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Fix crash during block math parsing #142

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Merged
LiYanan2004 merged 1 commit into from
Feb 28, 2026
Merged

Fix crash during block math parsing #142

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2 changes: 1 addition & 1 deletion Sources/MarkdownView/Renderers/Math/MathFirstMarkdownViewRenderer.swift
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Original file line number Diff line number Diff line change
Expand Up @@ -18,7 +18,7 @@ struct MathFirstMarkdownViewRenderer: MarkdownViewRenderer {

var extractor = ParsingRangesExtractor()
extractor.visit(content.parse(options: ParseOptions().union(.parseBlockDirectives)))
for range in extractor.parsableRanges(in: rawText) {
for range in extractor.parsableRanges(in: rawText).reversed() {
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Copilot AI Feb 28, 2026

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This change fixes a crash scenario (math blocks + code blocks). Please add a regression test that renders markdown containing both a fenced code block and a display-math block to ensure MathFirstMarkdownViewRenderer no longer crashes when processing multiple parsable segments.

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let segment = rawText[range]
let segmentParser = MathParser(text: segment)
Comment on lines +21 to 23
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Copilot AI Feb 28, 2026

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Even with iterating ranges in reverse, this loop still reuses precomputed Range<String.Index> values after mutating rawText (via replaceSubrange). Swift String mutations can invalidate existing indices/ranges, which can still lead to crashes in edge cases. Consider capturing ranges as integer offsets (e.g., UTF-16 offsets) and recreating fresh String.Index values on the current rawText before slicing/replacing, or perform replacements on a copied String segment and then splice the segment back into rawText.

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for math in segmentParser.mathRepresentations.reversed() where !math.kind.inline {
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