git-svn: convert SVN 1.5+ / svnmerge.py svn:mergeinfo props to parents

This feature is long overdue; convert SVN's merge representation to git's
as revisions are imported.  This works by converting the list of revisions
in each line of the svn:mergeinfo into git revision ranges, and then
checking the latest of each of these revision ranges for A) being new and
B) now being completely merged.

Signed-off-by: Sam Vilain <sam.vilain@catalyst.net.nz>
Acked-by: Eric Wong <normalperson@yhbt.net>

diff --git a/git-svn.perl b/git-svn.perl
index 1b918aef714998f28aee3c8e754c3b02ec9201d1..6a3b501d24ebaa50e297511ccf0b18e3bbd2bb16 100755 (executable)
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -2918,6 +2918,93 @@ sub find_extra_svk_parents {
        }
 }
 
+# note: this function should only be called if the various dirprops
+# have actually changed
+sub find_extra_svn_parents {
+       my ($self, $ed, $mergeinfo, $parents) = @_;
+       # aha!  svk:merge property changed...
+
+       # We first search for merged tips which are not in our
+       # history.  Then, we figure out which git revisions are in
+       # that tip, but not this revision.  If all of those revisions
+       # are now marked as merge, we can add the tip as a parent.
+       my @merges = split "\n", $mergeinfo;
+       my @merge_tips;
+       my @merged_commit_ranges;
+       my $url = $self->rewrite_root || $self->{url};
+       for my $merge ( @merges ) {
+               my ($source, $revs) = split ":", $merge;
+               my $path = $source;
+               $path =~ s{^/}{};
+               my $gs = Git::SVN->find_by_url($url.$source, $url, $path);
+               if ( !$gs ) {
+                       warn "Couldn't find revmap for $url$source\n";
+                       next;
+               }
+               my @ranges = split ",", $revs;
+               my ($tip, $tip_commit);
+               # find the tip
+               for my $range ( @ranges ) {
+                       my ($bottom, $top) = split "-", $range;
+                       $top ||= $bottom;
+                       my $bottom_commit =
+                               $gs->rev_map_get($bottom, $self->ra_uuid) ||
+                               $gs->rev_map_get($bottom+1, $self->ra_uuid);
+                       my $top_commit =
+                               $gs->rev_map_get($top, $self->ra_uuid);
+
+                       unless ($top_commit and $bottom_commit) {
+                               warn "W:unknown path/rev in svn:mergeinfo "
+                                       ."dirprop: $source:$range\n";
+                               next;
+                       }
+
+                       push @merged_commit_ranges,
+                               "$bottom_commit..$top_commit";
+
+                       if ( !defined $tip or $top > $tip ) {
+                               $tip = $top;
+                               $tip_commit = $top_commit;
+                       }
+               }
+               unless (!$tip_commit or
+                               grep { $_ eq $tip_commit } @$parents ) {
+                       push @merge_tips, $tip_commit;
+               } else {
+                       push @merge_tips, undef;
+               }
+       }
+       for my $merge_tip ( @merge_tips ) {
+               my $spec = shift @merges;
+               next unless $merge_tip;
+               my @cmd = ('rev-list', "-1", $merge_tip,
+                          "--not", @$parents );
+               my ($msg_fh, $ctx) = command_output_pipe(@cmd);
+               my $new;
+               while ( <$msg_fh> ) {
+                       $new=1;last;
+               }
+               command_close_pipe($msg_fh, $ctx);
+               if ( $new ) {
+                       push @cmd, @merged_commit_ranges;
+                       my ($msg_fh, $ctx) = command_output_pipe(@cmd);
+                       my $unmerged;
+                       while ( <$msg_fh> ) {
+                               $unmerged=1;last;
+                       }
+                       command_close_pipe($msg_fh, $ctx);
+                       if ( $unmerged ) {
+                               warn "W:svn cherry-pick ignored ($spec)\n";
+                       } else {
+                               warn
+                                 "Found merge parent (svn:mergeinfo prop): ",
+                                 $merge_tip, "\n";
+                               push @$parents, $merge_tip;
+                       }
+               }
+       }
+}
+
 sub make_log_entry {
        my ($self, $rev, $parents, $ed) = @_;
        my $untracked = $self->get_untracked($ed);
@@ -2930,6 +3017,12 @@ sub make_log_entry {
                        $self->find_extra_svk_parents
                                ($ed, $props->{"svk:merge"}, \@parents);
                }
+               if ( $props->{"svn:mergeinfo"} ) {
+                       $self->find_extra_svn_parents
+                               ($ed,
+                                $props->{"svn:mergeinfo"},
+                                \@parents);
+               }
        }
 
        open my $un, '>>', "$self->{dir}/unhandled.log" or croak $!;

diff --git a/t/t9151-svn-mergeinfo.sh b/t/t9151-svn-mergeinfo.sh
new file mode 100644 (file)
index 0000000..7eb36e5
--- /dev/null
+++ b/t/t9151-svn-mergeinfo.sh
@@ -0,0 +1,21 @@
+#!/bin/sh
+#
+# Copyright (c) 2007, 2009 Sam Vilain
+#
+
+test_description='git-svn svn mergeinfo properties'
+
+. ./lib-git-svn.sh
+
+test_expect_success 'load svn dump' "
+       svnadmin load -q '$rawsvnrepo' < '../t9151/svn-mergeinfo.dump' &&
+       git svn init --minimize-url -R svnmerge \
+         -T trunk -b branches '$svnrepo' &&
+       git svn fetch --all
+       "
+
+test_expect_success 'svn merges were represented coming in' "
+       [ `git cat-file commit HEAD | grep parent | wc -l` -eq 2 ]
+       "
+
+test_done