Switch from JSHint to ESLint

This switches us from JSHint to ESLint, improving the quality and
consistency of our code. (We also use ESLint elsewhere at Airtable.)

To break down this change:

* We made several cleanups before this commit to ease the transition.
  See [#95][1], [#96][2], [#97][3], [#98][4], [#99][5], [#101][6] (and a
  fix in [#107][7]), [#105][8], [#109][9], [#118][10], [#119][11],
  [#120][12]
* Installed `eslint`
* Add `.eslintrc.json` and `.eslintignore` (and a slightly-different
  `.eslintrc.json` in `test`)
* Remove JSHint. Involved uninstalling the package, removing it from the
  gruntfile, and removing `jshint ignore`s.
* Update the `lint` task in `package.json`
* Update `return` into `return void 0` for consistent returns in
  `callbackToPromise`
* Add one `// eslint-disable-line` comment in a single test file
* Run `eslint --fix .`, automatically fixing all of the remaining
  warnings and errors

[1]: #95
[2]: #96
[3]: #97
[4]: #98
[5]: #99
[6]: #101
[7]: #107
[8]: #105
[9]: #109
[10]: #118
[11]: #119
[12]: #120

.eslintignore

@@ -0,0 +1,3 @@
+/node_modules/
+/build/airtable.browser.js
+/test/test_files/airtable.browser.js

.eslintrc.json

@@ -0,0 +1,115 @@
+{
+    "env": {
+        "browser": true,
+        "node": true
+    },
+    "globals": {
+        "Promise": true
+    },
+    "extends": [
+        "eslint:recommended"
+    ],
+    "rules": {
+        "no-case-declarations": "warn",
+        "no-debugger": "warn",
+        "no-empty": "warn",
+        "no-extra-boolean-cast": "warn",
+        "no-extra-semi": "warn",
+        "no-redeclare": "warn",
+        "no-regex-spaces": "warn",
+        "no-self-assign": "warn",
+        "no-sparse-arrays": "warn",
+        "no-unreachable": "warn",
+        "no-console": "off",
+        "require-yield": "off",
+        "array-bracket-spacing": "warn",
+        "array-callback-return": "error",
+        "arrow-spacing": "warn",
+        "block-scoped-var": "error",
+        "block-spacing": "warn",
+        "comma-spacing": "warn",
+        "comma-style": "warn",
+        "computed-property-spacing": "warn",
+        "consistent-return": "error",
+        "consistent-this": ["warn", "that"],
+        "curly": "warn",
+        "default-case": "warn",
+        "dot-notation": ["warn", {"allowPattern": "[$_0-9]"}],
+        "eqeqeq": "error",
+        "func-call-spacing": "error",
+        "guard-for-in": "error",
+        "handle-callback-err": "error",
+        "key-spacing": "warn",
+        "keyword-spacing": "warn",
+        "linebreak-style": "warn",
+        "indent": ["warn", 4],
+        "new-parens": "warn",
+        "no-array-constructor": "error",
+        "no-caller": "error",
+        "no-catch-shadow": "error",
+        "no-confusing-arrow": "warn",
+        "no-constant-condition": "warn",
+        "no-div-regex": "warn",
+        "no-eq-null": "error",
+        "no-eval": "error",
+        "no-extend-native": "error",
+        "no-extra-bind": "warn",
+        "no-extra-label": "error",
+        "no-floating-decimal": "warn",
+        "no-global-assign": "warn",
+        "no-implicit-globals": "warn",
+        "no-implied-eval": "error",
+        "no-iterator": "error",
+        "no-labels": "error",
+        "no-label-var": "error",
+        "no-loop-func": "error",
+        "no-lone-blocks": "error",
+        "no-native-reassign": "error",
+        "no-mixed-operators": ["warn", {"groups": [["&&", "||"]]}],
+        "no-mixed-requires": "error",
+        "no-multi-spaces": "warn",
+        "no-multi-str": "warn",
+        "no-new-object": "warn",
+        "no-new-require": "error",
+        "no-new-wrappers": "warn",
+        "no-octal-escape": "error",
+        "no-path-concat": "error",
+        "no-proto": "error",
+        "no-script-url": "error",
+        "no-sequences": "error",
+        "no-self-compare": "error",
+        "no-shadow": "error",
+        "no-shadow-restricted-names": "error",
+        "no-spaced-func": "warn",
+        "no-template-curly-in-string": "error",
+        "no-throw-literal": "warn",
+        "no-undef": "error",
+        "no-undef-init": "warn",
+        "no-unneeded-ternary": "warn",
+        "no-unsafe-negation": "warn",
+        "no-unused-expressions": "error",
+        "no-unused-vars": "warn",
+        "no-useless-call": "warn",
+        "no-useless-computed-key": "warn",
+        "no-useless-concat": "warn",
+        "no-useless-constructor": "warn",
+        "no-undefined": "error",
+        "no-whitespace-before-property": "warn",
+        "no-with": "error",
+        "object-curly-spacing": "warn",
+        "one-var-declaration-per-line": "warn",
+        "quotes": ["warn", "single", "avoid-escape"],
+        "radix": "error",
+        "semi": "warn",
+        "semi-spacing": "warn",
+        "space-before-blocks": "warn",
+        "space-before-function-paren": [
+            "warn",
+            {"anonymous": "never", "named": "never", "asyncArrow": "always"}
+        ],
+        "space-in-parens": "warn",
+        "space-unary-ops": "warn",
+        "spaced-comment": "warn",
+        "yoda": "warn"
+    }
+}

