Merge branch 'development' into feature/sra-reporter

* development: (71 commits)
  Set max to 2 ETH/2 ZRX
  Add missing types from website
  Add dependencies
  Update the README
  Move BaseContract to its own package
  Upgrate prettier
  remove unused import
  Move more configs into docsInfo and remove logic that does not belong there elsewhere
  Fix a bug with displaying solidity functions returning multiple return values
  Add ethers-contracts as a dependency
  Include types for ethers-contracts
  Fix the version
  Include types for ethers-contracts
  Rename idx to i
  Remove tslint disable
  Move BaseContract to web3Wrapper
  Merge ifs
  Fix an option description
  Add link to the docs
  Improve CHANGELOG entry
  ...

5 files changed, 26 insertions, 18 deletions

diff --git a/packages/utils/CHANGELOG.md b/packages/utils/CHANGELOG.md
index 19ee80e4f..81792bee8 100644
--- a/packages/utils/CHANGELOG.md
+++ b/packages/utils/CHANGELOG.md
@@ -1,5 +1,9 @@
 # CHANGELOG
 
+## v0.4.0 - _TBD, 2018_
+
+    * Use `ethers-contracts` as a backend to decode event args (#413)
+
 ## v0.3.2 - _February 9, 2018_
 
     * Fix publishing issue where .npmignore was not properly excluding undesired content (#389)
diff --git a/packages/utils/package.json b/packages/utils/package.json
index 750ecaa2f..4f63aa4ce 100644
--- a/packages/utils/package.json
+++ b/packages/utils/package.json
@@ -21,16 +21,18 @@
     "homepage": "https://github.com/0xProject/0x.js/packages/utils/README.md",
     "devDependencies": {
         "@0xproject/tslint-config": "^0.4.9",
-        "@0xproject/types": "^0.2.3",
         "@types/lodash": "^4.14.86",
         "npm-run-all": "^4.1.2",
         "shx": "^0.2.2",
         "tslint": "5.8.0",
         "typescript": "2.7.1",
+        "ethers-typescript-typings": "^0.0.1",
         "web3-typescript-typings": "^0.9.11"
     },
     "dependencies": {
+        "@0xproject/types": "^0.2.3",
         "bignumber.js": "~4.1.0",
+        "ethers-contracts": "^2.2.1",
         "js-sha3": "^0.7.0",
         "lodash": "^4.17.4",
         "web3": "^0.20.0"
diff --git a/packages/utils/src/abi_decoder.ts b/packages/utils/src/abi_decoder.ts
index 368973b1b..2b496eb17 100644
--- a/packages/utils/src/abi_decoder.ts
+++ b/packages/utils/src/abi_decoder.ts
@@ -1,7 +1,7 @@
 import { AbiType, DecodedLogArgs, LogWithDecodedArgs, RawLog, SolidityTypes } from '@0xproject/types';
+import * as ethersContracts from 'ethers-contracts';
 import * as _ from 'lodash';
 import * as Web3 from 'web3';
-import * as SolidityCoder from 'web3/lib/solidity/coder';
 
 import { BigNumber } from './configured_bignumber';
 
@@ -27,31 +27,29 @@ export class AbiDecoder {
         if (_.isUndefined(event)) {
             return log;
         }
+        const ethersInterface = new ethersContracts.Interface([event]);
         const logData = log.data;
         const decodedParams: DecodedLogArgs = {};
-        let dataIndex = 0;
         let topicsIndex = 1;
 
         const nonIndexedInputs = _.filter(event.inputs, input => !input.indexed);
         const dataTypes = _.map(nonIndexedInputs, input => input.type);
-        const decodedData = SolidityCoder.decodeParams(dataTypes, logData.slice('0x'.length));
+        const decodedData = ethersInterface.events[event.name].parse(log.data);
 
         let failedToDecode = false;
-        _.forEach(event.inputs, (param: Web3.EventParameter) => {
+        _.forEach(event.inputs, (param: Web3.EventParameter, i: number) => {
             // Indexed parameters are stored in topics. Non-indexed ones in decodedData
-            let value: BigNumber | string = param.indexed ? log.topics[topicsIndex++] : decodedData[dataIndex++];
+            let value: BigNumber | string | number = param.indexed ? log.topics[topicsIndex++] : decodedData[i];
             if (_.isUndefined(value)) {
                 failedToDecode = true;
                 return;
             }
             if (param.type === SolidityTypes.Address) {
                 value = AbiDecoder._padZeros(new BigNumber(value).toString(16));
-            } else if (
-                param.type === SolidityTypes.Uint256 ||
-                param.type === SolidityTypes.Uint8 ||
-                param.type === SolidityTypes.Uint
-            ) {
+            } else if (param.type === SolidityTypes.Uint256 || param.type === SolidityTypes.Uint) {
                 value = new BigNumber(value);
+            } else if (param.type === SolidityTypes.Uint8) {
+                value = new BigNumber(value).toNumber();
             }
             decodedParams[param.name] = value;
         });
@@ -67,11 +65,14 @@ export class AbiDecoder {
         }
     }
     private _addABI(abiArray: Web3.AbiDefinition[]): void {
+        if (_.isUndefined(abiArray)) {
+            return;
+        }
+        const ethersInterface = new ethersContracts.Interface(abiArray);
         _.map(abiArray, (abi: Web3.AbiDefinition) => {
             if (abi.type === AbiType.Event) {
-                const signature = `${abi.name}(${_.map(abi.inputs, input => input.type).join(',')})`;
-                const signatureHash = new Web3().sha3(signature);
-                this._methodIds[signatureHash] = abi;
+                const topic = ethersInterface.events[abi.name].topic;
+                this._methodIds[topic] = abi;
             }
         });
         this._savedABIs = this._savedABIs.concat(abiArray);
diff --git a/packages/utils/src/globals.d.ts b/packages/utils/src/globals.d.ts
deleted file mode 100644
index ade9e59db..000000000
--- a/packages/utils/src/globals.d.ts
+++ /dev/null
@@ -1,3 +0,0 @@
-declare module 'web3/lib/solidity/coder' {
-    const decodeParams: (types: string[], data: string) => any[];
-}
diff --git a/packages/utils/tsconfig.json b/packages/utils/tsconfig.json
index 3d967d05f..8114d99cd 100644
--- a/packages/utils/tsconfig.json
+++ b/packages/utils/tsconfig.json
@@ -3,5 +3,9 @@
     "compilerOptions": {
         "outDir": "lib"
     },
-    "include": ["./src/**/*", "../../node_modules/web3-typescript-typings/index.d.ts"]
+    "include": [
+        "./src/**/*",
+        "../../node_modules/web3-typescript-typings/index.d.ts",
+        "../../node_modules/ethers-typescript-typings/index.d.ts"
+    ]
 }