Function drawSelectionRange

static/libs/codemirror.js:3100–3190

(cm, range$$1, output)

// Draws the given range as a highlighted selection
function drawSelectionRange(cm, range$$1, output) {
  var display = cm.display, doc = cm.doc;
  var fragment = document.createDocumentFragment();
  var padding = paddingH(cm.display), leftSide = padding.left;
  var rightSide = Math.max(display.sizerWidth, displayWidth(cm) - display.sizer.offsetLeft) - padding.right;
  var docLTR = doc.direction == "ltr";

  function add(left, top, width, bottom) {
    if (top < 0) { top = 0; }
    top = Math.round(top);
    bottom = Math.round(bottom);
    fragment.appendChild(elt("div", null, "CodeMirror-selected", ("position: absolute; left: " + left + "px;\n                             top: " + top + "px; width: " + (width == null ? rightSide - left : width) + "px;\n                             height: " + (bottom - top) + "px")));
  }

  function drawForLine(line, fromArg, toArg) {
    var lineObj = getLine(doc, line);
    var lineLen = lineObj.text.length;
    var start, end;
    function coords(ch, bias) {
      return charCoords(cm, Pos(line, ch), "div", lineObj, bias)
    }

    function wrapX(pos, dir, side) {
      var extent = wrappedLineExtentChar(cm, lineObj, null, pos);
      var prop = (dir == "ltr") == (side == "after") ? "left" : "right";
      var ch = side == "after" ? extent.begin : extent.end - (/\s/.test(lineObj.text.charAt(extent.end - 1)) ? 2 : 1);
      return coords(ch, prop)[prop]
    }

    var order = getOrder(lineObj, doc.direction);
    iterateBidiSections(order, fromArg || 0, toArg == null ? lineLen : toArg, function (from, to, dir, i) {
      var ltr = dir == "ltr";
      var fromPos = coords(from, ltr ? "left" : "right");
      var toPos = coords(to - 1, ltr ? "right" : "left");

      var openStart = fromArg == null && from == 0, openEnd = toArg == null && to == lineLen;
      var first = i == 0, last = !order || i == order.length - 1;
      if (toPos.top - fromPos.top <= 3) { // Single line
        var openLeft = (docLTR ? openStart : openEnd) && first;
        var openRight = (docLTR ? openEnd : openStart) && last;
        var left = openLeft ? leftSide : (ltr ? fromPos : toPos).left;
        var right = openRight ? rightSide : (ltr ? toPos : fromPos).right;
        add(left, fromPos.top, right - left, fromPos.bottom);
      } else { // Multiple lines
        var topLeft, topRight, botLeft, botRight;
        if (ltr) {
          topLeft = docLTR && openStart && first ? leftSide : fromPos.left;
          topRight = docLTR ? rightSide : wrapX(from, dir, "before");
          botLeft = docLTR ? leftSide : wrapX(to, dir, "after");
          botRight = docLTR && openEnd && last ? rightSide : toPos.right;
        } else {
          topLeft = !docLTR ? leftSide : wrapX(from, dir, "before");
          topRight = !docLTR && openStart && first ? rightSide : fromPos.right;
          botLeft = !docLTR && openEnd && last ? leftSide : toPos.left;
          botRight = !docLTR ? rightSide : wrapX(to, dir, "after");
        }
        add(topLeft, fromPos.top, topRight - topLeft, fromPos.bottom);
        if (fromPos.bottom < toPos.top) { add(leftSide, fromPos.bottom, null, toPos.top); }