Fix null pointer exception in normalizeHeaderText during undo/redo #32
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Fixed issue where undo/redo operations would crash with "Cannot read properties of null (reading '1')" error. The bug was in the normalizeHeaderText method which attempted to access match[1] and match[2] without checking if the regex match returned null. This could occur during undo/redo operations on heading blocks in certain edge cases. Added null check with fallback behavior: - If regex doesn't match, log a warning and return text as-is - This prevents the crash while still exporting the content
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Fixes #23
Problem
MarkText crashes with "TypeError: Cannot read properties of null (reading '1')" during undo/redo operations on heading blocks.
Root Cause
The
normalizeHeaderTextmethod insrc/muya/lib/utils/exportMarkdown.jsattempts to access array indices[1]and[2]from a regex match result without verifying the match succeeded. When the regex fails to match (which can happen with malformed headers during undo/redo), the code tries to access properties onnull.Solution
Added null check with fallback behavior:
Testing
Tested on macOS with multiple undo/redo operations on heading blocks. The crash no longer occurs, and content is preserved correctly.
Files Changed
src/muya/lib/utils/exportMarkdown.js- Added null safety check