# 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

If a program has a graphical interface, it might be interesting to tell

Mercurial about it. It will prevent the program from being mistakenly

used in a terminal-only environment (such as an SSH terminal session),

and will make :hg:`extdiff --per-file` open multiple file diffs at once

instead of one by one (if you still want to open file diffs one by one,

you can use the --confirm option).

Declaring that a tool has a graphical interface can be done with the

``gui`` flag next to where ``diffargs`` are specified:

::

  [diff-tools]

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

  kdiff3.gui = true

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

import subprocess

from mercurial.i18n import _

from mercurial.node import (

    nullid,

    short,

)

from mercurial import (

    archival,

    cmdutil,

    encoding,

    error,

    filemerge,

    formatter,

    pycompat,

    registrar,

    scmutil,

    util,

)

from mercurial.utils import (

    procutil,

    stringutil,

)

cmdtable = {}

command = registrar.command(cmdtable)

configtable = {}

configitem = registrar.configitem(configtable)

configitem(

    b'extdiff', br'opts\..*', default=b'', generic=True,

)

configitem(

    b'extdiff', br'gui\..*', generic=True,

)

configitem(

    b'diff-tools', br'.*\.diffargs$', default=None, generic=True,

)

configitem(

    b'diff-tools', br'.*\.gui$', 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 = b'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 == b"":

        dirname = b"root"

    if node is not None:

        dirname = b'%s.%s' % (dirname, short(node))

    base = os.path.join(tmproot, dirname)

    os.mkdir(base)

    fnsandstat = []

    if node is not None:

        ui.note(

            _(b'making snapshot of %d files from rev %s\n')

            % (len(files), short(node))

        )

    else:

        ui.note(

            _(b'making snapshot of %d files from working directory\n')

            % (len(files))

        )

    if files:

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

        archival.archive(

            repo,

            base,

            node,

            b'files',

            match=scmutil.matchfiles(repo, files),

            subrepos=listsubrepos,

        )

        for fn in sorted(files):

            wfn = util.pconvert(fn)

            ui.note(b'  %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 formatcmdline(

    cmdline,

    repo_root,

    do3way,

    parent1,

    plabel1,

    parent2,

    plabel2,

    child,

    clabel,

):

    # 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 = {

        b'parent': parent1,

        b'parent1': parent1,

        b'parent2': parent2,

        b'plabel1': plabel1,

        b'plabel2': plabel2,

        b'child': child,

        b'clabel': clabel,

        b'root': repo_root,

    }

    def quote(match):

        pre = match.group(2)

        key = match.group(3)

        if not do3way and key == b'parent2':

            return pre

        return pre + procutil.shellquote(replace[key])

    # Match parent2 first, so 'parent1?' will match both parent1 and parent

    regex = (

        br'''(['"]?)([^\s'"$]*)'''

        br'\$(parent2|parent1?|child|plabel1|plabel2|clabel|root)\1'

    )

    if not do3way and not re.search(regex, cmdline):

        cmdline += b' $parent1 $child'

    return re.sub(regex, quote, cmdline)

def _systembackground(cmd, environ=None, cwd=None):

    ''' like 'procutil.system', but returns the Popen object directly

        so we don't have to wait on it.

    '''

    cmd = procutil.quotecommand(cmd)

    env = procutil.shellenviron(environ)

    proc = subprocess.Popen(

        procutil.tonativestr(cmd),

        shell=True,

        close_fds=procutil.closefds,

        env=procutil.tonativeenv(env),

        cwd=pycompat.rapply(procutil.tonativestr, cwd),

    )

    return proc

def _runperfilediff(

    cmdline,

    repo_root,

    ui,

    guitool,

    do3way,

    confirm,

    commonfiles,

    tmproot,

    dir1a,

    dir1b,

    dir2root,

    dir2,

    rev1a,

    rev1b,

    rev2,

):

    # Note that we need to sort the list of files because it was

    # built in an "unstable" way and it's annoying to get files in a

    # random order, especially when "confirm" mode is enabled.

    waitprocs = []

    totalfiles = len(commonfiles)

    for idx, commonfile in enumerate(sorted(commonfiles)):

        path1a = os.path.join(tmproot, dir1a, commonfile)

        label1a = commonfile + rev1a

        if not os.path.isfile(path1a):

            path1a = os.devnull

        path1b = b''

        label1b = b''

        if do3way:

            path1b = os.path.join(tmproot, dir1b, commonfile)

            label1b = commonfile + rev1b

            if not os.path.isfile(path1b):

                path1b = os.devnull

        path2 = os.path.join(dir2root, dir2, commonfile)

        label2 = commonfile + rev2

        if confirm:

            # Prompt before showing this diff

            difffiles = _(b'diff %s (%d of %d)') % (

                commonfile,

                idx + 1,

                totalfiles,

            )

            responses = _(

                b'[Yns?]'

                b'$$ &Yes, show diff'

                b'$$ &No, skip this diff'

                b'$$ &Skip remaining diffs'

                b'$$ &? (display help)'

            )

            r = ui.promptchoice(b'%s %s' % (difffiles, responses))

            if r == 3:  # ?

                while r == 3:

                    for c, t in ui.extractchoices(responses)[1]:

                        ui.write(b'%s - %s\n' % (c, encoding.lower(t)))

                    r = ui.promptchoice(b'%s %s' % (difffiles, responses))

            if r == 0:  # yes

                pass

            elif r == 1:  # no

                continue

            elif r == 2:  # skip

                break

        curcmdline = formatcmdline(

            cmdline,

            repo_root,

            do3way=do3way,

            parent1=path1a,

            plabel1=label1a,

            parent2=path1b,

            plabel2=label1b,

            child=path2,

            clabel=label2,

        )

        if confirm or not guitool:

            # Run the comparison program and wait for it to exit

            # before we show the next file.

            # This is because either we need to wait for confirmation

            # from the user between each invocation, or because, as far

            # as we know, the tool doesn't have a GUI, in which case

            # we can't run multiple CLI programs at the same time.

            ui.debug(

                b'running %r in %s\n' % (pycompat.bytestr(curcmdline), tmproot)

            )

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

        else:

            # Run the comparison program but don't wait, as we're

            # going to rapid-fire each file diff and then wait on

            # the whole group.

            ui.debug(

                b'running %r in %s (backgrounded)\n'

                % (pycompat.bytestr(curcmdline), tmproot)

            )

            proc = _systembackground(curcmdline, cwd=tmproot)

            waitprocs.append(proc)

    if waitprocs:

        with ui.timeblockedsection(b'extdiff'):

            for proc in waitprocs:

                proc.wait()

def dodiff(ui, repo, cmdline, pats, opts, guitool=False):

    '''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(b'rev')

    change = opts.get(b'change')

    do3way = b'$parent2' in cmdline

    if revs and change:

        msg = _(b'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]

    perfile = opts.get(b'per_file')

    confirm = opts.get(b'confirm')

    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(b'subrepos')

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

    if opts.get(b'patch'):

        if subrepos:

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

        if perfile: