The current TOC algorithm says, in C.3.4.5.2.

If current_toc_node["name"] is an empty string:

However, the latest spec has changed, in C.3.4.4 the initialization of the current_toc_node to null everywhere, so the case of an empty string at that place isn't happening. Shouldn't it say"

If current_toc_node["name"] is null

Note that if this is so, the whole of that part can be simplified, because null is set explicitly.

(By setting the algorithm to what it says in the text, at least my implementation failed on tests c2.ignored.{02,03,04}.)