gruntfile.js

@@ -6,32 +6,6 @@ module.exports = function(grunt) {
     // Project configuration.
     grunt.initConfig({
         pkg: pkg,
-        jshint: {
-            // define the files to lint
-            files: ['gruntfile.js', 'lib/**/!(class.js)*.js', 'test/*.test.js'],
-            // configure JSHint (documented at http://www.jshint.com/docs/)
-            options: {
-                // more options here if you want to override JSHint defaults
-                strict: true,
-                globalstrict: true,
-                globals: {
-                    console: true,
-                    module: true,
-                    require: true,
-                    process: true,
-                    setTimeout: true,
-                    jest: true,
-                    describe: true,
-                    beforeEach: true,
-                    beforeAll: true,
-                    afterAll: true,
-                    it: true,
-                    expect: true,
-                    Promise: true,
-                    __dirname: true
-                }
-            }
-        },
         browserify: {
             client: {
                 src: './lib/airtable.js',
@@ -44,18 +18,12 @@ module.exports = function(grunt) {
                         }]
                     ],
                     preBundleCB: function(b) {
-                        b.require('./lib/airtable.js', { expose: 'airtable' });
+                        b.require('./lib/airtable.js', {expose: 'airtable'});
                     }
                 }
             }
         },
     });
 
-    // Load the plugin that provides the "uglify" task.
-    grunt.loadNpmTasks('grunt-contrib-jshint');
-
-    // Default task(s).
-    grunt.registerTask('default', ['jshint']);
-
     grunt.loadNpmTasks('grunt-browserify');
 };

lib/airtable.js

@@ -47,7 +47,7 @@ var Airtable = Class.extend({
     }
 });
 
-Airtable.default_config = function () {
+Airtable.default_config = function() {
     return {
         endpointUrl: process.env.AIRTABLE_ENDPOINT_URL || 'https://api.airtable.com',
         apiVersion: '0.1.0',

lib/airtable_error.js

@@ -12,7 +12,7 @@ var AirtableError = Class.extend({
         return [
             this.message,
             '(', this.error, ')',
-            this.statusCode ?  '[Http code ' + this.statusCode + ']' : ''
+            this.statusCode ? '[Http code ' + this.statusCode + ']' : ''
         ].join('');
     }
 });

