55 lines
1.5 KiB
TypeScript
55 lines
1.5 KiB
TypeScript
import { BigNumber, SafeMathRevertErrors } from '@0x/utils';
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const MAX_UINT256 = new BigNumber(2).pow(256).minus(1);
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/**
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* Add two `uint256` values. Reverts on overflow.
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*/
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export function safeAdd(a: BigNumber, b: BigNumber): BigNumber {
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const r = a.plus(b);
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if (r.isGreaterThan(MAX_UINT256)) {
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throw new SafeMathRevertErrors.Uint256BinOpError(SafeMathRevertErrors.BinOpErrorCodes.AdditionOverflow, a, b);
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}
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return r;
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}
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/**
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* Subract two `uint256` values. Reverts on overflow.
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*/
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export function safeSub(a: BigNumber, b: BigNumber): BigNumber {
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const r = a.minus(b);
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if (r.isLessThan(0)) {
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throw new SafeMathRevertErrors.Uint256BinOpError(
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SafeMathRevertErrors.BinOpErrorCodes.SubtractionUnderflow,
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a,
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b,
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);
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}
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return r;
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}
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/**
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* Multiplies two `uint256` values. Reverts on overflow.
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*/
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export function safeMul(a: BigNumber, b: BigNumber): BigNumber {
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const r = a.times(b);
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if (r.isGreaterThan(MAX_UINT256)) {
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throw new SafeMathRevertErrors.Uint256BinOpError(
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SafeMathRevertErrors.BinOpErrorCodes.MultiplicationOverflow,
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a,
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b,
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);
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}
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return r;
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}
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/**
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* Divides two `uint256` values. Reverts on division by zero.
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*/
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export function safeDiv(a: BigNumber, b: BigNumber): BigNumber {
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if (b.isEqualTo(0)) {
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throw new SafeMathRevertErrors.Uint256BinOpError(SafeMathRevertErrors.BinOpErrorCodes.DivisionByZero, a, b);
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}
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return a.dividedToIntegerBy(b);
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}
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