-#!/usr/bin/env perl
+#!/usr/bin/perl
# Copyright (c) 2009, 2010 David Aguilar
+# Copyright (c) 2012 Tim Henigan
#
# This is a wrapper around the GIT_EXTERNAL_DIFF-compatible
# git-difftool--helper script.
#
# This script exports GIT_EXTERNAL_DIFF and GIT_PAGER for use by git.
-# GIT_DIFFTOOL_NO_PROMPT, GIT_DIFFTOOL_PROMPT, and GIT_DIFF_TOOL
-# are exported for use by git-difftool--helper.
+# The GIT_DIFF* variables are exported for use by git-difftool--helper.
#
# Any arguments that are unknown to this script are forwarded to 'git diff'.
use 5.008;
use strict;
use warnings;
-use Cwd qw(abs_path);
use File::Basename qw(dirname);
-
-require Git;
-
-my $DIR = abs_path(dirname($0));
-
+use File::Copy;
+use File::Compare;
+use File::Find;
+use File::stat;
+use File::Path qw(mkpath rmtree);
+use File::Temp qw(tempdir);
+use Getopt::Long qw(:config pass_through);
+use Git;
sub usage
{
+ my $exitcode = shift;
print << 'USAGE';
-usage: git difftool [-t|--tool=<tool>] [-x|--extcmd=<cmd>]
- [-y|--no-prompt] [-g|--gui]
+usage: git difftool [-t|--tool=<tool>] [--tool-help]
+ [-x|--extcmd=<cmd>]
+ [-g|--gui] [--no-gui]
+ [--prompt] [-y|--no-prompt]
+ [-d|--dir-diff]
['git diff' options]
USAGE
- exit 1;
+ exit($exitcode);
}
-sub setup_environment
+sub find_worktree
{
- $ENV{PATH} = "$DIR:$ENV{PATH}";
- $ENV{GIT_PAGER} = '';
- $ENV{GIT_EXTERNAL_DIFF} = 'git-difftool--helper';
+ my ($repo) = @_;
+
+ # Git->repository->wc_path() does not honor changes to the working
+ # tree location made by $ENV{GIT_WORK_TREE} or the 'core.worktree'
+ # config variable.
+ my $worktree;
+ my $env_worktree = $ENV{GIT_WORK_TREE};
+ my $core_worktree = Git::config('core.worktree');
+
+ if (defined($env_worktree) and (length($env_worktree) > 0)) {
+ $worktree = $env_worktree;
+ } elsif (defined($core_worktree) and (length($core_worktree) > 0)) {
+ $worktree = $core_worktree;
+ } else {
+ $worktree = $repo->wc_path();
+ }
+
+ return $worktree;
}
-sub exe
+sub filter_tool_scripts
{
- my $exe = shift;
- if ($^O eq 'MSWin32' || $^O eq 'msys') {
- return "$exe.exe";
+ my ($tools) = @_;
+ if (-d $_) {
+ if ($_ ne ".") {
+ # Ignore files in subdirectories
+ $File::Find::prune = 1;
+ }
+ } else {
+ if ((-f $_) && ($_ ne "defaults")) {
+ push(@$tools, $_);
+ }
}
- return $exe;
}
-sub generate_command
+sub print_tool_help
{
- my @command = (exe('git'), 'diff');
- my $skip_next = 0;
- my $idx = -1;
- my $prompt = '';
- for my $arg (@ARGV) {
- $idx++;
- if ($skip_next) {
- $skip_next = 0;
- next;
+ my ($cmd, @found, @notfound, @tools);
+ my $gitpath = Git::exec_path();
+
+ find(sub { filter_tool_scripts(\@tools) }, "$gitpath/mergetools");
+
+ foreach my $tool (@tools) {
+ $cmd = "TOOL_MODE=diff";
+ $cmd .= ' && . "$(git --exec-path)/git-mergetool--lib"';
+ $cmd .= " && get_merge_tool_path $tool >/dev/null 2>&1";
+ $cmd .= " && can_diff >/dev/null 2>&1";
+ if (system('sh', '-c', $cmd) == 0) {
+ push(@found, $tool);
+ } else {
+ push(@notfound, $tool);
}
- if ($arg eq '-t' || $arg eq '--tool') {
- usage() if $#ARGV <= $idx;
- $ENV{GIT_DIFF_TOOL} = $ARGV[$idx + 1];
- $skip_next = 1;
- next;
+ }
+
+ print << 'EOF';
+'git difftool --tool=<tool>' may be set to one of the following:
+EOF
+ print "\t$_\n" for (sort(@found));
+
+ print << 'EOF';
+
+The following tools are valid, but not currently available:
+EOF
+ print "\t$_\n" for (sort(@notfound));
+
+ print << 'EOF';
+
+NOTE: Some of the tools listed above only work in a windowed
+environment. If run in a terminal-only session, they will fail.
