# 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 or any later version.

'''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.

If there is more than one file being compared and the "child" revision

is the working directory, any modifications made in the external diff

program will be copied back to the working directory from the temporary

directory.

The extdiff extension also allows you 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 meld, runs meld (no need to name twice).  If

  # the meld executable is not available, the meld tool in [merge-tools]

  # will be used, if available

  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' fnameescape(argv(0)) fnameescape(argv(1))"

Tool arguments can include variables that are expanded at runtime::

  $parent1, $plabel1 - filename, descriptive label of first parent

  $child,   $clabel  - filename, descriptive label of child revision

  $parent2, $plabel2 - filename, descriptive label of second parent

  $root              - repository root

  $parent is an alias for $parent1.

The extdiff extension will look in your [diff-tools] and [merge-tools]

sections for diff tool arguments, when none are specified in [extdiff].

::

  [extdiff]

  kdiff3 =

  [diff-tools]

  kdiff3.diffargs=--L1 '$plabel1' --L2 '$clabel' $parent $child

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 __future__ import absolute_import

import os

import re

import shutil

import stat

from mercurial.i18n import _

from mercurial.node import (

    nullid,

    short,

)

from mercurial import (

    archival,

    cmdutil,

    error,

    filemerge,

    formatter,

    pycompat,

    registrar,

    scmutil,

    util,

)

from mercurial.utils import (

    procutil,

    stringutil,

)

cmdtable = {}

command = registrar.command(cmdtable)

configtable = {}

configitem = registrar.configitem(configtable)

configitem('extdiff', br'opts\..*',

    default='',

    generic=True,

)

configitem('diff-tools', br'.*\.diffargs$',

    default=None,

    generic=True,

)

# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for

# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should

# be specifying the version(s) of Mercurial they are tested with, or

# leave the attribute unspecified.

testedwith = 'ships-with-hg-core'

def snapshot(ui, repo, files, node, tmproot, listsubrepos):

    '''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)

    fnsandstat = []

    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)))

    if files:

        repo.ui.setconfig("ui", "archivemeta", False)

        archival.archive(repo, base, node, 'files',

                         match=scmutil.matchfiles(repo, files),

                         subrepos=listsubrepos)

        for fn in sorted(files):

            wfn = util.pconvert(fn)

            ui.note('  %s\n' % wfn)

            if node is None:

                dest = os.path.join(base, wfn)

                fnsandstat.append((dest, repo.wjoin(fn), os.lstat(dest)))

    return dirname, fnsandstat

def dodiff(ui, repo, cmdline, pats, opts):

    '''Do the actual 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')

    do3way = '$parent2' in cmdline

    if revs and change:

        msg = _('cannot specify --rev and --change at the same time')

        raise error.Abort(msg)

    elif change:

        ctx2 = scmutil.revsingle(repo, change, None)

        ctx1a, ctx1b = ctx2.p1(), ctx2.p2()

    else:

        ctx1a, ctx2 = scmutil.revpair(repo, revs)

        if not revs:

            ctx1b = repo[None].p2()

        else:

            ctx1b = repo[nullid]

    node1a = ctx1a.node()

    node1b = ctx1b.node()

    node2 = ctx2.node()

    # Disable 3-way merge if there is only one parent

    if do3way:

        if node1b == nullid:

            do3way = False

    subrepos=opts.get('subrepos')

    matcher = scmutil.match(repo[node2], pats, opts)

    if opts.get('patch'):

        if subrepos:

            raise error.Abort(_('--patch cannot be used with --subrepos'))

        if node2 is None:

            raise error.Abort(_('--patch requires two revisions'))

    else:

        mod_a, add_a, rem_a = map(set, repo.status(node1a, node2, matcher,

                                                   listsubrepos=subrepos)[:3])

        if do3way:

            mod_b, add_b, rem_b = map(set,

                                      repo.status(node1b, node2, matcher,

                                                  listsubrepos=subrepos)[: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 = pycompat.mkdtemp(prefix='extdiff.')

