Use let/const instead of var

.eslintrc

@@ -5,6 +5,7 @@
     "no-console": 0,
     "no-mixed-requires": 0,
     "no-multiple-empty-lines": [2, {"max": 1}],
+    "no-var": "error",
     "global-require": 0
   },
   "env": {

examples/custom_master_and_ipc/master.js

@@ -1,5 +1,5 @@
 /** @type {ClusterProcess} Master or Worker instance */
-var proc = require('luster');
+const proc = require('luster');
 
 if (proc.isMaster) {
     // register command repeater in the master

examples/custom_master_and_ipc/worker.js

@@ -1,4 +1,4 @@
-var http = require('http'),
+const http = require('http'),
     worker = require('luster'),
     counters = {};
 

examples/simple_extension/worker.js

@@ -1,4 +1,4 @@
-var http = require('http'),
+const http = require('http'),
     cluster = require('cluster');
 
 if (cluster.worker.id === 1) {

examples/simple_server/worker.js

@@ -1,4 +1,4 @@
-var http = require('http'),
+const http = require('http'),
     worker = require('luster');
 
 if (worker.wid === 1 || worker.wid === 0) {

lib/cluster_process.js

@@ -1,12 +1,11 @@
-var cluster = require('cluster'),
+const cluster = require('cluster'),
     path = require('path'),
     RPC = require('./rpc'),
     RPCCallback = require('./rpc-callback'),
     Configuration = require('./configuration'),
     EventEmitterEx = require('./event_emitter_ex'),
     LusterClusterProcessError = require('./errors').LusterClusterProcessError,
-    LusterConfigurationError = require('./errors').LusterConfigurationError,
-    ClusterProcess;
+    LusterConfigurationError = require('./errors').LusterConfigurationError;
 
 /**
  * @param {Object} context
@@ -27,7 +26,7 @@ function has(context, propName) {
  * @class ClusterProcess
  * @augments EventEmitterEx
  */
-ClusterProcess = EventEmitterEx.create(function ClusterProcess() {
+const ClusterProcess = EventEmitterEx.create(function ClusterProcess() {
     ClusterProcess.__super.apply(this, arguments);
 
     /** @private */
@@ -116,10 +115,10 @@ ClusterProcess.prototype.configure = function(config, applyEnv, basedir) {
  * @param {Function} callback function(error)
  */
 ClusterProcess.prototype.loadExtension = function(name, callback) {
-    var /** @type Extension */
+    const /** @type Extension */
         extension = require(name),
-        self = this,
-        config = this.config.get('extensions.' + name);
+        self = this;
+    let config = this.config.get('extensions.' + name);
 
     this.extensions[name] = extension;
 
@@ -147,13 +146,12 @@ function extendResolvePath(basedir) {
     // using module internals isn't good, but restarting with corrected NODE_PATH looks more ugly, IMO
     module.paths.push(basedir);
 
-    var _basedir = basedir.split('/'),
-        size = basedir.length,
-        i = 0,
-        modulesPath;
+    const _basedir = basedir.split('/'),
+        size = basedir.length;
+    let i = 0;
 
     while (size > i++) {
-        modulesPath = _basedir.slice(0, i).join('/') + '/node_modules';
+        const modulesPath = _basedir.slice(0, i).join('/') + '/node_modules';
 
         if (module.paths.indexOf(modulesPath) === -1) {
             module.paths.push(modulesPath);
@@ -178,12 +176,12 @@ ClusterProcess.prototype._onConfigured = function() {
         this.config.resolve('extensionsPath', path.dirname(this.config.resolve('app')))
     ));
 