+EOF
+ exit(0);
+}
+
+sub exit_cleanup
+{
+ my ($tmpdir, $status) = @_;
+ my $errno = $!;
+ rmtree($tmpdir);
+ if ($status and $errno) {
+ my ($package, $file, $line) = caller();
+ warn "$file line $line: $errno\n";
+ }
+ exit($status | ($status >> 8));
+}
+
+sub setup_dir_diff
+{
+ my ($repo, $workdir, $symlinks) = @_;
+
+ # Run the diff; exit immediately if no diff found
+ # 'Repository' and 'WorkingCopy' must be explicitly set to insure that
+ # if $GIT_DIR and $GIT_WORK_TREE are set in ENV, they are actually used
+ # by Git->repository->command*.
+ my $repo_path = $repo->repo_path();
+ my %repo_args = (Repository => $repo_path, WorkingCopy => $workdir);
+ my $diffrepo = Git->repository(%repo_args);
+
+ my @gitargs = ('diff', '--raw', '--no-abbrev', '-z', @ARGV);
+ my $diffrtn = $diffrepo->command_oneline(@gitargs);
+ exit(0) unless defined($diffrtn);
+
+ # Build index info for left and right sides of the diff
+ my $submodule_mode = '160000';
+ my $symlink_mode = '120000';
+ my $null_mode = '0' x 6;
+ my $null_sha1 = '0' x 40;
+ my $lindex = '';
+ my $rindex = '';
+ my %submodule;
+ my %symlink;
+ my @working_tree = ();
+ my @rawdiff = split('\0', $diffrtn);
+
+ my $i = 0;
+ while ($i < $#rawdiff) {
+ if ($rawdiff[$i] =~ /^::/) {
+ warn << 'EOF';
+Combined diff formats ('-c' and '--cc') are not supported in
+directory diff mode ('-d' and '--dir-diff').