    try:

        if not opts.get('patch'):

            # 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,

                             subrepos)[0]

            rev1a = '@%d' % repo[node1a].rev()

            if do3way:

                dir1b_files = mod_b | rem_b | ((mod_a | add_a) - add_b)

                dir1b = snapshot(ui, repo, dir1b_files, node1b, tmproot,

                                 subrepos)[0]

                rev1b = '@%d' % repo[node1b].rev()

            else:

                dir1b = None

                rev1b = ''

            fnsandstat = []

            # If node2 in not the wc or there is >1 change, copy it

            dir2root = ''

            rev2 = ''

            if node2:

                dir2 = snapshot(ui, repo, modadd, node2, tmproot, subrepos)[0]

                rev2 = '@%d' % repo[node2].rev()

            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, fnsandstat = snapshot(ui, repo, modadd, None, tmproot,

                                            subrepos)

            else:

                # This lets the diff tool open the changed file directly

                dir2 = ''

                dir2root = repo.root

            label1a = rev1a

            label1b = rev1b

            label2 = rev2

            # 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(tmproot, dir1a, common_file)

                label1a = common_file + rev1a

                if not os.path.isfile(dir1a):

                    dir1a = os.devnull

                if do3way:

                    dir1b = os.path.join(tmproot, dir1b, common_file)

                    label1b = common_file + rev1b

                    if not os.path.isfile(dir1b):

                        dir1b = os.devnull

                dir2 = os.path.join(dir2root, dir2, common_file)

                label2 = common_file + rev2

        else:

            template = 'hg-%h.patch'

            with formatter.nullformatter(ui, 'extdiff', {}) as fm:

                cmdutil.export(repo, [repo[node1a].rev(), repo[node2].rev()],

                               fm,

                               fntemplate=repo.vfs.reljoin(tmproot, template),

                               match=matcher)

            label1a = cmdutil.makefilename(repo[node1a], template)

            label2 = cmdutil.makefilename(repo[node2], template)

            dir1a = repo.vfs.reljoin(tmproot, label1a)

            dir2 = repo.vfs.reljoin(tmproot, label2)

            dir1b = None

            label1b = None

            fnsandstat = []

        ui.system(cmdline, cwd=tmproot, blockedtag='extdiff')

        for copy_fn, working_fn, st in fnsandstat:

            cpstat = os.lstat(copy_fn)

            # Some tools copy the file and attributes, so mtime may not detect

            # all changes.  A size check will detect more cases, but not all.

            # The only certain way to detect every case is to diff all files,

            # which could be expensive.

            # copyfile() carries over the permission, so the mode check could

            # be in an 'elif' branch, but for the case where the file has

            # changed without affecting mtime or size.

            if (cpstat[stat.ST_MTIME] != st[stat.ST_MTIME]

                or cpstat.st_size != st.st_size

                or (cpstat.st_mode & 0o100) != (st.st_mode & 0o100)):

                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)

extdiffopts = [

    ('o', 'option', [],

     _('pass option to comparison program'), _('OPT')),

    ('r', 'rev', [], _('revision'), _('REV')),

    ('c', 'change', '', _('change made by revision'), _('REV')),

    ('', 'patch', None, _('compare patches for two revisions'))

    ] + cmdutil.walkopts + cmdutil.subrepoopts

@command('extdiff',

    [('p', 'program', '', _('comparison program to run'), _('CMD')),

     ] + extdiffopts,

    _('hg extdiff [OPT]... [FILE]...'),

    helpcategory=command.CATEGORY_FILE_CONTENTS,

    inferrepo=True)

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.'''

    opts = pycompat.byteskwargs(opts)

    program = opts.get('program')

    option = opts.get('option')

    if not program:

        program = 'diff'

        option = option or ['-Npru']

    cmdline = ' '.join(map(procutil.shellquote, [program] + option))

    return dodiff(ui, repo, cmdline, pats, opts)

class savedcmd(object):

    """use external program to diff repository (or selected files)

    Show differences between revisions for the specified files, using

    the following program::