-    var self = this,
+    const self = this,
         extensions = this.config.getKeys('extensions'),
         wait = extensions.length,
         loadedExtensions = [],
-        loadTimeout = this.config.get('extensionsLoadTimeout', 10000),
-        loadTimer;
+        loadTimeout = this.config.get('extensionsLoadTimeout', 10000);
+    let loadTimer;
 
     if (wait === 0) {
         self._initialized = true;
@@ -209,7 +207,7 @@ ClusterProcess.prototype._onConfigured = function() {
     }, this);
 
     loadTimer = setTimeout(function() {
-        var timeouted = extensions.filter(function (name) {
+        const timeouted = extensions.filter(function (name) {
                 return loadedExtensions.indexOf(name) < 0;
             }),
             error = LusterClusterProcessError.createError(
@@ -295,7 +293,7 @@ ClusterProcess.prototype._setupIPCMessagesHandler = function() {
  * @private
  */
 ClusterProcess.prototype._onMessage = function(target, rawMessage) {
-    var message = RPC.parseMessage(rawMessage);
+    const message = RPC.parseMessage(rawMessage);
 
     if (message === null) {
         return;

lib/configuration/check.js

@@ -1,7 +1,6 @@
-var LusterConfigurationError = require('../errors').LusterConfigurationError,
+const LusterConfigurationError = require('../errors').LusterConfigurationError,
     typeOf = require('./helpers').typeOf,
-    get = require('./helpers').get,
-    CHECKS;
+    get = require('./helpers').get;
 
 /**
  * @typedef PropertyCheck
@@ -16,7 +15,7 @@ var LusterConfigurationError = require('../errors').LusterConfigurationError,
  * @type {Object}
  * @property {PropertyCheck} *
  */
-CHECKS = {
+const CHECKS = {
     // path to worker main module
     'app': { required: true, type: 'string' },
     // number of workers to spawn
@@ -51,8 +50,7 @@ CHECKS = {
  * @throws {LusterConfigurationError} if property check has been failed
  */
 function checkProperty(path, value, check) {
-    var type = typeOf(value),
-        allowedTypes;
+    const type = typeOf(value);
 
     // required property
     if (type === 'undefined') {
@@ -66,7 +64,7 @@ function checkProperty(path, value, check) {
     }
 
     // allowed types
-    allowedTypes = check.type && [].concat(check.type);
+    const allowedTypes = check.type && [].concat(check.type);
     if (allowedTypes && allowedTypes.indexOf(type) === -1) {
         throw LusterConfigurationError.createError(
             LusterConfigurationError.CODES.PROP_TYPE_CHECK_FAILED,
@@ -84,7 +82,7 @@ function checkProperty(path, value, check) {
  * @returns {Number} of failed checks
  */
 function checkConfiguration(conf) {
-    var failedChecks = 0;
+    let failedChecks = 0;
 
     Object
         .keys(CHECKS)

lib/configuration/helpers.js

@@ -1,12 +1,12 @@
-var util = require('util'),
+const util = require('util'),
     LusterConfigurationError = require('../errors').LusterConfigurationError;
 
 /**
  * @param {*} value
  * @returns {String} `typeof` result extended with 'array', 'regexp', 'date' and 'error'
  */
 function typeOf(value) {
-    var type = typeof value;
+    let type = typeof value;
 
     if (type === 'object') {
         if (util.isArray(value)) {
@@ -29,16 +29,15 @@ function typeOf(value) {
  * @param {*} value
  */
 function set(context, path, value) {
-    var ctx = context,
-        props = path.split('.'),
+    let ctx = context;
+
+    const props = path.split('.'),
         target = props.pop(),
-        i, size,
-        propName,
-        type;
+        size = props.length;
 
-    for (i = 0, size = props.length; i < size; i++) {
-        propName = props[i];
-        type = typeOf(ctx[propName]);
+    for (let i = 0; i < size; i++) {
+        const propName = props[i];
+        const type = typeOf(ctx[propName]);
 
         if (type === 'undefined') {
             ctx[propName] = {};
@@ -66,12 +65,12 @@ function get(context, path, defaultValue) {
         return context;
     }
 
-    var props = path.split('.'),
-        prop = props[0],
-        i, size,
-        ctx = context;
+    const props = path.split('.'),
+        size = props.length;
+
+    let ctx = context;
 
