test: show diff when test:bin fails

package.json

@@ -35,6 +35,7 @@
     "babel-runtime": "^5.1.10",
     "benchmark": "~1.0",
     "chai": "^4.2.0",
+    "chai-diff": "^1.0.1",
     "concurrently": "^5.0.0",
     "dirty-chai": "^2.0.1",
     "dtslint": "^0.5.5",
@@ -84,7 +85,7 @@
   "scripts": {
     "format": "prettier --write '**/*.js' && eslint --fix .",
     "check-format": "prettier --check '**/*.js'",
-    "lint": "eslint --max-warnings 0 . ",
+    "lint": "eslint --max-warnings 0 .",
     "dtslint": "dtslint types",
     "test": "grunt",
     "extensive-tests-and-publish-to-aws": "npx mocha tasks/task-tests/ && grunt --stack extensive-tests-and-publish-to-aws",

tasks/test-bin.js

@@ -1,7 +1,10 @@
-const childProcess = require('child_process'),
-  fs = require('fs'),
-  os = require('os'),
-  expect = require('chai').expect;
+const childProcess = require('child_process');
+const fs = require('fs');
+const os = require('os');
+
+const chai = require('chai');
+chai.use(require('chai-diff'));
+const expect = chai.expect;
 
 module.exports = function(grunt) {
   grunt.registerTask('test:bin', function() {
@@ -18,7 +21,7 @@ module.exports = function(grunt) {
     const normalizedOutput = normalizeCrlf(stdout);
     const normalizedExpectedOutput = normalizeCrlf(expectedOutput);
 
-    expect(normalizedOutput).to.equal(normalizedExpectedOutput);
+    expect(normalizedOutput).not.to.be.differentFrom(normalizedExpectedOutput);
   });
 };