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Implicit level runs: run end bookkeeping · case 05

Level runs report ends one short.

Member previewVariant 5 · 3 implementations · 8 checks per implementation

Case contract

Input [resolved classes L/R/EN/AN, embedding levels]. At even levels R goes up one and AN/EN up two; at odd levels L, EN and AN go up one. Return level runs [start, end exclusive, level] of equal final levels.

Why this case matters

Mixed right-to-left and left-to-right text must resolve levels and visual order exactly, or words, numbers and carets land in the wrong place.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
regression: run end bookkeeping	`[[0, 3, 2], [4, 5, 4], [5, 6, 6], [6, 7, 4]]`	`[[0, 4, 2], [4, 5, 4], [5, 6, 6], [6, 7, 4]]`	Failed

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