-    for (i = 0, size = props.length; i < size; prop = props[++i]) {
+    for (let i = 0, prop = props[0]; i < size; prop = props[++i]) {
         if (typeof ctx === 'undefined' || ctx === null ||
             ! Object.prototype.hasOwnProperty.call(ctx, prop)) {
             return defaultValue;
@@ -93,12 +92,12 @@ function has(context, path) {
         return context;
     }
 
-    var props = path.split('.'),
-        prop = props[0],
-        i, size,
-        ctx = context;
+    const props = path.split('.'),
+        size = props.length;
+
+    let ctx = context;
 
-    for (i = 0, size = props.length; i < size; prop = props[++i]) {
+    for (let i = 0, prop = props[0]; i < size; prop = props[++i]) {
         if (typeof ctx === 'undefined' || ctx === null ||
             ! Object.prototype.hasOwnProperty.call(ctx, prop)) {
             return false;

lib/configuration/index.js

@@ -1,4 +1,4 @@
-var path = require('path'),
+const path = require('path'),
     typeOf = require('./helpers').typeOf,
     get = require('./helpers').get,
     set = require('./helpers').set,
@@ -48,7 +48,7 @@ Configuration.prototype.has = function(path) {
  * @public
  */
 Configuration.prototype.getKeys = function(path) {
-    var obj = get(this, path);
+    const obj = get(this, path);
 
     if (typeOf(obj) !== 'object') {
         return [];
@@ -133,16 +133,14 @@ Configuration.applyEnvironment = function(config) {
     }
 
     function parseProp(prop) {
-        var delimeterPos = prop.indexOf('='),
-            propPath,
-            propValue;
+        const delimeterPos = prop.indexOf('=');
 
         if (delimeterPos === 0 || delimeterPos === -1) {
             return;
         }
 
-        propPath = prop.substr(0, delimeterPos).trim();
-        propValue = prop.substr(delimeterPos + 1).trim();
+        const propPath = prop.substr(0, delimeterPos).trim();
+        let propValue = prop.substr(delimeterPos + 1).trim();
 
         if (propValue === '') {
             propValue = undefined;
@@ -158,8 +156,9 @@ Configuration.applyEnvironment = function(config) {
         set(config, propPath, propValue);
     }
 
-    var conf = process.env.LUSTER_CONF,
-        lastSeparator = -1,
+    const conf = process.env.LUSTER_CONF;
+
+    let lastSeparator = -1,
         i = 0,
         openQuote = false;
 

lib/errors.js

@@ -1,12 +1,12 @@
-var Terror = require('terror'),
+const Terror = require('terror'),
     errors = {};
 
 /**
  * @constructor
  * @class LusterError
  * @augments Terror
  */
-var LusterError = errors.LusterError = Terror.create('LusterError',
+const LusterError = errors.LusterError = Terror.create('LusterError',
     {
         ABSTRACT_METHOD_IS_NOT_IMPLEMENTED:
             'Abstract method "%method%" is not implemented in the %klass%'

lib/event_emitter_ex.js

@@ -1,4 +1,4 @@
-var Objex = require('objex'),
+const Objex = require('objex'),
     util = require('util'),
     EventEmitter = require('events').EventEmitter,
 
@@ -17,7 +17,7 @@ function inspect(val) {
 // add 'luster:eex' to the `NODE_DEBUG` environment variable to enable events logging
 if (process.env.NODE_DEBUG && /luster:eex/i.test(process.env.NODE_DEBUG)) {
     EventEmitterEx.prototype.emit = function() {
-        var args = Array.prototype
+        const args = Array.prototype
             .slice.call(arguments, 0)
             .map(inspect);
 

lib/luster.js

@@ -1,4 +1,4 @@
-var cluster = require('cluster'),
+const cluster = require('cluster'),
     /** @type {ClusterProcess} */
     Proc = require(cluster.isMaster ? './master' : './worker');