FA-21419 / Assistive announcements / Member archive

Backspace announcement includes one extra preceding character · case 04

The announcement trace violates the stated edit-narration contract.

Member previewVariant 4 · 3 implementations · 8 checks per implementation

Case contract

Document announcement state stores text and a cursor. Insert inserts at clamped cursor and announces inserted span. Backspace removes up to count before cursor and announces removed span in original order. Delete removes after cursor without moving it. Move clamps cursor. Replace range uses sorted clamped endpoints, announces old/new, moves cursor to replacement end. Undo restores text and cursor from last mutating edit and announces restored text. Silent toggles suppress cues but not state or undo. Return cues,text,cursor.

Why this case matters

Deterministic controlled model of assistive announcement delivery.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
trace-1	`[[["insert", "abcdabcdabcdabcd"], ["insert", "XY"], ["remove", "bXY"], ["undo", "abXYcdabcdabcdabcd"], ["undo", "abcdabcdabcdabcd"]], "abcdabcdabcdabcd", 2]`	`[[["insert", "abcdabcdabcdabcd"], ["insert", "XY"], ["remove", "XY"], ["undo", "abXYcdabcdabcdabcd"], ["undo", "abcdabcdabcdabcd"]], "abcdabcdabcdabcd", 2]`	Failed

MEMBER ARCHIVE

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