Enable prefer-const lint rule (#3202)

Author: Arthur Cinader

.eslintrc.json

@@ -19,6 +19,7 @@
         "no-trailing-spaces": 2,
         "eol-last": 2,
         "space-in-parens": ["error", "never"],
-        "no-multiple-empty-lines": 1
+        "no-multiple-empty-lines": 1,
+        "prefer-const": "error"
     }
 }

spec/Analytics.spec.js

@@ -17,7 +17,7 @@ describe('AnalyticsController', () => {
     }).then(() => {
       expect(analyticsAdapter.trackEvent).toHaveBeenCalled();
       var lastCall = analyticsAdapter.trackEvent.calls.first();
-      let args = lastCall.args;
+      const args = lastCall.args;
       expect(args[0]).toEqual('MyEvent');
       expect(args[1]).toEqual({
         dimensions: {
@@ -45,7 +45,7 @@ describe('AnalyticsController', () => {
     }).then(() => {
       expect(analyticsAdapter.appOpened).toHaveBeenCalled();
       var lastCall = analyticsAdapter.appOpened.calls.first();
-      let args = lastCall.args;
+      const args = lastCall.args;
       expect(args[0]).toEqual({
         dimensions: {
           key: 'value',

spec/AuthenticationAdapters.spec.js

@@ -208,7 +208,7 @@ describe('AuthenticationProviers', function() {
       id: 'hello',
       token: 'world'
     }
-    let adapter = {
+    const adapter = {
       validateAppId: function() {
         return Promise.resolve();
       },
@@ -220,15 +220,15 @@ describe('AuthenticationProviers', function() {
       }
     };
 
-    let authDataSpy = spyOn(adapter, 'validateAuthData').and.callThrough();
-    let appIdSpy = spyOn(adapter, 'validateAppId').and.callThrough();
+    const authDataSpy = spyOn(adapter, 'validateAuthData').and.callThrough();
+    const appIdSpy = spyOn(adapter, 'validateAppId').and.callThrough();
 
-    let authenticationHandler = authenticationLoader({
+    const authenticationHandler = authenticationLoader({
       customAuthentication: adapter
     });
 
     validateAuthenticationHandler(authenticationHandler);
-    let validator = authenticationHandler.getValidatorForProvider('customAuthentication');
+    const validator = authenticationHandler.getValidatorForProvider('customAuthentication');
     validateValidator(validator);
 
     validator(validAuthData).then(() => {
@@ -243,12 +243,12 @@ describe('AuthenticationProviers', function() {
   });
 
   it('properly loads custom adapter module object', (done) => {
-    let authenticationHandler = authenticationLoader({
+    const authenticationHandler = authenticationLoader({
       customAuthentication: path.resolve('./spec/support/CustomAuth.js')
     });
 
     validateAuthenticationHandler(authenticationHandler);
-    let validator = authenticationHandler.getValidatorForProvider('customAuthentication');
+    const validator = authenticationHandler.getValidatorForProvider('customAuthentication');
     validateValidator(validator);
 
     validator({
@@ -262,12 +262,12 @@ describe('AuthenticationProviers', function() {
   });
 
   it('properly loads custom adapter module object', (done) => {
-    let authenticationHandler = authenticationLoader({
+    const authenticationHandler = authenticationLoader({
       customAuthentication: { module: path.resolve('./spec/support/CustomAuthFunction.js'), options: { token: 'valid-token' }}
     });
 
     validateAuthenticationHandler(authenticationHandler);
-    let validator = authenticationHandler.getValidatorForProvider('customAuthentication');
+    const validator = authenticationHandler.getValidatorForProvider('customAuthentication');
     validateValidator(validator);
 
     validator({

spec/CLI.spec.js

@@ -94,7 +94,7 @@ describe('commander additions', () => {
       'PROGRAM_ARG_0': 'arg0ENVValue',
       'PROGRAM_ARG_1': 'arg1ENVValue',
     });
-    let options = commander.getOptions();
+    const options = commander.getOptions();
     expect(options.arg2).toBe(8888);
     expect(options.arg3).toBe('hello'); //config value
     expect(options.arg4).toBe('/1');
@@ -123,7 +123,7 @@ describe('commander additions', () => {
   it('should load config from apps', (done) => {
     commander.loadDefinitions(testDefinitions);
     commander.parse(['node', './CLI.spec.js', './spec/configs/CLIConfigApps.json']);
-    let options = commander.getOptions();
+    const options = commander.getOptions();
     expect(options.arg1).toBe('my_app');
     expect(options.arg2).toBe(8888);
     expect(options.arg3).toBe('hello'); //config value
@@ -142,8 +142,8 @@ describe('commander additions', () => {
 
 describe('definitions', () => {
   it('should have valid types', () => {
-    for (let key in definitions) {
-      let definition = definitions[key];
+    for (const key in definitions) {
+      const definition = definitions[key];
       expect(typeof definition).toBe('object');
       if (typeof definition.env !== 'undefined') {
         expect(typeof definition.env).toBe('string');
@@ -161,8 +161,8 @@ describe('definitions', () => {
 
 describe('LiveQuery definitions', () => {
   it('should have valid types', () => {
-    for (let key in liveQueryDefinitions) {
-      let definition = liveQueryDefinitions[key];
+    for (const key in liveQueryDefinitions) {
+      const definition = liveQueryDefinitions[key];
       expect(typeof definition).toBe('object');
       if (typeof definition.env !== 'undefined') {
         expect(typeof definition.env).toBe('string');

spec/ClientSDK.spec.js

@@ -2,7 +2,7 @@ var ClientSDK = require('../src/ClientSDK');
 
 describe('ClientSDK', () => {
   it('should properly parse the SDK versions', () => {
-    let clientSDKFromVersion = ClientSDK.fromString;
+    const clientSDKFromVersion = ClientSDK.fromString;
     expect(clientSDKFromVersion('i1.1.1')).toEqual({
       sdk: 'i',
       version: '1.1.1'