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Character references such as 	 and   were trimmed as literal text, so a leading encoded tab or space left an empty first info word and dropped the language class. Decode first (matching cmark), then trim. Fixes commonmark#255
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Summary
Fenced code info strings are unescaped before they are trimmed, so a leading
	or is treated as whitespace and the first word is still used as the language class (language-js).Adds the nine examples from #255 to
test/regression.txt.Unescape, then
String.prototype.trim()(the trim already used on this line). Alternative: ASCII-only trim after unescape (as inparseInlines), or skip empty first words in the HTML renderer.The first two cases are the ones @jgm called buggy, and cmark is the cited correct behaviour: decode character references, then trim. Keeping
.trim()matches this call site instead of introducing a new whitespace rule. Can switch to the ASCII-only trim fromparseInlinesif you want only spaces and tabs removed after decode.Test plan
npm test(744 passed, including new#255example)npm run lint```	js/``` js