Use eslint for javascript linting (#55)

Switch from jshint to eslint as linting dependency. Add basic config
with recommended rules and a few extra syntax enforcements.

Use eslint-plugin-mocha for some test specialisation.

Remove gulp lint task.

Remove old demo.min.js file.

Add eslint override comments as needed for now and fix a few issues.

Author: bz2

.eslintrc.json

@@ -0,0 +1,45 @@
+{
+  "env": {
+    "browser": true
+  },
+  "extends": [
+    "eslint:recommended"
+  ],
+  "parserOptions": {
+    "ecmaVersion": 5
+  },
+  "globals" : {
+    "Promise": false
+  },
+  "rules": {
+    "block-scoped-var": "error",
+    "complexity": ["error", 15],
+    "curly": "error",
+    "eqeqeq": ["error", "smart"],
+    "linebreak-style": ["error", "unix"],
+    "quote-props": ["error", "as-needed"],
+    "quotes": ["error", "single"],
+    "semi": "error",
+    "unicode-bom": ["error", "never"]
+  },
+  "overrides": [{
+    "files": ["test/*.js"],
+    "env": {
+      "mocha": true
+    },
+    "globals": {
+      "chai": false,
+      "sinon": false,
+      "StackdriverErrorReporter": false
+    },
+    "plugins": [
+      "mocha"
+    ],
+    "rules": {
+      "mocha/handle-done-callback": "error",
+      "mocha/no-exclusive-tests": "warn",
+      "mocha/no-nested-tests": "error",
+      "mocha/no-return-and-callback": "error"
+    }
+  }]
+}

demo/demo-angular.js

@@ -1,4 +1,4 @@
-angular.module('demoApp', [])
+angular.module('demoApp', []) // eslint-disable-line no-undef
 
   .factory('$exceptionHandler', ['$log', '$window', function($log, $window) {
     var StackdriverErrors = new $window.StackdriverErrorReporter();
@@ -18,4 +18,4 @@ angular.module('demoApp', [])
     demo.starUser = function() {
       demo.user.star();
     };
-  });
+  });

demo/demo.js

@@ -13,6 +13,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+// eslint-disable-next-line no-undef
 var StackdriverErrors = new StackdriverErrorReporter();
 
 function updateConfig() {
@@ -39,6 +40,7 @@ function loadFromLocalStorage() {
   if(key && projectId) {
     updateConfig();
   } else {
+    // eslint-disable-next-line no-console
     console.warn('No API key provided, Stackdriver not started.');
   }
 }
@@ -47,7 +49,7 @@ loadFromLocalStorage();
 
 // Fake application code
 var users;
-function vanillaCrash() {
+function vanillaCrash() { // eslint-disable-line no-unused-vars
   starUsers();
 }
 function starUsers() {
@@ -61,16 +63,16 @@ function displayUserInfo() {
   }
 }
 function addUser(name) {
-  var user = new User();
+  var user = new User(name); // eslint-disable-line no-undef
   users.push(user);
 }
 
 
 // Buttons logic
-function reportErrorMessage() {
+function reportErrorMessage() { // eslint-disable-line no-unused-vars
   displayUserInfo();
 }
-function catchCrashAndReport() {
+function catchCrashAndReport() { // eslint-disable-line no-unused-vars
   try {
     addUser('Keyser Söze');
   } catch (e) {

demo/demo.min.js

@@ -13,13 +13,13 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+/* global require */
 var gulp = require('gulp');
 var rename = require('gulp-rename');
 var replace = require('gulp-replace');
 var uglify = require('gulp-uglify');
 var sourcemaps = require('gulp-sourcemaps');
 var mochaPhantomJS = require('gulp-mocha-phantomjs');
-var jshint = require('gulp-jshint');
 var concat = require('gulp-concat');
 
 var SRC_FILE = 'stackdriver-errors.js';
@@ -29,12 +29,6 @@ var dependencies = [
     './node_modules/stacktrace-js/dist/stacktrace-with-promises-and-json-polyfills.js',
 ];
 
-gulp.task('lint', function() {
-  return gulp.src(SRC_FILE)
-    .pipe(jshint())
-    .pipe(jshint.reporter('default'));
-});
-
 gulp.task('test', function () {
     return gulp
     .src('test/test.html')
@@ -71,5 +65,5 @@ gulp.task('demo-js', function() {
     .pipe(gulp.dest('dist'));
 });
 
-gulp.task('default', ['lint', 'test']);
+gulp.task('default', ['test']);
 gulp.task('demo', ['dist', 'demo-html', 'demo-js']);