FA-62487 / Tax bracket computation / Member archive

An unrecognised credit kind is silently ignored · case 02

A mistyped credit code disappears from the computation without an error.

Member previewVariant 2 · 3 implementations · 6 checks per implementation

Case contract

solve(tax, credits): tax is integer cents >= 0; credits is a list of [kind, cents] with kind 'nonref' (nonrefundable, unused part lost), 'carry' (nonrefundable, unused part carried forward) or 'ref' (refundable). Unknown kinds return 'ERR:kind'. Apply all nonref credits first (limited to the remaining tax), then carry credits (limited to what remains), then refundable credits in full (a negative result is a refund). Return [final_tax, carryforward].

Why this case matters

Tax computations hinge on which slice, threshold, ordering and rounding rule applies at each step; a misplaced boundary silently misstates liabilities.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
regression unknown-credit-kind 1	`[-50, 1689]`	`"ERR:kind"`	Failed

MEMBER ARCHIVE

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