ERC777 Make expectEvent compatible with web3.js 1.0 (OpenZeppelin#1159)

test/helpers/expectEvent.js

@@ -1,8 +1,21 @@
-const BigNumber = web3.BigNumber;
+const BigNumber = web3.utils.BN;
 const should = require('chai')
   .use(require('chai-bignumber')(BigNumber))
   .should();
 
+function inEvents (events, eventName, eventArgs = {}) {
+  event = Object.values(events).find(function (e) {
+    if (e.event === eventName) {
+      for (const [k, v] of Object.entries(eventArgs)) {
+        contains(e.returnValues, k, v);
+      }
+      return true;
+    }
+  });
+  should.exist(event);
+  return event;
+}
+
 function inLogs (logs, eventName, eventArgs = {}) {
   const event = logs.find(function (e) {
     if (e.event === eventName) {
@@ -22,8 +35,11 @@ async function inTransaction (tx, eventName, eventArgs = {}) {
 }
 
 function contains (args, key, value) {
-  if (isBigNumber(args[key])) {
-    args[key].should.be.bignumber.equal(value);
+  if (args[key] == null) {
+    value.should.be.equal("0x00");
+  }
+  else if (isBigNumber(args[key])) {
+    args[key].toString().should.be.equal(value);
   } else {
     args[key].should.be.equal(value);
   }
@@ -36,6 +52,7 @@ function isBigNumber (object) {
 }
 
 module.exports = {
+  inEvents,
   inLogs,
   inTransaction,
 };