extdiff: add 3-way diff for merge changesets
This adds 3-way diff for merge changesets (using -c) and for diffing
the working directory context against two parents. To enable it, use
the new magic value '$parent2' in the argument line. In order to work,
your differ must support that the second parent argument is left out;
this will happen in 2-way mode. Default arguments are as before, without
enabling 3-way mode, ensuring backwards compatibility.
This also fixes a problem when diffing a merge changeset with a single
file change. Extdiff would sometimes do the wrong thing in that situation.
# extdiff.py - external diff program support for mercurial
#
# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2, incorporated herein by reference.
'''command to allow external programs to compare revisions
The extdiff Mercurial extension allows you to use external programs
to compare revisions, or revision with working directory. The external
diff programs are called with a configurable set of options and two
non-option arguments: paths to directories containing snapshots of
files to compare.
The extdiff extension also allows to configure new diff commands, so
you do not need to type "hg extdiff -p kdiff3" always. ::
[extdiff]
# add new command that runs GNU diff(1) in 'context diff' mode
cdiff = gdiff -Nprc5
## or the old way:
#cmd.cdiff = gdiff
#opts.cdiff = -Nprc5
# add new command called vdiff, runs kdiff3
vdiff = kdiff3
# add new command called meld, runs meld (no need to name twice)
meld =
# add new command called vimdiff, runs gvimdiff with DirDiff plugin
# (see http://www.vim.org/scripts/script.php?script_id=102) Non
# English user, be sure to put "let g:DirDiffDynamicDiffText = 1" in
# your .vimrc
vimdiff = gvim -f '+next' '+execute "DirDiff" argv(0) argv(1)'
You can use -I/-X and list of file or directory names like normal "hg
diff" command. The extdiff extension makes snapshots of only needed
files, so running the external diff program will actually be pretty
fast (at least faster than having to compare the entire tree).
'''
from mercurial.i18n import _
from mercurial.node import short, nullid
from mercurial import cmdutil, util, commands
import os, shlex, shutil, tempfile, re
def snapshot(ui, repo, files, node, tmproot):
'''snapshot files as of some revision
if not using snapshot, -I/-X does not work and recursive diff
in tools like kdiff3 and meld displays too many files.'''
dirname = os.path.basename(repo.root)
if dirname == "":
dirname = "root"
if node is not None:
dirname = '%s.%s' % (dirname, short(node))
base = os.path.join(tmproot, dirname)
os.mkdir(base)
if node is not None:
ui.note(_('making snapshot of %d files from rev %s\n') %
(len(files), short(node)))
else:
ui.note(_('making snapshot of %d files from working directory\n') %
(len(files)))
wopener = util.opener(base)
fns_and_mtime = []
ctx = repo[node]
for fn in files:
wfn = util.pconvert(fn)
if not wfn in ctx:
# File doesn't exist; could be a bogus modify
continue
ui.note(' %s\n' % wfn)
dest = os.path.join(base, wfn)
fctx = ctx[wfn]
data = repo.wwritedata(wfn, fctx.data())
if 'l' in fctx.flags():
wopener.symlink(data, wfn)
else:
wopener(wfn, 'w').write(data)
if 'x' in fctx.flags():
util.set_flags(dest, False, True)
if node is None:
fns_and_mtime.append((dest, repo.wjoin(fn), os.path.getmtime(dest)))
return dirname, fns_and_mtime
def dodiff(ui, repo, diffcmd, diffopts, pats, opts):
'''Do the actuall diff:
- copy to a temp structure if diffing 2 internal revisions
- copy to a temp structure if diffing working revision with
another one and more than 1 file is changed
- just invoke the diff for a single file in the working dir
'''
revs = opts.get('rev')
change = opts.get('change')
args = ' '.join(diffopts)
do3way = '$parent2' in args
if revs and change:
msg = _('cannot specify --rev and --change at the same time')
raise util.Abort(msg)
elif change:
node2 = repo.lookup(change)
node1a, node1b = repo.changelog.parents(node2)
else:
node1a, node2 = cmdutil.revpair(repo, revs)
if not revs:
node1b = repo.dirstate.parents()[1]
else:
node1b = nullid
# Disable 3-way merge if there is only one parent
if do3way:
if node1b == nullid:
do3way = False
matcher = cmdutil.match(repo, pats, opts)
mod_a, add_a, rem_a = map(set, repo.status(node1a, node2, matcher)[:3])
if do3way:
mod_b, add_b, rem_b = map(set, repo.status(node1b, node2, matcher)[:3])
else:
mod_b, add_b, rem_b = set(), set(), set()
modadd = mod_a | add_a | mod_b | add_b
common = modadd | rem_a | rem_b
if not common:
return 0
tmproot = tempfile.mkdtemp(prefix='extdiff.')
