FA-11627 / Compression format semantics / Member archive

Burrows-Wheeler inversion ignores the primary row · case 02

Burrows-Wheeler inversion ignores the primary row.

Member previewVariant 2 · 3 implementations · 6 checks per implementation

Case contract

Invert a toy BWT by reconstructing sorted rotations from the last column and selecting the supplied zero-based primary row. Empty last column yields empty text.

Why this case matters

A small offline codec model isolates a compression-specific failure without external files or libraries.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
middle primary	`"aab"`	`"aba"`	Failed

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