Merge branch 'v2-prototype' into v2-contract-wrappers-WIP

1 files changed, 58 insertions, 0 deletions

diff --git a/packages/web3-wrapper/src/utils.ts b/packages/web3-wrapper/src/utils.ts
new file mode 100644
index 000000000..d13eb9404
--- /dev/null
+++ b/packages/web3-wrapper/src/utils.ts
@@ -0,0 +1,58 @@
+import { BigNumber } from '@0xproject/utils';
+import * as _ from 'lodash';
+
+export const utils = {
+    isBigNumber(value: any): boolean {
+        const isBigNumber = _.isObject(value) && value.isBigNumber;
+        return isBigNumber;
+    },
+    convertHexToNumber(value: string): number {
+        const valueBigNumber = new BigNumber(value);
+        const valueNumber = valueBigNumber.toNumber();
+        return valueNumber;
+    },
+    convertHexToNumberOrNull(hex: string | null): number | null {
+        if (_.isNull(hex)) {
+            return null;
+        }
+        const decimal = this.convertHexToNumber(hex);
+        return decimal;
+    },
+    convertAmountToBigNumber(value: string | number | BigNumber): BigNumber {
+        const num = value || 0;
+        const isBigNumber = utils.isBigNumber(num);
+        if (isBigNumber) {
+            return num as BigNumber;
+        }
+
+        if (_.isString(num) && (num.indexOf('0x') === 0 || num.indexOf('-0x') === 0)) {
+            return new BigNumber(num.replace('0x', ''), 16);
+        }
+
+        const baseTen = 10;
+        return new BigNumber((num as number).toString(baseTen), baseTen);
+    },
+    encodeAmountAsHexString(value: string | number | BigNumber): string {
+        const valueBigNumber = utils.convertAmountToBigNumber(value);
+        const hexBase = 16;
+        const valueHex = valueBigNumber.toString(hexBase);
+
+        return valueBigNumber.lessThan(0) ? '-0x' + valueHex.substr(1) : '0x' + valueHex;
+    },
+    numberToHex(value: number): string {
+        if (!isFinite(value) && !this.isHexStrict(value)) {
+            throw new Error(`Given input ${value} is not a number.`);
+        }
+
+        const valueBigNumber = new BigNumber(value);
+        const hexBase = 16;
+        const result = valueBigNumber.toString(hexBase);
+
+        return valueBigNumber.lt(0) ? '-0x' + result.substr(1) : '0x' + result;
+    },
+    isHexStrict(hex: string | number): boolean {
+        return (
+            (_.isString(hex) || _.isNumber(hex)) && /^(-)?0x[0-9a-f]*$/i.test(_.isNumber(hex) ? hex.toString() : hex)
+        );
+    },
+};