try:
# Always make a copy of node1a (and node1b, if applicable)
dir1a_files = mod_a | rem_a | ((mod_b | add_b) - add_a)
dir1a = snapshot(ui, repo, dir1a_files, node1a, tmproot)[0]
if do3way:
dir1b_files = mod_b | rem_b | ((mod_a | add_a) - add_b)
dir1b = snapshot(ui, repo, dir1b_files, node1b, tmproot)[0]
else:
dir1b = None
fns_and_mtime = []
# If node2 in not the wc or there is >1 change, copy it
dir2root = ''
if node2:
dir2 = snapshot(ui, repo, modadd, node2, tmproot)[0]
elif len(common) > 1:
#we only actually need to get the files to copy back to the working
#dir in this case (because the other cases are: diffing 2 revisions
#or single file -- in which case the file is already directly passed
#to the diff tool).
dir2, fns_and_mtime = snapshot(ui, repo, modadd, None, tmproot)
else:
# This lets the diff tool open the changed file directly
dir2 = ''
dir2root = repo.root
# If only one change, diff the files instead of the directories
# Handle bogus modifies correctly by checking if the files exist
if len(common) == 1:
common_file = util.localpath(common.pop())
dir1a = os.path.join(dir1a, common_file)
if not os.path.isfile(os.path.join(tmproot, dir1a)):
dir1a = os.devnull
if do3way:
dir1b = os.path.join(dir1b, common_file)
if not os.path.isfile(os.path.join(tmproot, dir1b)):
dir1b = os.devnull
dir2 = os.path.join(dir2root, dir2, common_file)
# Function to quote file/dir names in the argument string
# When not operating in 3-way mode, an empty string is returned for parent2
replace = dict(parent=dir1a, parent1=dir1a, parent2=dir1b, child=dir2)
def quote(match):
key = match.group()[1:]
if not do3way and key == 'parent2':
return ''
return util.shellquote(replace[key])
# Match parent2 first, so 'parent1?' will match both parent1 and parent
regex = '\$(parent2|parent1?|child)'
if not do3way and not re.search(regex, args):
args += ' $parent1 $child'
args = re.sub(regex, quote, args)
cmdline = util.shellquote(diffcmd) + ' ' + args
ui.debug('running %r in %s\n' % (cmdline, tmproot))
util.system(cmdline, cwd=tmproot)
for copy_fn, working_fn, mtime in fns_and_mtime:
if os.path.getmtime(copy_fn) != mtime:
ui.debug('file changed while diffing. '
'Overwriting: %s (src: %s)\n' % (working_fn, copy_fn))
util.copyfile(copy_fn, working_fn)
return 1
finally:
ui.note(_('cleaning up temp directory\n'))
shutil.rmtree(tmproot)
def extdiff(ui, repo, *pats, **opts):
'''use external program to diff repository (or selected files)
Show differences between revisions for the specified files, using
an external program. The default program used is diff, with
default options "-Npru".
To select a different program, use the -p/--program option. The
program will be passed the names of two directories to compare. To
pass additional options to the program, use -o/--option. These
will be passed before the names of the directories to compare.
When two revision arguments are given, then changes are shown
between those revisions. If only one revision is specified then
that revision is compared to the working directory, and, when no
revisions are specified, the working directory files are compared
to its parent.'''
program = opts['program'] or 'diff'
if opts['program']:
option = opts['option']
else:
option = opts['option'] or ['-Npru']
return dodiff(ui, repo, program, option, pats, opts)
cmdtable = {
"extdiff":
(extdiff,
[('p', 'program', '', _('comparison program to run')),
('o', 'option', [], _('pass option to comparison program')),
('r', 'rev', [], _('revision')),
('c', 'change', '', _('change made by revision')),
] + commands.walkopts,
_('hg extdiff [OPT]... [FILE]...')),
}
def uisetup(ui):
for cmd, path in ui.configitems('extdiff'):
if cmd.startswith('cmd.'):
cmd = cmd[4:]
if not path: path = cmd
diffopts = ui.config('extdiff', 'opts.' + cmd, '')
diffopts = diffopts and [diffopts] or []
elif cmd.startswith('opts.'):
continue
else:
# command = path opts
if path:
diffopts = shlex.split(path)
path = diffopts.pop(0)
else:
path, diffopts = cmd, []
def save(cmd, path, diffopts):
'''use closure to save diff command to use'''
def mydiff(ui, repo, *pats, **opts):
return dodiff(ui, repo, path, diffopts, pats, opts)
mydiff.__doc__ = _('''\
use %(path)s to diff repository (or selected files)
Show differences between revisions for the specified files, using the
%(path)s program.
When two revision arguments are given, then changes are shown between
those revisions. If only one revision is specified then that revision is
compared to the working directory, and, when no revisions are specified,
the working directory files are compared to its parent.\
''') % dict(path=util.uirepr(path))
return mydiff
cmdtable[cmd] = (save(cmd, path, diffopts),
cmdtable['extdiff'][1][1:],
_('hg %s [OPTION]... [FILE]...') % cmd)