fix(amount): round USDC to whole base units so the on-chain amount is an integer - #45
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Bornoz wants to merge 1 commit into
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fix(amount): round USDC to whole base units so the on-chain amount is an integer#45Bornoz wants to merge 1 commit into
Bornoz wants to merge 1 commit into
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… an integer convertUSDCToContractAmount scales a USDC amount to 6-decimal base units for the uint256 that pay(address,uint256,address) takes, but it does it in floating point: (amount * 1000000).toString(). Ordinary amounts land just under a whole unit — 2.01 becomes "2009999.9999999998", 1.005 becomes "1004999.9999999999" — and toString carries the fraction straight through. Both deposit routes pass the result as the uint256 amount, so a plain 2.01 deposit goes on-chain as a non-integer: rejected by the encoder, or truncated a base unit short. Round to the nearest base unit, which is the integer the function is meant to produce.
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convertUSDCToContractAmountturns a USDC amount into 6-decimal base units for theuint256thatpay(address,uint256,address)takes, but it scales in floating point:(amount * 1000000).toString(). Ordinary amounts land just under a whole unit —2.01becomes"2009999.9999999998",2.05"2049999.9999999998",1.005"1004999.9999999999"— and.toString()carries the fraction straight through. Around 3% of cent-precision amounts are affected.Both deposit routes then do
Number(convertUSDCToContractAmount(...))and pass the result as theuint256amount to the escrowpay()call (app/api/contracts/escrow/deposit/route.ts,.../deposit/approve/route.ts), so a plain $2.01 deposit goes on-chain as a non-integer amount — rejected by the encoder, or truncated a base unit short.Rounding to the nearest base unit is the correct fixed-point conversion and restores the integer the function is meant to produce. Verified against the current values:
2.01,2.05,4.02,1.005return fractional strings before the change and the exact base-unit integers after;tsc --noEmitandprettier --checkstay clean.Separate from #44, which fixes
parseAmount.