resourceloader: Remove warning for handled localStorage error

[lhc/web/wiklou.git] / resources / src / startup / mediawiki.js

diff --git a/resources/src/startup/mediawiki.js b/resources/src/startup/mediawiki.js
index 967c529..c08d259 100644 (file)
--- a/resources/src/startup/mediawiki.js
+++ b/resources/src/startup/mediawiki.js
@@ -1102,6 +1102,12 @@
                         * @param {Function} [callback] Callback to run after request resolution
                         */
                        function addScript( src, callback ) {
+                               // Use a <script> element rather than XHR. Using XHR changes the request
+                               // headers (potentially missing a cache hit), and reduces caching in general
+                               // since browsers cache XHR much less (if at all). And XHR means we retrieve
+                               // text, so we'd need to eval, which then messes up line numbers.
+                               // The drawback is that <script> does not offer progress events, feedback is
+                               // only given after downloading, parsing, and execution have completed.
                                var script = document.createElement( 'script' );
                                script.src = src;
                                script.onload = script.onerror = function () {
@@ -2235,10 +2241,8 @@
                                                                return;
                                                        }
                                                } catch ( e ) {
-                                                       mw.trackError( 'resourceloader.exception', {
-                                                               exception: e,
-                                                               source: 'store-localstorage-init'
-                                                       } );
+                                                       // Perhaps localStorage was disabled by the user, or got corrupted.
+                                                       // See point 3 and 4 below. (T195647)
                                                }
 
                                                // If we get here, one of four things happened:
@@ -2341,9 +2345,11 @@
 
                                                try {
                                                        if ( typeof descriptor.script === 'function' ) {
+                                                               // Function literal: cast to string
                                                                encodedScript = String( descriptor.script );
                                                        } else if (
-                                                               // Plain object: an object that is not null and is not an array
+                                                               // Plain object: serialise as object literal (not JSON),
+                                                               // making sure to preserve the functions.
                                                                typeof descriptor.script === 'object' &&
                                                                descriptor.script &&
                                                                !Array.isArray( descriptor.script )
@@ -2358,6 +2364,7 @@
                                                                        } ).join( ',' ) +
                                                                        '}}';
                                                        } else {
+                                                               // Array of urls, or null.
                                                                encodedScript = JSON.stringify( descriptor.script );
                                                        }
                                                        args = [