git-fmt-merge-msg.perl

   1 #!/usr/bin/perl -w
   2 #
   3 # Copyright (c) 2005 Junio C Hamano
   4 #
   5 # Read .git/FETCH_HEAD and make a human readable merge message
   6 # by grouping branches and tags together to form a single line.
   7
   8 use strict;
   9 use Git;
  10 use Error qw(:try);
  11
  12 my $repo = Git->repository();
  13
  14 my @src;
  15 my %src;
  16 sub andjoin {
  17         my ($label, $labels, $stuff) = @_;
  18         my $l = scalar @$stuff;
  19         my $m = '';
  20         if ($l == 0) {
  21                 return ();
  22         }
  23         if ($l == 1) {
  24                 $m = "$label$stuff->[0]";
  25         }
  26         else {
  27                 $m = ("$labels" .
  28                       join (', ', @{$stuff}[0..$l-2]) .
  29                       " and $stuff->[-1]");
  30         }
  31         return ($m);
  32 }
  33
  34 sub repoconfig {
  35         my $val;
  36         try {
  37                 $val = $repo->command_oneline('repo-config', '--get', 'merge.summary');
  38         } catch Git::Error::Command with {
  39                 my ($E) = shift;
  40                 if ($E->value() == 1) {
  41                         return undef;
  42                 } else {
  43                         throw $E;
  44                 }
  45         };
  46         return $val;
  47 }
  48
  49 sub current_branch {
  50         my ($bra) = $repo->command_oneline('symbolic-ref', 'HEAD');
  51         $bra =~ s|^refs/heads/||;
  52         if ($bra ne 'master') {
  53                 $bra = " into $bra";
  54         } else {
  55                 $bra = "";
  56         }
  57         return $bra;
  58 }
  59
  60 sub shortlog {
  61         my ($tip) = @_;
  62         my @result;
  63         foreach ($repo->command('log', '--no-merges', '--topo-order', '--pretty=oneline', $tip, '^HEAD')) {
  64                 s/^[0-9a-f]{40}\s+//;
  65                 push @result, $_;
  66         }
  67         return @result;
  68 }
  69
  70 my @origin = ();
  71 while (<>) {
  72         my ($bname, $tname, $gname, $src, $sha1, $origin);
  73         chomp;
  74         s/^([0-9a-f]*)  //;
  75         $sha1 = $1;
  76         next if (/^not-for-merge/);
  77         s/^     //;
  78         if (s/ of (.*)$//) {
  79                 $src = $1;
  80         } else {
  81                 # Pulling HEAD
  82                 $src = $_;
  83                 $_ = 'HEAD';
  84         }
  85         if (! exists $src{$src}) {
  86                 push @src, $src;
  87                 $src{$src} = {
  88                         BRANCH => [],
  89                         TAG => [],
  90                         R_BRANCH => [],
  91                         GENERIC => [],
  92                         # &1 == has HEAD.
  93                         # &2 == has others.
  94                         HEAD_STATUS => 0,
  95                 };
  96         }
  97         if (/^branch (.*)$/) {
  98                 $origin = $1;
  99                 push @{$src{$src}{BRANCH}}, $1;
 100                 $src{$src}{HEAD_STATUS} |= 2;
 101         }
 102         elsif (/^tag (.*)$/) {
 103                 $origin = $_;
 104                 push @{$src{$src}{TAG}}, $1;
 105                 $src{$src}{HEAD_STATUS} |= 2;
 106         }
 107         elsif (/^remote branch (.*)$/) {
 108                 $origin = $1;
 109                 push @{$src{$src}{R_BRANCH}}, $1;
 110                 $src{$src}{HEAD_STATUS} |= 2;
 111         }
 112         elsif (/^HEAD$/) {
 113                 $origin = $src;
 114                 $src{$src}{HEAD_STATUS} |= 1;
 115         }
 116         else {
 117                 push @{$src{$src}{GENERIC}}, $_;
 118                 $src{$src}{HEAD_STATUS} |= 2;
 119                 $origin = $src;
 120         }
 121         if ($src eq '.' || $src eq $origin) {
 122                 $origin =~ s/^'(.*)'$/$1/;
 123                 push @origin, [$sha1, "$origin"];
 124         }
 125         else {
 126                 push @origin, [$sha1, "$origin of $src"];
 127         }
 128 }
 129
 130 my @msg;
 131 for my $src (@src) {
 132         if ($src{$src}{HEAD_STATUS} == 1) {
 133                 # Only HEAD is fetched, nothing else.
 134                 push @msg, $src;
 135                 next;
 136         }
 137         my @this;
 138         if ($src{$src}{HEAD_STATUS} == 3) {
 139                 # HEAD is fetched among others.
 140                 push @this, andjoin('', '', ['HEAD']);
 141         }
 142         push @this, andjoin("branch ", "branches ",
 143                            $src{$src}{BRANCH});
 144         push @this, andjoin("remote branch ", "remote branches ",
 145                            $src{$src}{R_BRANCH});
 146         push @this, andjoin("tag ", "tags ",
 147                            $src{$src}{TAG});
 148         push @this, andjoin("commit ", "commits ",
 149                             $src{$src}{GENERIC});
 150         my $this = join(', ', @this);
 151         if ($src ne '.') {
 152                 $this .= " of $src";
 153         }
 154         push @msg, $this;
 155 }
 156
 157 my $into = current_branch();
 158
 159 print "Merge ", join("; ", @msg), $into, "\n";
 160
 161 if (!repoconfig) {
 162         exit(0);
 163 }
 164
 165 # We limit the merge message to the latst 20 or so per each branch.
 166 my $limit = 20;
 167
 168 for (@origin) {
 169         my ($sha1, $name) = @$_;
 170         my @log = shortlog($sha1);
 171         if ($limit + 1 <= @log) {
 172                 print "\n* $name: (" . scalar(@log) . " commits)\n";
 173         }
 174         else {
 175                 print "\n* $name:\n";
 176         }
 177         my $cnt = 0;
 178         for my $log (@log) {
 179                 if ($limit < ++$cnt) {
 180                         print "  ...\n";
 181                         last;
 182                 }
 183                 print "  $log\n";
 184         }
 185 }