Merge "mediawiki.util: Add debounce() function"

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

diff --git a/resources/src/mediawiki.util/util.js b/resources/src/mediawiki.util/util.js
index 57843cb..8521664 100644 (file)
--- a/resources/src/mediawiki.util/util.js
+++ b/resources/src/mediawiki.util/util.js
@@ -83,6 +83,27 @@ util = {
                return escapeIdInternal( str, config.FragmentMode[ 0 ] );
        },
 
+       /**
+        * Return a wrapper function that is debounced for the given duration.
+        *
+        * When it is first called, a timeout is scheduled. If before the timer
+        * is reached the wrapper is called again, it gets rescheduled for the
+        * same duration from now until it stops being called. The original function
+        * is called from the "tail" of such chain, with the last set of arguments.
+        *
+        * @since 1.34
+        * @param {number} delay Time in milliseconds
+        * @param {Function} callback
+        * @return {Function}
+        */
+       debounce: function ( delay, callback ) {
+               var timeout;
+               return function () {
+                       clearTimeout( timeout );
+                       timeout = setTimeout( Function.prototype.apply.bind( callback, this, arguments ), delay );
+               };
+       },
+
        /**
         * Encode page titles for use in a URL
         *