fix: avoid crash when moving a zero-length range#307
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antfu merged 2 commits intoJul 16, 2026
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move(start, end, index) threw a TypeError ('Cannot read properties of
undefined') when start === end, because byEnd[end] is undefined for an
empty range so reading last.next failed. remove() already treats a
zero-length range as a no-op; do the same in move().
antfu
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…h-range # Conflicts: # src/MagicString.js # test/MagicString.test.js
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Jul 16, 2026
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move()crashes with an opaqueTypeError: Cannot read properties of undefined (reading 'next')when called with a zero-length range (start === end):The reason is that for an empty range
byEnd[end]has no chunk, solastisundefinedand the subsequentlast.nextblows up.remove()already short-circuits a zero-length range as a no-op (if (start === end) return this;), so I did the same inmove()— moving nothing has no effect.I found this while fuzzing random valid operation sequences. Added a test alongside the other
moveedge cases; full suite passes.