allow prefixed @id attributes to allow internal linking

[schuyler1d]

This would make hash-links work, and textile footnotes, too.

In response to these forums requests:
http://support.github.com/discussions/site/2343-textile-id-attributes-not-working-anymore-in-new-wiki
and my follow-up
http://support.github.com/discussions/site/3637-textile-id-attributes-not-working-anymore-in-new-wiki

[technoweenie]

Nice. Since that's a nokogiri transformation, it should work across formats, right? What about links that point to them? Will they get the set prefix too?

[schuyler1d]

Correct -- all formats should benefit.

As long as the links that point to them are of the standard form href="#foo" rather than href="localfile.html#foo" they should get transformed. My use-case there was particularly supporting textile footnotes which create both sides, and that's covered in one of the tests on the patch. Transforming the links is done here:

schuyler1d@c22050f#L0R65

[technoweenie]

Argh, I trusted you!

  1) Failure:
test_id_prefix_added(Markup)
    [./test/test_markup.rb:516:in `compare'
     ./test/test_markup.rb:481:in `test_id_prefix_added'
     /Users/technoweenie/.rvm/gems/ruby-1.8.7-p330/gems/mocha-0.9.12/lib/mocha/integration/test_unit/ruby_version_186_and_above.rb:22:in `__send__'
     /Users/technoweenie/.rvm/gems/ruby-1.8.7-p330/gems/mocha-0.9.12/lib/mocha/integration/test_unit/ruby_version_186_and_above.rb:22:in `run']:
<"<h2 id=\"wiki-foo\">xxxx<sup class=\"footnote\"><a href=\"#wiki-fn1\">1</a></sup></h2>\n<p class=\"footnote\" id=\"wiki-fn1\"><sup>1</sup> footnote</p>"> expected but was
<"<h2 id=\"wiki-foo\">xxxx<sup class=\"footnote\" id=\"wiki-fnr1\"><a href=\"#wiki-fn1\">1</a></sup></h2>\n<p class=\"footnote\" id=\"wiki-fn1\"><a href=\"#wiki-fnr1\"><sup>1</sup></a> footnote</p>">.

It's adding an ID to the sup tag. Probably an easy fix.

[schuyler1d]

The bug is in the test. I must have an different version of RedCloth (mine is 4.2.7) which doesn't add an ID there. But, you'll notice the patch did the right thing with the footnote->context link as well, proving the patch works, anyway :-)

We can update the test to reflect your output, or I can make the test fuzzier (just do a regex on the important bits)

[technoweenie]

Oh, it's linking to a footnote. Not a big deal, I can take a look when I have some time to integrate this into GitHub.