UJO documents

phil/ujo renders the code blocks of a document as <pre class="ujo-code"><code class="language-…">. Its HtmlRenderer::withCodeHighlighter() takes a highlighter — a closure from the code and its language to HTML, or null for a language it does not know — and Highlighter::highlight() has that shape:

use Phil\Highlight\Highlighter;
use Phil\Ujo\Html\HtmlRenderer;

$renderer = HtmlRenderer::default()->withCodeHighlighter(Highlighter::default()->highlight(...));

Neither library depends on the other. The renderer keeps the highlighted HTML only when it holds nothing but the code's text, escaped, inside <span class="…"> elements; any other HTML falls back to the escaped code, so the renderer stays purified by construction. A block with no language, or with one the highlighter does not know, is written as escaped text with its language-… class, for the highlight controller of phil/ux-bundle to try in the browser. Give the renderer highlight() without LineOptions: the numbers of lines and the annotations taken out change the text, and the renderer would fall back to the escaped code.

Through a purifier

phil/markup's SanitizerPurifier drops classes, but for those of code: language-… on code at every level, and hl-… on span at the levels that keep spans. Highlighted HTML purified at the all level keeps its colours; at forum the spans go and the text stays.