Calculation audit (brief config: 30 MPG imperial, £60 fill-up, baseline
Rontec Shelf 171.9p at 0.4 mi):
- One mile<->kilometre constant pair (kilometresPerMile 1.609344,
metresPerMile 1609.344) replaces the mixed 1609.34 / 0.621371 / 1.60934
used in the savings path. Effect ~2 ppm (invisible), but the conversions
are now auditable in one place.
- New FuelSavingsCalculationAuditTests (20 deterministic tests, no live
MKDirections) pins the brief's three stations - Tesco 170.9p/2.0 mi,
MFG Hare & Hounds 172.9p/2.8 mi, PGG Napoleon 171.9p/2.8 mi - plus
imperial-vs-US gallon, MPG and budget scaling, the break-even tolerance
boundary, the nearer-candidate clamp, route-unavailable, mixed-basis
estimates and display-rounding boundaries.
- Formula unchanged, and verified correct: fixed quantity (budget / baseline
price), pump saving, round-trip extra distance clamped at zero, travel fuel
priced at the candidate station, +/-5p break even, baseline labelled
"Closest station", sorting on the unrounded net saving. The brief's "£0.18"
for Tesco is the rounded 1 dp extra-distance caption (2.02-2.05 mi reads as
"2.0 mi"), not a rounding bug in the money.
UI (uncommitted since d7a0ecb):
- Done bar drawn in the bottom safe area from keyboard notifications:
.toolbar(placement: .keyboard) is device-dependent (present on the 15 Pro,
absent on the SE on the same iOS build).
- Favourite star in the More-info heading, wired to the same fuel-scoped
toggle as the listing rows at all three call sites.
- CHEAPEST/TOP badge moved above the price so it reads as part of it.
- Listing rows carry the real session fill-up amount instead of a hard zero
(the compact banner does not print it today; a future row layout would).
153 tests, 0 failures. Simulator and device builds succeed.
Optional Fuel Savings feature (off by default): vehicle MPG in UK imperial gallons, fill amount in pounds or litres, persisted through the existing keychain/app-group store. Ranks the WHOLE station pool by estimated net saving (fuel-price saving at each pump minus the extra return-trip driving cost) using MapKit road distances with a straight-line fallback marked (est.).
The closest station with a valid price for the selected fuel is the comparison baseline and is labelled "Closest station"; other rows read "Save £X.XX after travel" / "£X.XX worse off after travel" / "Break even". Labels live in the shared model so they are unit-tested. The TOP badge still marks the cheapest pump price and reads "CHEAPEST" when the list is ranked by net saving.
Road routing now prioritises the Worth-the-Drive candidates plus the baseline and merges cache entries instead of replacing them, so far-out stations get real routes rather than permanent straight-line estimates. Numeric fields gain a Done button above the keypad (decimalPad has no Return key); the fill-up control is hidden unless the feature is configured; Favourites shares one session fill amount with the station list. 131 tests.
FuelBoard Contributor
FuelBoard Contributor