FA-82378 / Chess move legality / Member archive

Queen moves only like a rook · case 03

A queen is never offered diagonal moves.

Member previewVariant 3 · 3 implementations · 8 checks per implementation

Case contract

Input: {"board", "from": square of a rook, bishop or queen}. Return the sorted pseudo-legal destinations: walk each ray until the edge; an empty square is added, an enemy piece is added and ends the ray, a friendly piece ends the ray without being added.

Why this case matters

Move validators gate every move in engines, servers and arbiters; accepting an illegal move or rejecting a legal one corrupts the game record.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
queen open	`["a5", "b5", "c5", "d1", "d2", "d3", "d4", "d6", "e5", "f5", "g5", "h5"]`	`["a2", "a5", "a8", "b3", "b5", "b7", "c4", "c5", "c6", "d1", "d2", "d3", "d4", "d6", "e4", "e5", "e6", "f3", "f5", "f7", "g2", "g5", "g8", "h1", "h5"]`	Failed

MEMBER ARCHIVE

The complete case is available to members.

This record includes three runnable implementations, regression fixtures, execution results, and source hashes.

Member access is invitation-based. Sign in with your invited account to inspect the sources.