es6 updates

test/acceptance/babel-test.js

@@ -14,7 +14,7 @@ describe('acceptance - babel', function() {
       '--eslint-args="**/*.js"',
       '--mocha-args="--compilers js:babel-register test/**/*-test.js"'
     ];
-    return run(args, workingDir).then(function(stdout) {
+    return run(args, workingDir).then(stdout => {
       expect(stdout).to.contain(`${ok} this is my test`);
       expect(stdout).to.contain('my-file.js passes');
       expect(stdout).to.contain('my-test.js passes');
@@ -27,7 +27,7 @@ describe('acceptance - babel', function() {
       '--eslint-args="**/*.js"',
       '--mocha-args="--compilers js:babel-register,coffee:coffee-script test/**/*-test.js"'
     ];
-    return run(args, workingDir).catch(function(stderr) {
+    return run(args, workingDir).catch(stderr => {
       expect(stderr).to.contain('Error: Cannot find module \'coffee-script\'');
     });
   });

test/acceptance/failure-test.js

@@ -15,7 +15,7 @@ describe('acceptance - failure', function() {
       '--eslint-args="**/*.js"',
       '--mocha-args="test/**/*-test.js"'
     ];
-    return run(args, workingDir).then(function(stdout) {
+    return run(args, workingDir).then(stdout => {
       expect(stdout).to.contain(`${ok} this is my test`);
       expect(stdout).to.contain('my-file.js passes');
       expect(stdout).to.contain('my-test.js passes');