Parser: Fix exponential recursion in two-pass HTML tag matching#840
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This pull request fixes a critical performance regression in the two-pass tag matching algorithm introduced in #795.
Documents that previously parsed in ~75ms were taking ~11 seconds (and in some cases didn't even complete in a reasonable timeframe, see #828).
The
match_tags_visitorfunction was causing double recursion by manually processing array fields through calls tomatch_tags_in_node_array(), but then returningtruewhich instructedherb_visit_nodeto also automatically traverse those same children a second time.This created an exponential explosion where each level of nesting squared the number of visits.
Resolves #828