fix(balance): sum unrounded token values for the total (iOS parity) - #1228
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The wallet total was `sum(round(each token))` — it rounded every token to cents and then summed, which drifts the total by up to a penny versus `round(sum)`. iOS (ExchangedFiat.total) sums the unrounded native values and rounds only at display, and our own aggregateAppreciation already sums unrounded — so the total was the lone divergence, showing a 1¢ difference from iOS even when every per-token balance and the appreciation matched. Sum the unrounded per-token balances and let display formatting round the total.
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Two tokens each worth $0.014 display as $0.01 apiece (sum-of-rounded = $0.02) but truly sum to $0.028 -> $0.03. Locks in the round(sum) aggregation so the per-token-rounding regression can't come back.
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Problem
A 1¢ discrepancy in the wallet total between iOS and Android, even though every per-token balance and the appreciation matched.
Root cause
SelectTokenViewModel.State.totalBalancecomputedset.map { it.balance.rounded() }.sum()— it rounded each token to cents before summing (sum(round(x))). That drifts fromround(sum(x))by up to a penny once the sub-cent remainders accumulate.iOS is
round(sum):Session.totalBalance→ExchangedFiat.total(rate:)sums each token's unrounded native value and rounds only at display. Android's ownaggregateAppreciationalready sums unrounded (which is why appreciation matched). So the per-token round intotalBalancewas the lone divergence.Fix
Sum the unrounded per-token balances (
set.map { it.balance }.sum()) and let display formatting round the total — matching iOS and our appreciation aggregation. One line; also removes the now-unusedroundedimport.This single computed property backs both the v1 (
BalanceScreenContent) and v2 (WalletScreenContent) balance headers, so both are fixed.Test Plan
:apps:flipcash:shared:tokenscompiles.