gitweb: Add "next" link to commitdiff view

Add a kind of "next" view in the bottom part of navigation bar for
"commitdiff" view.

For commitdiff between two commits:
  (from: _commit_)
For commitdiff for one single parent commit:
  (parent: _commit_)
For commitdiff for one merge commit
  (merge: _commit_ _commit_ ...)
For commitdiff for root (parentless) commit
  (initial)
where _link_ denotes hyperlink. SHA1 is shortened to 7 characters on
display, everything is perhaps unnecessary esc_html on display.

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>

diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index 6714e418750d2835b9d80418daf2d90ab6ab058c..ec46b8091bac2fa890c5e7356482b0842a7d829a 100755 (executable)
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -3396,6 +3396,51 @@ sub git_commitdiff {
        if (!%co) {
                die_error(undef, "Unknown commit object");
        }
+
+       # we need to prepare $formats_nav before any parameter munging
+       my $formats_nav;
+       if ($format eq 'html') {
+               $formats_nav =
+                       $cgi->a({-href => href(action=>"commitdiff_plain",
+                                              hash=>$hash, hash_parent=>$hash_parent)},
+                               "raw");
+
+               if (defined $hash_parent) {
+                       # commitdiff with two commits given
+                       my $hash_parent_short = $hash_parent;
+                       if ($hash_parent =~ m/^[0-9a-fA-F]{40}$/) {
+                               $hash_parent_short = substr($hash_parent, 0, 7);
+                       }
+                       $formats_nav .=
+                               ' (from: ' .
+                               $cgi->a({-href => href(action=>"commitdiff",
+                                                      hash=>$hash_parent)},
+                                       esc_html($hash_parent_short)) .
+                               ')';
+               } elsif (!$co{'parent'}) {
+                       # --root commitdiff
+                       $formats_nav .= ' (initial)';
+               } elsif (scalar @{$co{'parents'}} == 1) {
+                       # single parent commit
+                       $formats_nav .=
+                               ' (parent: ' .
+                               $cgi->a({-href => href(action=>"commitdiff",
+                                                      hash=>$co{'parent'})},
+                                       esc_html(substr($co{'parent'}, 0, 7))) .
+                               ')';
+               } else {
+                       # merge commit
+                       $formats_nav .=
+                               ' (merge: ' .
+                               join(' ', map {
+                                       $cgi->a({-href => href(action=>"commitdiff",
+                                                              hash=>$_)},
+                                               esc_html(substr($_, 0, 7)));
+                               } @{$co{'parents'}} ) .
+                               ')';
+               }
+       }
+
        if (!defined $hash_parent) {
                $hash_parent = $co{'parent'} || '--root';
        }
@@ -3434,10 +3479,6 @@ sub git_commitdiff {
        if ($format eq 'html') {
                my $refs = git_get_references();
                my $ref = format_ref_marker($refs, $co{'id'});
-               my $formats_nav =
-                       $cgi->a({-href => href(action=>"commitdiff_plain",
-                                              hash=>$hash, hash_parent=>$hash_parent)},
-                               "raw");
 
                git_header_html(undef, $expires);
                git_print_page_nav('commitdiff','', $hash,$co{'tree'},$hash, $formats_nav);