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
  10 my @src;
  11 my %src;
  12 sub andjoin {
  13         my ($label, $labels, $stuff) = @_;
  14         my $l = scalar @$stuff;
  15         my $m = '';
  16         if ($l == 0) {
  17                 return ();
  18         }
  19         if ($l == 1) {
  20                 $m = "$label$stuff->[0]";
  21         }
  22         else {
  23                 $m = ("$labels" .
  24                       join (', ', @{$stuff}[0..$l-2]) .
  25                       " and $stuff->[-1]");
  26         }
  27         return ($m);
  28 }
  29
  30 sub repoconfig {
  31         my ($val) = qx{git-repo-config --get merge.summary};
  32         return $val;
  33 }
  34
  35 sub current_branch {
  36         my ($bra) = qx{git-symbolic-ref HEAD};
  37         chomp($bra);
  38         $bra =~ s|^refs/heads/||;
  39         if ($bra ne 'master') {
  40                 $bra = " into $bra";
  41         } else {
  42                 $bra = "";
  43         }
  44         return $bra;
  45 }
  46
  47 sub shortlog {
  48         my ($tip) = @_;
  49         my @result;
  50         foreach ( qx{git-log --topo-order --pretty=oneline $tip ^HEAD} ) {
  51                 s/^[0-9a-f]{40}\s+//;
  52                 push @result, $_;
  53         }
  54         die "git-log failed\n" if $?;
  55         return @result;
  56 }
  57
  58 my @origin = ();
  59 while (<>) {
  60         my ($bname, $tname, $gname, $src, $sha1, $origin);
  61         chomp;
  62         s/^([0-9a-f]*)  //;
  63         $sha1 = $1;
  64         next if (/^not-for-merge/);
  65         s/^     //;
  66         if (s/ of (.*)$//) {
  67                 $src = $1;
  68         } else {
  69                 # Pulling HEAD
  70                 $src = $_;
  71                 $_ = 'HEAD';
  72         }
  73         if (! exists $src{$src}) {
  74                 push @src, $src;
  75                 $src{$src} = {
  76                         BRANCH => [],
  77                         TAG => [],
  78                         GENERIC => [],
  79                         # &1 == has HEAD.
  80                         # &2 == has others.
  81                         HEAD_STATUS => 0,
  82                 };
  83         }
  84         if (/^branch (.*)$/) {
  85                 $origin = $1;
  86                 push @{$src{$src}{BRANCH}}, $1;
  87                 $src{$src}{HEAD_STATUS} |= 2;
  88         }
  89         elsif (/^tag (.*)$/) {
  90                 $origin = $_;
  91                 push @{$src{$src}{TAG}}, $1;
  92                 $src{$src}{HEAD_STATUS} |= 2;
  93         }
  94         elsif (/^HEAD$/) {
  95                 $origin = $src;
  96                 $src{$src}{HEAD_STATUS} |= 1;
  97         }
  98         else {
  99                 push @{$src{$src}{GENERIC}}, $_;
 100                 $src{$src}{HEAD_STATUS} |= 2;
 101                 $origin = $src;
 102         }
 103         if ($src eq '.' || $src eq $origin) {
 104                 $origin =~ s/^'(.*)'$/$1/;
 105                 push @origin, [$sha1, "$origin"];
 106         }
 107         else {
 108                 push @origin, [$sha1, "$origin of $src"];
 109         }
 110 }
 111
 112 my @msg;
 113 for my $src (@src) {
 114         if ($src{$src}{HEAD_STATUS} == 1) {
 115                 # Only HEAD is fetched, nothing else.
 116                 push @msg, $src;
 117                 next;
 118         }
 119         my @this;
 120         if ($src{$src}{HEAD_STATUS} == 3) {
 121                 # HEAD is fetched among others.
 122                 push @this, andjoin('', '', ['HEAD']);
 123         }
 124         push @this, andjoin("branch ", "branches ",
 125                            $src{$src}{BRANCH});
 126         push @this, andjoin("tag ", "tags ",
 127                            $src{$src}{TAG});
 128         push @this, andjoin("commit ", "commits ",
 129                             $src{$src}{GENERIC});
 130         my $this = join(', ', @this);
 131         if ($src ne '.') {
 132                 $this .= " of $src";
 133         }
 134         push @msg, $this;
 135 }
 136
 137 my $into = current_branch();
 138
 139 print "Merge ", join("; ", @msg), $into, "\n";
 140
 141 if (!repoconfig) {
 142         exit(0);
 143 }
 144
 145 # We limit the merge message to the latst 20 or so per each branch.
 146 my $limit = 20;
 147
 148 for (@origin) {
 149         my ($sha1, $name) = @$_;
 150         my @log = shortlog($sha1);
 151         if ($limit + 1 <= @log) {
 152                 print "\n* $name: (" . scalar(@log) . " commits)\n";
 153         }
 154         else {
 155                 print "\n* $name:\n";
 156         }
 157         my $cnt = 0;
 158         for my $log (@log) {
 159                 if ($limit < ++$cnt) {
 160                         print "  ...\n";
 161                         last;
 162                 }
 163                 print "  $log";
 164         }
 165 }