Function extend

samples/common/codehighlight/codemirror.js:7524–7542

(e)

    var counter = 0;

    function extend(e) {
      var curCount = ++counter;
      var cur = posFromMouse(cm, e, true, behavior.unit == "rectangle");
      if (!cur) { return }
      if (cmp(cur, lastPos) != 0) {
        cm.curOp.focus = activeElt();
        extendTo(cur);
        var visible = visibleLines(display, doc);
        if (cur.line >= visible.to || cur.line < visible.from)
          { setTimeout(operation(cm, function () {if (counter == curCount) { extend(e); }}), 150); }
      } else {
        var outside = e.clientY < editorSize.top ? -20 : e.clientY > editorSize.bottom ? 20 : 0;
        if (outside) { setTimeout(operation(cm, function () {
          if (counter != curCount) { return }
          display.scroller.scrollTop += outside;
          extend(e);
        }), 50); }
      }
    }

    function done(e) {
      cm.state.selectingText = false;