3 # REuse REcorded REsolve. This tool records a conflicted automerge
4 # result and its hand resolution, and helps to resolve future
5 # automerge that results in the same conflict.
7 # To enable this feature, create a directory 'rr-cache' under your
14 my $git_dir = $::ENV
{GIT_DIR
} || ".git";
15 my $rr_dir = "$git_dir/rr-cache";
16 my $merge_rr = "$git_dir/rr-cache/MERGE_RR";
27 open $in, "<$merge_rr" or die "$!: $merge_rr";
30 my ($name, $path) = /^([0-9a-f]{40})\t(.*)$/s;
31 $merge_rr{$path} = $name;
38 open $out, ">$merge_rr" or die "$!: $merge_rr";
39 for my $path (sort keys %merge_rr) {
40 my $name = $merge_rr{$path};
41 print $out "$name\t$path\0";
46 sub compute_conflict_name
{
50 open $in, "<$path" or die "$!: $path";
52 my $sha1 = Digest
->new("SHA-1");
62 elsif (/^>>>>>>> .*/) {
64 $one = join('', @
{$side[0]});
65 $two = join('', @
{$side[1]});
67 ($one, $two) = ($two, $one);
78 elsif (defined $side[1]) {
86 return ($sha1->hexdigest, $hunk);
90 my ($path, $name) = @_;
93 open $in, "<$path" or die "$!: $path";
94 open $out, ">$name" or die "$!: $name";
100 elsif (/^=======$/) {
103 elsif (/^>>>>>>> .*/) {
105 $one = join('', @
{$side[0]});
106 $two = join('', @
{$side[1]});
108 ($one, $two) = ($two, $one);
110 print $out "<<<<<<<\n";
112 print $out "=======\n";
114 print $out ">>>>>>>\n";
120 elsif (defined $side[1]) {
121 push @
{$side[1]}, $_;
124 push @
{$side[0]}, $_;
134 my $pid = open($in, '-|');
135 die "$!" unless defined $pid;
137 exec(qw(git ls-files -z -u)) or die "$!: ls-files";
143 my ($mode, $sha1, $stage, $path) =
144 /^([0-7]+) ([0-9a-f]{40}) ([123])\t(.*)$/s;
145 $path{$path} |= (1 << $stage);
148 while (my ($path, $status) = each %path) {
149 if ($status == 14) { push @path, $path; }
155 my ($name, $path) = @_;
156 record_preimage
($path, "$rr_dir/$name/thisimage");
157 unless (system('merge', map { "$rr_dir/$name/${_}image" }
158 qw(this pre post))) {
160 open $in, "<$rr_dir/$name/thisimage" or
161 die "$!: $name/thisimage";
163 open $out, ">$path" or die "$!: $path";
164 while (<$in>) { print $out $_; }
172 -d
"$rr_dir" || exit(0);
175 my %conflict = map { $_ => 1 } find_conflict
();
177 # MERGE_RR records paths with conflicts immediately after merge
178 # failed. Some of the conflicted paths might have been hand resolved
179 # in the working tree since then, but the initial run would catch all
180 # and register their preimages.
182 for my $path (keys %conflict) {
183 # This path has conflict. If it is not recorded yet,
184 # record the pre-image.
185 if (!exists $merge_rr{$path}) {
186 my ($name, $hunk) = compute_conflict_name
($path);
188 $merge_rr{$path} = $name;
189 if (! -d
"$rr_dir/$name") {
190 mkpath
("$rr_dir/$name", 0, 0777);
191 print STDERR
"Recorded preimage for '$path'\n";
192 record_preimage
($path, "$rr_dir/$name/preimage");
197 # Now some of the paths that had conflicts earlier might have been
198 # hand resolved. Others may be similar to a conflict already that
199 # was resolved before.
201 for my $path (keys %merge_rr) {
202 my $name = $merge_rr{$path};
204 # We could resolve this automatically if we have images.
205 if (-f
"$rr_dir/$name/preimage" &&
206 -f
"$rr_dir/$name/postimage") {
207 if (merge
($name, $path)) {
208 print STDERR
"Resolved '$path' using previous resolution.\n";
209 # Then we do not have to worry about this path
211 delete $merge_rr{$path};
216 # Let's see if we have resolved it.
217 (undef, my $hunk) = compute_conflict_name
($path);
220 print STDERR
"Recorded resolution for '$path'.\n";
221 copy
($path, "$rr_dir/$name/postimage");
222 # And we do not have to worry about this path anymore.
223 delete $merge_rr{$path};
226 # Write out the rest.