git-svn: ignore changeless commits when checking for a cherry-pick
Update git-svn to ignore commits that do not change the tree when it is
deciding if an svn merge ticket represents a real branch merge or just a
cherry-pick.
Consider the following integration model in the svn repository:
F---G branch1
/ \
D tag1 \ E tag2
/ \ /
A---B C trunk
branch1 is merged to trunk in commit C.
With this patch, git-svn will correctly identify branch1 as a proper merge
parent, instead of incorrectly ignoring it as a cherry-pick.
Signed-off-by: Andrew Myrick <amyrick@apple.com>
Acked-by: Sam Vilain <sam@vilain.net>
Acked-by: Eric Wong <normalperson@yhbt.net>
diff --git a/git-svn.perl b/git-svn.perl
index 650c9e5..947184a 100755
--- a/git-svn.perl
+++ b/git-svn.perl
@@ -3052,12 +3052,36 @@
for my $range ( @ranges ) {
delete @commits{_rev_list($range)};
}
+ for my $commit (keys %commits) {
+ if (has_no_changes($commit)) {
+ delete $commits{$commit};
+ }
+ }
return (keys %commits);
}
+sub has_no_changes {
+ my $commit = shift;
+
+ my @revs = split / /, command_oneline(
+ qw(rev-list --parents -1 -m), $commit);
+
+ # Commits with no parents, e.g. the start of a partial branch,
+ # have changes by definition.
+ return 1 if (@revs < 2);
+
+ # Commits with multiple parents, e.g a merge, have no changes
+ # by definition.
+ return 0 if (@revs > 2);
+
+ return (command_oneline("rev-parse", "$commit^{tree}") eq
+ command_oneline("rev-parse", "$commit~1^{tree}"));
+}
+
BEGIN {
memoize 'lookup_svn_merge';
memoize 'check_cherry_pick';
+ memoize 'has_no_changes';
}
sub parents_exclude {
