FA-8222 / Direct manipulation / Member archive

Drag-and-drop list reordering: Reordering duplicates the dragged item instead of moving it · case 02

Reordering duplicates the dragged item instead of moving it.

Member previewVariant 2 · 3 implementations · 8 checks per implementation

Case contract

Cancellation, missing endpoints and self drops preserve order; otherwise remove the source and insert it immediately before or after the surviving target.

Why this case matters

A deterministic model of drag-and-drop list reordering; this isolates one interface invariant without requiring a browser.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
after	`["a", "b", "c", "a"]`	`["b", "c", "a"]`	Failed

MEMBER ARCHIVE

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