+EOF
+ exit(1);
}
- if ($arg =~ /^--tool=/) {
- $ENV{GIT_DIFF_TOOL} = substr($arg, 7);
- next;
+
+ my ($lmode, $rmode, $lsha1, $rsha1, $status) =
+ split(' ', substr($rawdiff[$i], 1));
+ my $src_path = $rawdiff[$i + 1];
+ my $dst_path;
+
+ if ($status =~ /^[CR]/) {
+ $dst_path = $rawdiff[$i + 2];
+ $i += 3;
+ } else {
+ $dst_path = $src_path;
+ $i += 2;
}
- if ($arg eq '-x' || $arg eq '--extcmd') {
- usage() if $#ARGV <= $idx;
- $ENV{GIT_DIFFTOOL_EXTCMD} = $ARGV[$idx + 1];
- $skip_next = 1;
+
+ if ($lmode eq $submodule_mode or $rmode eq $submodule_mode) {
+ $submodule{$src_path}{left} = $lsha1;
+ if ($lsha1 ne $rsha1) {
+ $submodule{$dst_path}{right} = $rsha1;
+ } else {
+ $submodule{$dst_path}{right} = "$rsha1-dirty";
+ }
next;
}
- if ($arg =~ /^--extcmd=/) {
- $ENV{GIT_DIFFTOOL_EXTCMD} = substr($arg, 9);
- next;
+
+ if ($lmode eq $symlink_mode) {
+ $symlink{$src_path}{left} =
+ $diffrepo->command_oneline('show', "$lsha1");
}
- if ($arg eq '-g' || $arg eq '--gui') {
- eval {
- my $tool = Git::command_oneline('config',
- 'diff.guitool');
- if (length($tool)) {
- $ENV{GIT_DIFF_TOOL} = $tool;
- }
- };
- next;
+
+ if ($rmode eq $symlink_mode) {
+ $symlink{$dst_path}{right} =
+ $diffrepo->command_oneline('show', "$rsha1");
}
- if ($arg eq '-y' || $arg eq '--no-prompt') {
- $prompt = 'no';
- next;
+
+ if ($lmode ne $null_mode and $status !~ /^C/) {
+ $lindex .= "$lmode $lsha1\t$src_path\0";
}
- if ($arg eq '--prompt') {
- $prompt = 'yes';
- next;
+
+ if ($rmode ne $null_mode) {
+ if ($rsha1 ne $null_sha1) {
+ $rindex .= "$rmode $rsha1\t$dst_path\0";
+ } else {
+ push(@working_tree, $dst_path);
+ }
+ }
+ }
+
+ # Setup temp directories
+ my $tmpdir = tempdir('git-difftool.XXXXX', CLEANUP => 0, TMPDIR => 1);
+ my $ldir = "$tmpdir/left";
+ my $rdir = "$tmpdir/right";
+ mkpath($ldir) or exit_cleanup($tmpdir, 1);
+ mkpath($rdir) or exit_cleanup($tmpdir, 1);
+
+ # If $GIT_DIR is not set prior to calling 'git update-index' and
+ # 'git checkout-index', then those commands will fail if difftool
+ # is called from a directory other than the repo root.
+ my $must_unset_git_dir = 0;
+ if (not defined($ENV{GIT_DIR})) {
+ $must_unset_git_dir = 1;
+ $ENV{GIT_DIR} = $repo_path;
+ }
+
+ # Populate the left and right directories based on each index file
+ my ($inpipe, $ctx);
+ $ENV{GIT_INDEX_FILE} = "$tmpdir/lindex";
+ ($inpipe, $ctx) =
+ $repo->command_input_pipe(qw(update-index -z --index-info));
+ print($inpipe $lindex);
+ $repo->command_close_pipe($inpipe, $ctx);
+
+ my $rc = system('git', 'checkout-index', '--all', "--prefix=$ldir/");
+ exit_cleanup($tmpdir, $rc) if $rc != 0;
+
+ $ENV{GIT_INDEX_FILE} = "$tmpdir/rindex";
+ ($inpipe, $ctx) =
+ $repo->command_input_pipe(qw(update-index -z --index-info));
+ print($inpipe $rindex);
+ $repo->command_close_pipe($inpipe, $ctx);
+
+ $rc = system('git', 'checkout-index', '--all', "--prefix=$rdir/");
+ exit_cleanup($tmpdir, $rc) if $rc != 0;
+
+ # If $GIT_DIR was explicitly set just for the update/checkout
+ # commands, then it should be unset before continuing.
+ delete($ENV{GIT_DIR}) if ($must_unset_git_dir);
+ delete($ENV{GIT_INDEX_FILE});
+
+ # Changes in the working tree need special treatment since they are
+ # not part of the index
+ for my $file (@working_tree) {
+ my $dir = dirname($file);
+ unless (-d "$rdir/$dir") {
+ mkpath("$rdir/$dir") or
+ exit_cleanup($tmpdir, 1);
+ }
+ if ($symlinks) {
+ symlink("$workdir/$file", "$rdir/$file") or
+ exit_cleanup($tmpdir, 1);
+ } else {
+ copy("$workdir/$file", "$rdir/$file") or
+ exit_cleanup($tmpdir, 1);
+
+ my $mode = stat("$workdir/$file")->mode;
+ chmod($mode, "$rdir/$file") or
+ exit_cleanup($tmpdir, 1);
+ }
+ }
+
+ # Changes to submodules require special treatment. This loop writes a
+ # temporary file to both the left and right directories to show the
+ # change in the recorded SHA1 for the submodule.