lib/base.js

@@ -27,26 +27,26 @@ var Base = Class.extend({
         } else if (statusCode === 403) {
             return new AirtableError('NOT_AUTHORIZED', 'You are not authorized to perform this operation', statusCode);
         } else if (statusCode === 404) {
-            return (function(){
+            return (function() {
                 var message = (body && body.error && body.error.message) ? body.error.message : 'Could not find what you are looking for';
                 return new AirtableError('NOT_FOUND', message, statusCode);
             })();
         } else if (statusCode === 413) {
             return new AirtableError('REQUEST_TOO_LARGE', 'Request body is too large', statusCode);
         } else if (statusCode === 422) {
-            return (function(){
+            return (function() {
                 var type = (body && body.error && body.error.type) ? body.error.type : 'UNPROCESSABLE_ENTITY';
                 var message = (body && body.error && body.error.message) ? body.error.message : 'The operation cannot be processed';
                 return new AirtableError(type, message, statusCode);
             })();
         } else if (statusCode === 429) {
             return new AirtableError('TOO_MANY_REQUESTS', 'You have made too many requests in a short period of time. Please retry your request later', statusCode);
-        }else if (statusCode === 500) {
+        } else if (statusCode === 500) {
             return new AirtableError('SERVER_ERROR', 'Try again. If the problem persists, contact support.', statusCode);
         } else if (statusCode === 503) {
             return new AirtableError('SERVICE_UNAVAILABLE', 'The service is temporarily unavailable. Please retry shortly.', statusCode);
         } else if (statusCode >= 400) {
-            return (function(){
+            return (function() {
                 var type = (body && body.error && body.error.type) ? body.error.type : 'UNEXPECTED_ERROR';
                 var message = (body && body.error && body.error.message) ? body.error.message : 'An unexpected error occurred';
                 return new AirtableError(type, message, statusCode);

lib/callback_to_promise.js

@@ -17,7 +17,7 @@ function callbackToPromise(fn, context, callbackArgIndex) {
         var callbackArg = arguments[thisCallbackArgIndex];
         if (typeof callbackArg === 'function') {
             fn.apply(context, arguments);
-            return;
+            return void 0;
         } else {
             var args = [];
             // If an explicit callbackArgIndex is set, but the function is called

lib/class.js

@@ -1,4 +1,4 @@
-// jshint ignore: start
+/* eslint-disable */
 
 /* Simple JavaScript Inheritance
  * By John Resig http://ejohn.org/

lib/table.js

@@ -75,7 +75,7 @@ var Table = Class.extend({
             throw new Error('Airtable: the parameter for `select` should be a plain object or undefined.');
         }
     },
-    _urlEncodedNameOrId: function(){
+    _urlEncodedNameOrId: function() {
         return this.id || encodeURIComponent(this.name);
     },
     _createRecords: function(recordsData, optionalParameters, done) {
@@ -98,7 +98,7 @@ var Table = Class.extend({
 
             var result;
             if (isCreatingMultipleRecords) {
-                result = body.records.map(function (record) {
+                result = body.records.map(function(record) {
                     return new Record(that, record.id, record);
                 });
             } else {
@@ -121,7 +121,7 @@ var Table = Class.extend({
             this._base.runAction(method, '/' + this._urlEncodedNameOrId() + '/', {}, requestData, function(err, resp, body) {
                 if (err) { done(err); return; }
 
-                var result = body.records.map(function (record) {
+                var result = body.records.map(function(record) {
                     return new Record(that, record.id, record);
                 });
                 done(null, result);
@@ -144,7 +144,7 @@ var Table = Class.extend({
         if (isArray(recordIdsOrId)) {
             var that = this;
             var queryParams = {records: recordIdsOrId};
-            this._base.runAction('delete', '/' + this._urlEncodedNameOrId(), queryParams, null, function (err, response, results) {
+            this._base.runAction('delete', '/' + this._urlEncodedNameOrId(), queryParams, null, function(err, response, results) {
                 if (err) {
                     done(err);
                     return;
@@ -171,7 +171,7 @@ var Table = Class.extend({
             limit: limit, offset: offset
         }, opts);
 
-        this._base.runAction('get', '/' + this._urlEncodedNameOrId() + '/', listRecordsParameters, null, function (err, response, results) {
+        this._base.runAction('get', '/' + this._urlEncodedNameOrId() + '/', listRecordsParameters, null, function(err, response, results) {
             if (err) {
                 done(err);
                 return;