If the title of a trail or trail-member changes, rebuild affected pages

[ikiwiki.git] / IkiWiki / Plugin / trail.pm

diff --git a/IkiWiki/Plugin/trail.pm b/IkiWiki/Plugin/trail.pm
index cf0f0a15e874aa672ba5a9eff09859e3e6b1343a..b1bb6d5b532fb25120f6da1d4a371e43e04cfb72 100644 (file)
--- a/IkiWiki/Plugin/trail.pm
+++ b/IkiWiki/Plugin/trail.pm
@@ -62,12 +62,20 @@ sub getsetup () {
                },
 }
 
+# Cache of pages' old titles, so we can tell whether they changed
+my %old_trail_titles;
+
 sub needsbuild (@) {
        my $needsbuild=shift;
+
        foreach my $page (keys %pagestate) {
                if (exists $pagestate{$page}{trail}) {
                        if (exists $pagesources{$page} &&
                            grep { $_ eq $pagesources{$page} } @$needsbuild) {
+                               # Remember its title, so we can know whether
+                               # it changed.
+                               $old_trail_titles{$page} = title_of($page);
+
                                # Remove state, it will be re-added
                                # if the preprocessor directive is still
                                # there during the rebuild. {item} is the
@@ -78,6 +86,7 @@ sub needsbuild (@) {
                        }
                }
        }
+
        return $needsbuild;
 }
 
@@ -230,6 +239,12 @@ sub trails_differ {
                if (! exists $new->{$trail}) {
                        return 1;
                }
+
+               if (exists $old_trail_titles{$trail} &&
+                       title_of($trail) ne $old_trail_titles{$trail}) {
+                       return 1;
+               }
+
                my ($old_p, $old_n) = @{$old->{$trail}};
                my ($new_p, $new_n) = @{$new->{$trail}};
                $old_p = "" unless defined $old_p;
@@ -239,9 +254,20 @@ sub trails_differ {
                if ($old_p ne $new_p) {
                        return 1;
                }
+
+               if (exists $old_trail_titles{$old_p} &&
+                       title_of($old_p) ne $old_trail_titles{$old_p}) {
+                       return 1;
+               }
+
                if ($old_n ne $new_n) {
                        return 1;
                }
+
+               if (exists $old_trail_titles{$old_n} &&
+                       title_of($old_n) ne $old_trail_titles{$old_n}) {
+                       return 1;
+               }
        }
 
        foreach my $trail (keys %$new) {
@@ -359,6 +385,12 @@ sub prerender {
 sub build_affected {
        my %affected;
 
+       # In principle we might not have done this yet, although in practice
+       # at least the trail itself has probably changed, and its template
+       # almost certainly contains TRAILS or TRAILLOOP, triggering our
+       # prerender as a side-effect.
+       prerender();
+
        foreach my $member (keys %rebuild_trail_members) {
                $affected{$member} = sprintf(gettext("building %s, its previous or next page has changed"), $member);
        }