+ for my $path (keys %submodule) {
+ my $ok;
+ if (defined($submodule{$path}{left})) {
+ $ok = write_to_file("$ldir/$path",
+ "Subproject commit $submodule{$path}{left}");
}
- if ($arg eq '-h') {
- usage();
+ if (defined($submodule{$path}{right})) {
+ $ok = write_to_file("$rdir/$path",
+ "Subproject commit $submodule{$path}{right}");
}
- push @command, $arg;
+ exit_cleanup($tmpdir, 1) if not $ok;
}
- if ($prompt eq 'yes') {
- $ENV{GIT_DIFFTOOL_PROMPT} = 'true';
- } elsif ($prompt eq 'no') {
- $ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
+
+ # Symbolic links require special treatment. The standard "git diff"
+ # shows only the link itself, not the contents of the link target.
+ # This loop replicates that behavior.
+ for my $path (keys %symlink) {
+ my $ok;
+ if (defined($symlink{$path}{left})) {
+ $ok = write_to_file("$ldir/$path",
+ $symlink{$path}{left});
+ }
+ if (defined($symlink{$path}{right})) {
+ $ok = write_to_file("$rdir/$path",
+ $symlink{$path}{right});
+ }
+ exit_cleanup($tmpdir, 1) if not $ok;
}
- return @command
+
+ return ($ldir, $rdir, $tmpdir, @working_tree);
}
-setup_environment();
+sub write_to_file
+{
+ my $path = shift;
+ my $value = shift;
+
+ # Make sure the path to the file exists
+ my $dir = dirname($path);
+ unless (-d "$dir") {
+ mkpath("$dir") or return 0;
+ }
+
+ # If the file already exists in that location, delete it. This
+ # is required in the case of symbolic links.
+ unlink($path);
+
+ open(my $fh, '>', $path) or return 0;
+ print($fh $value);
+ close($fh);
+
+ return 1;
+}
+
+sub main
+{
+ # parse command-line options. all unrecognized options and arguments
+ # are passed through to the 'git diff' command.
+ my %opts = (
+ difftool_cmd => undef,
+ dirdiff => undef,
+ extcmd => undef,
+ gui => undef,
+ help => undef,
+ prompt => undef,
+ symlinks => $^O ne 'cygwin' &&
+ $^O ne 'MSWin32' && $^O ne 'msys',
+ tool_help => undef,
+ );
+ GetOptions('g|gui!' => \$opts{gui},
+ 'd|dir-diff' => \$opts{dirdiff},
+ 'h' => \$opts{help},
+ 'prompt!' => \$opts{prompt},
+ 'y' => sub { $opts{prompt} = 0; },
+ 'symlinks' => \$opts{symlinks},
+ 'no-symlinks' => sub { $opts{symlinks} = 0; },
+ 't|tool:s' => \$opts{difftool_cmd},
+ 'tool-help' => \$opts{tool_help},
+ 'x|extcmd:s' => \$opts{extcmd});
+
+ if (defined($opts{help})) {
+ usage(0);
+ }
+ if (defined($opts{tool_help})) {
+ print_tool_help();
+ }
+ if (defined($opts{difftool_cmd})) {
+ if (length($opts{difftool_cmd}) > 0) {
+ $ENV{GIT_DIFF_TOOL} = $opts{difftool_cmd};
+ } else {
+ print "No <tool> given for --tool=<tool>\n";
+ usage(1);
+ }
+ }
+ if (defined($opts{extcmd})) {
+ if (length($opts{extcmd}) > 0) {
+ $ENV{GIT_DIFFTOOL_EXTCMD} = $opts{extcmd};
+ } else {
+ print "No <cmd> given for --extcmd=<cmd>\n";
+ usage(1);
+ }
+ }
+ if ($opts{gui}) {
+ my $guitool = Git::config('diff.guitool');
+ if (length($guitool) > 0) {
+ $ENV{GIT_DIFF_TOOL} = $guitool;
+ }
+ }
+
+ # In directory diff mode, 'git-difftool--helper' is called once
+ # to compare the a/b directories. In file diff mode, 'git diff'
+ # will invoke a separate instance of 'git-difftool--helper' for
+ # each file that changed.
