resources/src/startup.js

   1 /**
   2  * This file is where we decide whether to initialise the Grade A run-time.
   3  *
   4  * - Beware: This file MUST parse without errors on even the most ancient of browsers!
   5  */
   6
   7 /* global mw, isCompatible, $VARS, $CODE */
   8
   9 /**
  10  * See <https://www.mediawiki.org/wiki/Compatibility#Browsers>
  11  *
  12  * Capabilities required for modern run-time:
  13  * - ECMAScript 5
  14  * - DOM Level 4 & Selectors API Level 1
  15  * - HTML5 & Web Storage
  16  * - DOM Level 2 Events
  17  *
  18  * Browsers we support in our modern run-time (Grade A):
  19  * - Chrome 13+
  20  * - IE 11+
  21  * - Firefox 4+
  22  * - Safari 5+
  23  * - Opera 15+
  24  * - Mobile Safari 6.0+ (iOS 6+)
  25  * - Android 4.1+
  26  *
  27  * Browsers we support in our no-javascript run-time (Grade C):
  28  * - Chrome 1+
  29  * - IE 6+
  30  * - Firefox 3+
  31  * - Safari 3+
  32  * - Opera 15+
  33  * - Mobile Safari 5.0+ (iOS 4+)
  34  * - Android 2.0+
  35  * - WebOS < 1.5
  36  * - PlayStation
  37  * - Symbian-based browsers
  38  * - NetFront-based browser
  39  * - Opera Mini
  40  * - Nokia's Ovi Browser
  41  * - MeeGo's browser
  42  * - Google Glass
  43  * - UC Mini (speed mode on)
  44  *
  45  * Other browsers that pass the check are considered Grade X.
  46  *
  47  * @param {string} [str] User agent, defaults to navigator.userAgent
  48  * @return {boolean} User agent is compatible with MediaWiki JS
  49  */
  50 window.isCompatible = function ( str ) {
  51         var ua = str || navigator.userAgent;
  52         return !!(
  53                 // https://caniuse.com/#feat=es5
  54                 // https://caniuse.com/#feat=use-strict
  55                 // https://caniuse.com/#feat=json / https://phabricator.wikimedia.org/T141344#2784065
  56                 ( function () {
  57                         'use strict';
  58                         return !this && !!Function.prototype.bind && !!window.JSON;
  59                 }() ) &&
  60
  61                 // https://caniuse.com/#feat=queryselector
  62                 'querySelector' in document &&
  63
  64                 // https://caniuse.com/#feat=namevalue-storage
  65                 // https://developer.blackberry.com/html5/apis/v1_0/localstorage.html
  66                 // https://blog.whatwg.org/this-week-in-html-5-episode-30
  67                 'localStorage' in window &&
  68
  69                 // https://caniuse.com/#feat=addeventlistener
  70                 'addEventListener' in window &&
  71
  72                 // Hardcoded exceptions for browsers that pass the requirement but we don't want to
  73                 // support in the modern run-time.
  74                 // Note: Please extend the regex instead of adding new ones
  75                 !(
  76                         ua.match( /MSIE 10|webOS\/1\.[0-4]|SymbianOS|Series60|NetFront|Opera Mini|S40OviBrowser|MeeGo|Android.+Glass|^Mozilla\/5\.0 .+ Gecko\/$|googleweblight/ ) ||
  77                         ua.match( /PlayStation/i )
  78                 )
  79         );
  80 };
  81
  82 // Conditional script injection
  83 ( function () {
  84         var NORLQ, script;
  85         if ( !isCompatible() ) {
  86                 // Undo class swapping in case of an unsupported browser.
  87                 // See ResourceLoaderClientHtml::getDocumentAttributes().
  88                 document.documentElement.className = document.documentElement.className
  89                         .replace( /(^|\s)client-js(\s|$)/, '$1client-nojs$2' );
  90
  91                 NORLQ = window.NORLQ || [];
  92                 while ( NORLQ.length ) {
  93                         NORLQ.shift()();
  94                 }
  95                 window.NORLQ = {
  96                         push: function ( fn ) {
  97                                 fn();
  98                         }
  99                 };
 100
 101                 // Clear and disable the other queue
 102                 window.RLQ = {
 103                         // No-op
 104                         push: function () {}
 105                 };
 106
 107                 return;
 108         }
 109
 110         /**
 111          * The $CODE and $VARS placeholders are substituted in ResourceLoaderStartUpModule.php.
 112          */
 113         function startUp() {
 114                 mw.config = new mw.Map( $VARS.wgLegacyJavaScriptGlobals );
 115
 116                 $CODE.registrations();
 117
 118                 mw.config.set( $VARS.configuration );
 119
 120                 // Must be after mw.config.set because these callbacks may use mw.loader which
 121                 // needs to have values 'skin', 'debug' etc. from mw.config.
 122                 // eslint-disable-next-line vars-on-top
 123                 var RLQ = window.RLQ || [];
 124                 while ( RLQ.length ) {
 125                         RLQ.shift()();
 126                 }
 127                 window.RLQ = {
 128                         push: function ( fn ) {
 129                                 fn();
 130                         }
 131                 };
 132
 133                 // Clear and disable the other queue
 134                 window.NORLQ = {
 135                         // No-op
 136                         push: function () {}
 137                 };
 138         }
 139
 140         if ( window.performance && performance.mark ) {
 141                 performance.mark( 'mwStartup' );
 142         }
 143         script = document.createElement( 'script' );
 144         script.src = $VARS.baseModulesUri;
 145         script.onload = function () {
 146                 // Clean up
 147                 script.onload = null;
 148                 script = null;
 149                 // Callback
 150                 startUp();
 151         };
 152         document.head.appendChild( script );
 153 }() );