Clarify "while blocked" where something else could be "blocked" too
[lhc/web/wiklou.git] / resources / src / startup.js
1 /**
2 * Code in this file MUST work on even the most ancient of browsers!
3 *
4 * This file is where we decide whether to initialise the modern run-time.
5 */
6 /*jshint unused: false */
7 /*globals mw, RLQ: true, NORLQ: true, $VARS, $CODE, performance */
8
9 var mediaWikiLoadStart = ( new Date() ).getTime(),
10
11 mwPerformance = ( window.performance && performance.mark ) ? performance : {
12 mark: function () {}
13 };
14
15 mwPerformance.mark( 'mwLoadStart' );
16
17 /**
18 * See <https://www.mediawiki.org/wiki/Compatibility#Browsers>
19 *
20 * Capabilities required for modern run-time:
21 * - DOM Level 4 & Selectors API Level 1
22 * - HTML5 & Web Storage
23 * - DOM Level 2 Events
24 *
25 * Browsers we support in our modern run-time (Grade A):
26 * - Chrome
27 * - IE 9+
28 * - Firefox 3.5+
29 * - Safari 4+
30 * - Opera 10.5+
31 * - Mobile Safari (iOS 1+)
32 * - Android 2.0+
33 *
34 * Browsers we support in our no-javascript run-time (Grade C):
35 * - IE 6+
36 * - Firefox 3+
37 * - Safari 3+
38 * - Opera 10+
39 * - WebOS < 1.5
40 * - PlayStation
41 * - Symbian-based browsers
42 * - NetFront-based browser
43 * - Opera Mini
44 * - Nokia's Ovi Browser
45 * - MeeGo's browser
46 * - Google Glass
47 *
48 * Other browsers that pass the check are considered Grade X.
49 */
50 function isCompatible( str ) {
51 var ua = str || navigator.userAgent;
52 return !!(
53 // http://caniuse.com/#feat=queryselector
54 'querySelector' in document
55
56 // http://caniuse.com/#feat=namevalue-storage
57 // https://developer.blackberry.com/html5/apis/v1_0/localstorage.html
58 // https://blog.whatwg.org/this-week-in-html-5-episode-30
59 && 'localStorage' in window
60
61 // http://caniuse.com/#feat=addeventlistener
62 && 'addEventListener' in window
63
64 // Hardcoded exceptions for browsers that pass the requirement but we don't want to
65 // support in the modern run-time.
66 && !(
67 ua.match( /webOS\/1\.[0-4]|SymbianOS|Series60|NetFront|Opera Mini|S40OviBrowser|MeeGo|Android.+Glass/ ) ||
68 ua.match( /PlayStation/i )
69 )
70 );
71 }
72
73 // Conditional script injection
74 ( function () {
75 var NORLQ, script;
76 if ( !isCompatible() ) {
77 // Undo class swapping in case of an unsupported browser.
78 // See ResourceLoaderClientHtml::getDocumentAttributes().
79 document.documentElement.className = document.documentElement.className
80 .replace( /(^|\s)client-js(\s|$)/, '$1client-nojs$2' );
81
82 NORLQ = window.NORLQ || [];
83 while ( NORLQ.length ) {
84 NORLQ.shift()();
85 }
86 window.NORLQ = {
87 push: function ( fn ) {
88 fn();
89 }
90 };
91
92 // Clear and disable the other queue
93 window.RLQ = {
94 // No-op
95 push: function () {}
96 };
97
98 return;
99 }
100
101 /**
102 * The $CODE and $VARS placeholders are substituted in ResourceLoaderStartUpModule.php.
103 */
104 function startUp() {
105 mw.config = new mw.Map( $VARS.wgLegacyJavaScriptGlobals );
106
107 $CODE.registrations();
108
109 mw.config.set( $VARS.configuration );
110
111 // Must be after mw.config.set because these callbacks may use mw.loader which
112 // needs to have values 'skin', 'debug' etc. from mw.config.
113 var RLQ = window.RLQ || [];
114 while ( RLQ.length ) {
115 RLQ.shift()();
116 }
117 window.RLQ = {
118 push: function ( fn ) {
119 fn();
120 }
121 };
122
123 // Clear and disable the other queue
124 window.NORLQ = {
125 // No-op
126 push: function () {}
127 };
128 }
129
130 script = document.createElement( 'script' );
131 script.src = $VARS.baseModulesUri;
132 script.onload = script.onreadystatechange = function () {
133 if ( !script.readyState || /loaded|complete/.test( script.readyState ) ) {
134 // Clean up
135 script.onload = script.onreadystatechange = null;
136 script = null;
137 // Callback
138 startUp();
139 }
140 };
141 document.getElementsByTagName( 'head' )[ 0 ].appendChild( script );
142 }() );