make ethersim optional

bin/embark

@@ -6,7 +6,6 @@ var wrench = require('wrench');
 var grunt = require('grunt');
 require('shelljs/global');
 var readYaml = require('read-yaml');
-var EtherSim = require('ethersim');
 var Embark = require('..');
 
 var run = function(cmd) {
@@ -175,6 +174,13 @@ program.command('meteor_demo').description('create a working meteor dapp with a
 });
 
 program.command('simulator').description('run a fast ethereum rpc simulator').action(function() {
+  try {
+    var EtherSim = require('ethersim');
+  } catch(e) {
+    console.log('EtherSim not found; Please install it with "npm install ethersim --save"');
+    console.log('For more information see https://github.com/iurimatias/ethersim');
+    exit();
+  }
   EtherSim.startServer();
 });
 

lib/test.js

@@ -1,7 +1,17 @@
-var ethersim = require('ethersim');
+try {
+  var ethersim = require('ethersim');
+} catch(e) {
+  var ethersim = false;
+}
 var web3 = require('web3');
 
 Test = function(contractFiles, blockchainFile, contractFile, _env) {
+  if (ethersim === false) {
+    console.log('EtherSim not found; Please install it with "npm install ethersim --save"');
+    console.log('For more information see https://github.com/iurimatias/ethersim');
+    exit();
+  }
+
   this.env = _env || 'development';
   this.web3 = web3;
   this.web3.setProvider(ethersim.web3Provider());

package.json

@@ -24,8 +24,7 @@
     "toposort": "^0.2.10",
     "web3": "^0.15.0",
     "bignumber.js": "debris/bignumber.js#master",
-    "wrench": "^1.5.8",
+    "wrench": "^1.5.8"
-    "ethersim": "^0.3.0"
   },
   "author": "Iuri Matias <iuri.matias@gmail.com>",
   "contributors": [],