Bug Description

If color and toc plugins are enabled and you use colored headers, those headers are never colored but sometimes are prefixed with text artifacts like "color: red".

Example: The header

# [[!color   foreground=red text="Testing"]]

would sometimes be seen in the toc as

color: redTesting

Reason for this behaviour is:

1. the color plugin uses a special syntax to preserve the color through sanitize and that syntax has a plain text component.
2. the toc plugin removes everything except plain text from headers in the toc
3. if the toc plugin is executed before the color plugin in the format hook it sees the special syntax and clobbers the toc, otherwise it just removes the color markup

The bug here is that the color plugin's special syntax does not gracefully degrade to "render nothing", which I have now fixed by putting the color bits through a value attribute instead of character data. --smcv

Solutions

There are a few possible solutions to this depending on how it should work:

1. The easiest thing would be to just add a "last" parameter to the toc plugin format hook (or "first" to the color plugin). Result: No color in tocs at all
2. Adding seven lines to toc.pm would make it preserve ALL markup in headers, color as well as html markup or markdown (emphasize for example). Execution order of the plugins would not matter at all
3. A bit more code would be necessary to just specifically preserve the color, but nothing else

I would propose implementing the second option because visual markers in headers are useful to convey additional information very fast and this information should be preserved in the toc. Example: Bug or task/project tracker with color conveying status of the bug or task.

This is really a separate feature request: copy non-<a> markup in headings into the TOC. I don't think this necessarily makes sense in general. In particular, any id attributes on child elements must not be passed through because that would make the ID non-unique. --smcv

It seems you can stuff anything into ordered lists (according to w3.orgs doku), so apart from stylistic reasons and suboptimal display of links in headers (see below) I don't see any problems with markup in the toc.

Patch

This is the proposed patch to the second solution. Tested with the latest version. It works with all markup and markdown I could think of. The only case not handled optimal is if the header is just a link and nothing else, then there is no text left for the local link, the toc links directly to a different page. Is that acceptable or not?

diff --git a/IkiWiki/Plugin/toc.pm b/IkiWiki/Plugin/toc.pm
index ac07b9a..5c2b056 100644
--- a/IkiWiki/Plugin/toc.pm
+++ b/IkiWiki/Plugin/toc.pm
@@ -57,6 +57,7 @@ sub format (@) {
    my $startlevel=($params{startlevel} ? $params{startlevel} : 0);
    my $curlevel=$startlevel-1;
    my $liststarted=0;
+   my $headercollect=0;
    my $indent=sub { "\t" x $curlevel };
    $p->handler(start => sub {
        my $tagname=shift;
@@ -107,6 +108,7 @@ sub format (@) {
            $index.=&$indent."<li class=\"L$curlevel\">".
                "<a href=\"#$anchor\">";

+           $headercollect=1;
            $p->handler(text => sub {
                $page.=join("", @_);
                $index.=join("", @_);
@@ -117,12 +119,17 @@ sub format (@) {
                    $p->handler(text => undef);
                    $p->handler(end => undef);
                    $index.="</a>\n";
+                   $headercollect=0;
+               }
+               else {
+                   $index.=join("",@_);
                }
                $page.=join("", @_);
            }, "tagname, text");
        }
        else {
            $page.=$text;
+           $index.=$text if ($headercollect);
        }
    }, "tagname, text");
    $p->handler(default => sub { $page.=join("", @_) }, "text");