1 files changed, 35 insertions, 7 deletions

diff --git a/packages/web3-wrapper/src/web3_wrapper.ts b/packages/web3-wrapper/src/web3_wrapper.ts
index c60d5fe33..40a554522 100644
--- a/packages/web3-wrapper/src/web3_wrapper.ts
+++ b/packages/web3-wrapper/src/web3_wrapper.ts
@@ -19,6 +19,8 @@ import * as Web3 from 'web3';
 
 import { Web3WrapperErrors } from './types';
 
+const BASE_TEN = 10;
+
 /**
  * A wrapper around the Web3.js 0.x library that provides a consistent, clean promise-based interface.
  */
@@ -48,7 +50,7 @@ export class Web3Wrapper {
      * @return  The amount in units.
      */
     public static toUnitAmount(amount: BigNumber, decimals: number): BigNumber {
-        const aUnit = new BigNumber(10).pow(decimals);
+        const aUnit = new BigNumber(BASE_TEN).pow(decimals);
         const unit = amount.div(aUnit);
         return unit;
     }
@@ -61,7 +63,7 @@ export class Web3Wrapper {
      * @return  The amount in baseUnits.
      */
     public static toBaseUnitAmount(amount: BigNumber, decimals: number): BigNumber {
-        const unit = new BigNumber(10).pow(decimals);
+        const unit = new BigNumber(BASE_TEN).pow(decimals);
         const baseUnitAmount = amount.times(unit);
         const hasDecimals = baseUnitAmount.decimalPlaces() !== 0;
         if (hasDecimals) {
@@ -180,8 +182,8 @@ export class Web3Wrapper {
     public async doesContractExistAtAddressAsync(address: string): Promise<boolean> {
         const code = await promisify<string>(this._web3.eth.getCode)(address);
         // Regex matches 0x0, 0x00, 0x in order to accommodate poorly implemented clients
-        const codeIsEmpty = /^0x0{0,40}$/i.test(code);
-        return !codeIsEmpty;
+        const isCodeEmpty = /^0x0{0,40}$/i.test(code);
+        return !isCodeEmpty;
     }
     /**
      * Sign a message with a specific address's private key (`eth_sign`)
@@ -326,6 +328,10 @@ export class Web3Wrapper {
     }
     /**
      * Waits for a transaction to be mined and returns the transaction receipt.
+     * Note that just because a transaction was mined does not mean it was
+     * successful. You need to check the status code of the transaction receipt
+     * to find out if it was successful, or use the helper method
+     * awaitTransactionSuccessAsync.
      * @param   txHash            Transaction hash
      * @param   pollingIntervalMs How often (in ms) should we check if the transaction is mined.
      * @param   timeoutMs         How long (in ms) to poll for transaction mined until aborting.
@@ -336,16 +342,16 @@ export class Web3Wrapper {
         pollingIntervalMs: number = 1000,
         timeoutMs?: number,
     ): Promise<TransactionReceiptWithDecodedLogs> {
-        let timeoutExceeded = false;
+        let wasTimeoutExceeded = false;
         if (timeoutMs) {
-            setTimeout(() => (timeoutExceeded = true), timeoutMs);
+            setTimeout(() => (wasTimeoutExceeded = true), timeoutMs);
         }
 
         const txReceiptPromise = new Promise(
             (resolve: (receipt: TransactionReceiptWithDecodedLogs) => void, reject) => {
                 const intervalId = intervalUtils.setAsyncExcludingInterval(
                     async () => {
-                        if (timeoutExceeded) {
+                        if (wasTimeoutExceeded) {
                             intervalUtils.clearAsyncExcludingInterval(intervalId);
                             return reject(Web3WrapperErrors.TransactionMiningTimeout);
                         }
@@ -375,6 +381,28 @@ export class Web3Wrapper {
         const txReceipt = await txReceiptPromise;
         return txReceipt;
     }
+    /**
+     * Waits for a transaction to be mined and returns the transaction receipt.
+     * Unlike awaitTransactionMinedAsync, it will throw if the receipt has a
+     * status that is not equal to 1. A status of 0 or null indicates that the
+     * transaction was mined, but failed. See:
+     * https://github.com/ethereum/wiki/wiki/JavaScript-API#web3ethgettransactionreceipt
+     * @param   txHash            Transaction hash
+     * @param   pollingIntervalMs How often (in ms) should we check if the transaction is mined.
+     * @param   timeoutMs         How long (in ms) to poll for transaction mined until aborting.
+     * @return  Transaction receipt with decoded log args.
+     */
+    public async awaitTransactionSuccessAsync(
+        txHash: string,
+        pollingIntervalMs: number = 1000,
+        timeoutMs?: number,
+    ): Promise<TransactionReceiptWithDecodedLogs> {
+        const receipt = await this.awaitTransactionMinedAsync(txHash, pollingIntervalMs, timeoutMs);
+        if (receipt.status !== 1) {
+            throw new Error(`Transaction failed: ${txHash}`);
+        }
+        return receipt;
+    }
     private async _sendRawPayloadAsync<A>(payload: Partial<JSONRPCRequestPayload>): Promise<A> {
         const sendAsync = this._web3.currentProvider.sendAsync.bind(this._web3.currentProvider);
         const response = await promisify<JSONRPCResponsePayload>(sendAsync)(payload);