64 lines
1.8 KiB
TypeScript

import { BigNumber } from '@0x/utils';
import * as crypto from 'crypto';
import * as ethUtil from 'ethereumjs-util';
import { constants } from './constants';
const { WORD_LENGTH } = constants;
/**
* Concatenate all arguments as a hex string.
*/
export function hexConcat(...args: Array<string | number | Buffer>): string {
return ethUtil.bufferToHex(Buffer.concat(args.map(h => ethUtil.toBuffer(h))));
}
/**
* Generate a random hex string.
*/
export function hexRandom(size: number = WORD_LENGTH): string {
return ethUtil.bufferToHex(crypto.randomBytes(size));
}
/**
* Left-pad a hex number to a number of bytes.
*/
export function hexLeftPad(n: string | BigNumber | number, size: number = WORD_LENGTH): string {
return ethUtil.bufferToHex(ethUtil.setLengthLeft(toHex(n), size));
}
/**
* Right-pad a hex number to a number of bytes.
*/
export function hexRightPad(n: string | BigNumber | number, size: number = WORD_LENGTH): string {
return ethUtil.bufferToHex(ethUtil.setLengthRight(toHex(n), size));
}
/**
* Inverts a hex word.
*/
export function hexInvert(n: string | BigNumber | number, size: number = WORD_LENGTH): string {
const buf = ethUtil.setLengthLeft(toHex(n), size);
// tslint:disable-next-line: no-bitwise
return ethUtil.bufferToHex(Buffer.from(buf.map(b => ~b)));
}
/**
* Convert a string, a number, or a BigNumber into a hex string.
*/
export function toHex(n: string | BigNumber | number): string {
let hex = '0x00';
if (typeof n === 'number') {
hex = `0x${n.toString(16)}`;
} else if (BigNumber.isBigNumber(n)) {
hex = `0x${n.toString(16)}`;
} else {
if (/^0x/.test(n)) {
hex = n;
} else {
hex = `0x${parseInt(n, 10).toString(16)}`;
}
}
return hex;
}