a = repo.wjoin(fd)
         util.copyfile(a, a + ".local")
         repo.wwrite(fd + ".other", fco.data(), fco.flags())
         repo.wwrite(fd + ".base", fca.data(), fca.flags())
         return 1 # unresolved
     else:
         args = _toolstr(ui, tool, "args", '$local $base $other')
         if "$output" in args:
             out, a = a, back # read input from backup, write to original
         replace = dict(local=a, base=b, other=c, output=out)
         args = re.sub("\$(local|base|other|output)",
                       lambda x: '"%s"' % replace[x.group()[1:]], args)
         r = util.system(toolpath + ' ' + args, cwd=repo.root, environ=env)
 
     if not r and _toolbool(ui, tool, "checkconflicts"):
         if re.match("^(<<<<<<< .*|=======|>>>>>>> .*)$", fcd.data()):
             r = 1
 
     if not r and _toolbool(ui, tool, "checkchanged"):
         if filecmp.cmp(repo.wjoin(fd), back):
             if ui.promptchoice(_(" output file %s appears unchanged\n"
                                  "was merge successful (yn)?") % fd,
                                (_("&Yes"), _("&No")), 1):
                 r = 1
 
     if _toolbool(ui, tool, "fixeol"):
         _matcheol(repo.wjoin(fd), back)
 
     if r:
         ui.warn(_("merging %s failed!\n") % fd)
     else:
         os.unlink(back)
 
     os.unlink(b)
     os.unlink(c)
     return r