Optimize TextLayoutEngine wrap loop#8
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Port lightning-js/renderer#787: - Replace shift/unshift on words/spaces arrays with index pointers and a pendingWord string to avoid O(n^2) array reshuffling on long lines. - Replace spread push of wrappedLine with a for loop. - Guard against infinite loop when maxWidth is smaller than a single glyph plus the overflow suffix; force overflowSuffix (or single char) and end the line as truncated. Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Summary
Ports lightning-js/renderer#787 — a perf + correctness fix for
wrapLine.words.shift()/words.unshift(remainingWord)/spaces.shift()with index pointers (wordIdx,spaceIdx) and apendingWordstring.shift/unshiftare O(n); for long lines with many wraps this was O(n²) per word.wrappedLines.push(...wrappedLine)with aforloop. Avoids spread-arg stack risk and is faster on V8 for non-trivial lengths.maxWidthis smaller than a single glyph plus the overflow suffix. Previously, iftruncateWordreturnedword.length === 0with a remainder, the remainder was unshifted and the loop spun forever. The fix forces anoverflowSuffix(or single char fallback) and ends the line as truncated.Test plan
TextLayoutEnginetests pass (21/21)maxWidth < glyph + suffix width)🤖 Generated with Claude Code