User:Enterprisey/diff-permalink.js

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This user script seems to have a documentation page at User:Enterprisey/diff-permalink.

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// <nowiki>
$( function () {
    var suffix = mw.config.get( "wgDiffNewId" );
    var page;
    if( suffix ) {
        if( document.getElementsByClassName( "diff-multi" ).length )
            suffix = mw.config.get( "wgDiffOldId" ) + "/" + suffix;
        page = "Special:Diff/" + suffix;
    } else {
        var oldidMatch = /&oldid=(\d+)/.exec( window.location.search );
        if( oldidMatch ) {
            page = "Special:Permalink/" + oldidMatch[1];
        } else {

            // nothing to do here
            return;
        }
    }

    var permalinkEl = $( "<input>" ).val( page )
        .click( function () { this.select(); document.execCommand( "copy" ); } );
    permalinkEl.attr( "size", permalinkEl.val().length ); // resize to diff length
    if( suffix ) {
        $( "#bodyContent" ).prepend( permalinkEl )
            .prepend( "Permalink to this diff: " );
    } else {
        $( "#contentSub" ).after( "Permalink to this oldid: " ).after( permalinkEl );
    }
} );
// </nowiki>