FA-85423 / Ride-hailing fare and surge pricing / Member archive

Voided quote recomputed from the estimated distance · case 03

A rider who lengthened the trip pays for the estimated distance.

Member previewVariant 3 · 3 implementations · 7 checks per implementation

Case contract

An upfront quote is honored unless (checked in this order) the destination changed, stops were added, actual distance exceeds the estimate by more than 25% (m*4 > est*5), or actual time exceeds it by more than 50% (s*2 > est*3). Otherwise-recomputed fares use actual meters and seconds: base + half-up(m*per_km/1000) + half-up(s*per_min/60). Return the charge and the reason code.

Why this case matters

Ride-hailing prices are computed per trip at scale; ordering, unit and boundary slips become systematic over- or under-charging.

One recorded failure

Sample boundary fixture

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

Boundary fixture	Actual	Expected	Outcome
regression: recompute inputs	`{"charged": 1901, "reason": "distance"}`	`{"charged": 2151, "reason": "distance"}`	Failed

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