Meta/cook: attempt to improve the source discovery

diff --git a/cook b/cook
index 61dfc7a8273e2b9d32446a432a52da5559946633..ebe3f215ed63f2dfed20a74937dea1db290e158c 100755 (executable)
--- a/cook
+++ b/cook
@@ -158,6 +158,7 @@ sub get_source {
        my @id = ();
        my %msgs = ();
        my @msgs = ();
+       my %children = ();
        my %source = ();
        my %skip_me = ();
 
@@ -175,15 +176,19 @@ sub get_source {
 
        # Collect parent messages that are not in the series,
        # as they are likely to be the cover letters.
+       # but of course the patch could be a reply to an
+       # ordinary message.
        for my $msg (@msgs) {
                for my $parent (@{$msgs{$msg}}) {
                        if (!exists $msgs{$parent}) {
                                $source{$parent}++;
+                               $children{$parent} ||= [];
+                               push @{$children{$parent}}, $msg;
                        }
                }
        }
 
-       reduce_sources(\@msgs, \%msgs, \%source);
+       reduce_sources(\@msgs, \%msgs, \%source, \%children);
 
        map {
                " source: <$_>";
@@ -193,10 +198,10 @@ sub get_source {
 
 sub reduce_sources {
        # Message-source specific hack
-       my ($msgs_array, $msgs_map, $src_map) = @_;
+       my ($msgs_array, $msgs_map, $src_map, $child_map) = @_;
 
-       # messages without parent, or a singleton patch
-       if ((! %$src_map && @{$msgs_array}) || (@{$msgs_array} == 1)) {
+       # a singleton
+       if (@{$msgs_array} == 1) {
                %{$src_map} = ($msgs_array->[0] => 1);
                return;
        }
@@ -213,6 +218,16 @@ sub reduce_sources {
                return;
        }
 
+       # replace a parent with its sole child
+       my %replace = ();
+       for my $src (keys %$src_map) {
+               if (@{$child_map->{$src}} == 1) {
+                       $replace{$child_map->{$src}->[0]} = 1;
+               } else {
+                       $replace{$src} = $src_map->{$src};
+               }
+       }
+       %$src_map = %replace;
 }
 
 =head1