+ if (defined($opts{dirdiff})) {
+ dir_diff($opts{extcmd}, $opts{symlinks});
+ } else {
+ file_diff($opts{prompt});
+ }
+}
+
+sub dir_diff
+{
+ my ($extcmd, $symlinks) = @_;
+ my $rc;
+ my $error = 0;
+ my $repo = Git->repository();
+ my $workdir = find_worktree($repo);
+ my ($a, $b, $tmpdir, @worktree) =
+ setup_dir_diff($repo, $workdir, $symlinks);
+
+ if (defined($extcmd)) {
+ $rc = system($extcmd, $a, $b);
+ } else {
+ $ENV{GIT_DIFFTOOL_DIRDIFF} = 'true';
+ $rc = system('git', 'difftool--helper', $a, $b);
+ }
+ # If the diff including working copy files and those
+ # files were modified during the diff, then the changes
+ # should be copied back to the working tree.
+ # Do not copy back files when symlinks are used and the
+ # external tool did not replace the original link with a file.
+ for my $file (@worktree) {
+ next if $symlinks && -l "$b/$file";
+ next if ! -f "$b/$file";
+
+ my $diff = compare("$b/$file", "$workdir/$file");
+ if ($diff == 0) {
+ next;
+ } elsif ($diff == -1) {
+ my $errmsg = "warning: Could not compare ";
+ $errmsg += "'$b/$file' with '$workdir/$file'\n";
+ warn $errmsg;
+ $error = 1;
+ } elsif ($diff == 1) {
+ my $mode = stat("$b/$file")->mode;
+ copy("$b/$file", "$workdir/$file") or
+ exit_cleanup($tmpdir, 1);
+
+ chmod($mode, "$workdir/$file") or
+ exit_cleanup($tmpdir, 1);
+ }
+ }
+ if ($error) {
+ warn "warning: Temporary files exist in '$tmpdir'.\n";
+ warn "warning: You may want to cleanup or recover these.\n";
+ exit(1);
+ } else {
+ exit_cleanup($tmpdir, $rc);
+ }
+}
+
+sub file_diff
+{
+ my ($prompt) = @_;
+
+ if (defined($prompt)) {
+ if ($prompt) {
+ $ENV{GIT_DIFFTOOL_PROMPT} = 'true';
+ } else {
+ $ENV{GIT_DIFFTOOL_NO_PROMPT} = 'true';
+ }
+ }
+
+ $ENV{GIT_PAGER} = '';
+ $ENV{GIT_EXTERNAL_DIFF} = 'git-difftool--helper';
+
+ # ActiveState Perl for Win32 does not implement POSIX semantics of
+ # exec* system call. It just spawns the given executable and finishes
+ # the starting program, exiting with code 0.
+ # system will at least catch the errors returned by git diff,
+ # allowing the caller of git difftool better handling of failures.
+ my $rc = system('git', 'diff', @ARGV);
+ exit($rc | ($rc >> 8));
+}
-# ActiveState Perl for Win32 does not implement POSIX semantics of
-# exec* system call. It just spawns the given executable and finishes
-# the starting program, exiting with code 0.
-# system will at least catch the errors returned by git diff,
-# allowing the caller of git difftool better handling of failures.
-my $rc = system(generate_command());
-exit($rc | ($rc >> 8));
+main();