search: Reduce skins.vector.search module size

Change I765d3bbf89 pushes the module over the configured maximum allowed
size (3 KiB, see bundlesize.config.json); shave off some bytes elsewhere
to bring it below the limit again. IMHO all of these changes should be
acceptable:

* arrow functions are already used elsewhere in this module;
* using the mw.config.get() fallback argument is normal (it slightly
  changes behavior, but I don’t think explicitly setting the search
  client or URL generator to a falsy value and expecting to get the
  default behavior should be considered supported);
* not quoting [name="search"] matches [name=title] immediately above;
* using forEach() with a function reference is still readable (initApp()
  is now called with extra arguments, but that doesn’t matter).

Change-Id: I45dda26cb59279d91804b0c2bbf12174fa78ee12

resources/skins.vector.search/instrumentation.js

@@ -64,8 +64,8 @@ function onFetchEnd( event ) {
 		// execute before the rendering steps happen (e.g. layout and paint). A
 		// nested rAF will execute after these rendering steps have completed
 		// and ensure the search results are visible to the user.
-		requestAnimationFrame( function () {
-			requestAnimationFrame( function () {
+		requestAnimationFrame( () => {
+			requestAnimationFrame( () => {
 				if ( !performance.getEntriesByName( queryMark ).length ) {
 					return;
 				}

resources/skins.vector.search/restSearchClient.js

@@ -81,8 +81,7 @@ function adaptApiResponse( config, query, restResponse, showDescription ) {
  * @return {SearchClient}
  */
 function restSearchClient( config ) {
-	const customClient = config.get( 'wgVectorSearchClient' );
-	return customClient || {
+	return config.get( 'wgVectorSearchClient', {
 		/**
 		 * @type {fetchByTitle}
 		 */
@@ -103,7 +102,7 @@ function restSearchClient( config ) {
 				fetch: searchResponsePromise
 			};
 		}
-	};
+	} );
 }
 
 module.exports = restSearchClient;

resources/skins.vector.search/skins.vector.search.js

@@ -14,7 +14,7 @@ function initApp( searchBox ) {
 		titleInput = /** @type {HTMLInputElement|null} */ (
 			searchBox.querySelector( 'input[name=title]' )
 		),
-		search = /** @type {HTMLInputElement|null} */ ( searchBox.querySelector( 'input[name="search"]' ) ),
+		search = /** @type {HTMLInputElement|null} */ ( searchBox.querySelector( 'input[name=search]' ) ),
 		searchPageTitle = titleInput && titleInput.value;
 
 	if ( !searchForm || !search || !titleInput ) {
@@ -43,10 +43,7 @@ function initApp( searchBox ) {
  * @return {void}
  */
 function main( document ) {
-	const searchBoxes = document.querySelectorAll( '.vector-search-box' );
-
-	searchBoxes.forEach( ( searchBox ) => {
-		initApp( searchBox );
-	} );
+	document.querySelectorAll( '.vector-search-box' )
+		.forEach( initApp );
 }
 main( document );

resources/skins.vector.search/urlGenerator.js

@@ -28,8 +28,7 @@
 function urlGenerator( config ) {
 	// TODO: This is a placeholder for enabling customization of the URL generator.
 	// wgVectorSearchUrlGenerator has not been defined as a config variable yet.
-	const customGenerator = config.get( 'wgVectorSearchUrlGenerator' );
-	return customGenerator || {
+	return config.get( 'wgVectorSearchUrlGenerator', {
 		/**
 		 * @type {generateUrl}
 		 */
@@ -52,7 +51,7 @@ function urlGenerator( config ) {
 
 			return articlePath + '?' + $.param( $.extend( {}, params, { search: suggestion } ) );
 		}
-	};
+	} );
 }
 
 /** @module urlGenerator */

tests/jest/restSearchClient.test.js

@@ -4,14 +4,14 @@ const jestFetchMock = require( 'jest-fetch-mock' );
 
 const mockedRequests = !process.env.TEST_LIVE_REQUESTS;
 const configMock = {
-	get: jest.fn().mockImplementation( key => {
+	get: jest.fn().mockImplementation( ( key, fallback = null ) => {
 		if ( key === 'wgScriptPath' ) {
 			return '/w';
 		}
 		if ( key === 'wgScript' ) {
 			return '/w/index.php';
 		}
-		return null;
+		return fallback;
 	} ),
 	set: jest.fn()
 };