Merge branch 'development' into feature/sra-reporter

* development: (68 commits)
  Update list of packages and organize them alphabetically
  Fix prettier issues
  Add support for going back to previous hashes via the browser back button to wiki
  Scroll to previous hashed elements when user clicks back button
  Add back strict null checks to react-shared package and fix issues
  remove ability to have implicit dependencies and add missing deps
  update license
  remove no-implicit-this
  Add example & screenshot to npmignore
  Remove `;` to be nice to windows users
  Use unencoded @ symbol, browser will fix
  Fix external type links
  Add comment about commented out CSS exception
  Update prettier since the previous version had a bug when dealing with css files
  Fix css files with prettier
  Added base-contract package to README
  Prettify test jsons
  Update yarn.lock
  Improve README
  Feedback
  ...

2 files changed, 15 insertions, 2 deletions

diff --git a/packages/deployer/CHANGELOG.md b/packages/deployer/CHANGELOG.md
index 05383bed5..ccfdd6a3b 100644
--- a/packages/deployer/CHANGELOG.md
+++ b/packages/deployer/CHANGELOG.md
@@ -2,7 +2,8 @@
 
 ## v0.2.0 - _March 4, 2018_
 
-    * Check dependencies when determining if contracts should be recompiled (#408).
+    * Check dependencies when determining if contracts should be recompiled (#408)
+    * Improve an error message for when deployer is supplied with an incorrect number of constructor arguments (#419)
 
 ## v0.1.0 - _February 16, 2018_
 
diff --git a/packages/deployer/src/deployer.ts b/packages/deployer/src/deployer.ts
index 6710bcc85..e87d2ab0e 100644
--- a/packages/deployer/src/deployer.ts
+++ b/packages/deployer/src/deployer.ts
@@ -1,4 +1,4 @@
-import { TxData } from '@0xproject/types';
+import { AbiType, TxData } from '@0xproject/types';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import * as _ from 'lodash';
 import * as Web3 from 'web3';
@@ -49,6 +49,18 @@ export class Deployer {
             gas,
         };
         const abi = contractNetworkDataIfExists.abi;
+        const constructorAbi = _.find(abi, { type: AbiType.Constructor }) as Web3.ConstructorAbi;
+        const constructorArgs = _.isUndefined(constructorAbi) ? [] : constructorAbi.inputs;
+        if (constructorArgs.length !== args.length) {
+            const constructorSignature = `constructor(${_.map(constructorArgs, arg => `${arg.type} ${arg.name}`).join(
+                ', ',
+            )})`;
+            throw new Error(
+                `${contractName} expects ${constructorArgs.length} constructor params: ${constructorSignature}. Got ${
+                    args.length
+                }`,
+            );
+        }
         const web3ContractInstance = await this._deployFromAbiAsync(abi, args, txData);
         utils.consoleLog(`${contractName}.sol successfully deployed at ${web3ContractInstance.address}`);
         const contractInstance = new Contract(web3ContractInstance, this._defaults);