User:Ilmari Karonen/rollbacksummary.js

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// Prompt for an edit summary when clicking a rollback link

$(function () {
    var serverRe = mw.config.get('wgServer').replace(/([^A-Za-z0-9_])/g, "\\$1"); 
    var scriptRe = mw.config.get('wgScript').replace(/([^A-Za-z0-9_])/g, "\\$1"); 
    var rollbackRe = new RegExp ("^(" + serverRe + ")?" + scriptRe + "\\?([^#]*&)?action=rollback(&|$)");
    var promptSummary = function () {
        var summary = prompt("Enter rollback summary (or leave as \"default\" to use default summary):", "default");
        if (summary == null || summary == "") return false;
        if (summary == "default") return true;
        this.href = this.href.replace("?", "?summary=" + encodeURIComponent(summary) + "&");
        return true;
    };
    var links = document.getElementsByTagName("a");
    for (var i = 0; i < links.length; i++) {
        if (rollbackRe.test(links[i].href)) links[i].onclick = promptSummary;
    }
});