chore: use recommended flow lint rules (#631)

Author: kumar303

.eslintrc

@@ -13,7 +13,10 @@
     "node": true,
     "es6": true
   },
-  "extends": "eslint:recommended",
+  "extends": [
+    "eslint:recommended",
+    "plugin:flowtype/recommended"
+  ],
   "ecmaFeatures": {
     "arrowFunctions": true,
     "blockBindings": true,

src/cmd/build.js

@@ -49,7 +49,7 @@ export async function getDefaultLocalizedName(
   {messageFile, manifestData}: LocalizedNameParams
 ): Promise<string> {
 
-  let messageData: string|Buffer;
+  let messageData: string | Buffer;
   let extensionName: string = manifestData.name;
 
   try {

src/cmd/run.js

@@ -306,7 +306,7 @@ export class ExtensionRunner {
     return client.installTemporaryAddon(this.sourceDir);
   }
 
-  installAsProxy(profile: FirefoxProfile): Promise<string|void> {
+  installAsProxy(profile: FirefoxProfile): Promise<string | void> {
     const {firefoxApp, sourceDir, manifestData} = this;
     return firefoxApp.installExtension(
       {

src/cmd/sign.js

@@ -133,7 +133,7 @@ export default function sign(
 
 export async function getIdFromSourceDir(
   sourceDir: string
-): Promise<string|void> {
+): Promise<string | void> {
   const filePath = path.join(sourceDir, extensionIdFile);
 
   let content;
@@ -167,8 +167,9 @@ export async function getIdFromSourceDir(
 }
 
 
-export async function saveIdToSourceDir(sourceDir: string, id: string)
-    : Promise<void> {
+export async function saveIdToSourceDir(
+  sourceDir: string, id: string
+): Promise<void> {
   const filePath = path.join(sourceDir, extensionIdFile);
   await fs.writeFile(filePath, [
     '# This file was created by https://github.com/mozilla/web-ext',

src/errors.js

@@ -89,7 +89,7 @@ export function onlyInstancesOf(
  *
  */
 export function onlyErrorsWithCode(
-  codeWanted: (string|number) | Array<string|number>,
+  codeWanted: (string | number) | Array<string | number>,
   errorHandler: Function
 ): Function {
   return (error) => {

src/firefox/preferences.js

@@ -5,7 +5,7 @@ import {WebExtError} from '../errors';
 // Flow Types
 
 export type FirefoxPreferences = {
-  [key: string]: bool | string | number,
+  [key: string]: boolean | string | number,
 };
 
 export type PreferencesAppName = 'firefox' | 'fennec';

src/util/is-directory.js

@@ -14,7 +14,7 @@ import {onlyErrorsWithCode} from '../errors';
  *  });
  *
  * */
-export default function isDirectory(path: string): Promise<bool> {
+export default function isDirectory(path: string): Promise<boolean> {
   return fs.stat(path)
     .then((stats) => stats.isDirectory())
     .catch(onlyErrorsWithCode(['ENOENT', 'ENOTDIR'], () => {

src/util/manifest.js

@@ -68,7 +68,7 @@ export default async function getValidatedManifest(
 }
 
 
-export function getManifestId(manifestData: ExtensionManifest): string|void {
+export function getManifestId(manifestData: ExtensionManifest): string | void {
   return manifestData.applications ?
     manifestData.applications.gecko.id : undefined;
 }