Function setSelection

mini-code-editor/cm/lib/codemirror.js:1179–1214

(from, to, oldFrom, oldTo)

    // updateLines, since they have to be expressed in the line
    // numbers before the update.
    function setSelection(from, to, oldFrom, oldTo) {
      goalColumn = null;
      if (oldFrom == null) {oldFrom = sel.from.line; oldTo = sel.to.line;}
      if (posEq(sel.from, from) && posEq(sel.to, to)) return;
      if (posLess(to, from)) {var tmp = to; to = from; from = tmp;}

      // Skip over hidden lines.
      if (from.line != oldFrom) {
        var from1 = skipHidden(from, oldFrom, sel.from.ch);
        // If there is no non-hidden line left, force visibility on current line
        if (!from1) setLineHidden(from.line, false);
        else from = from1;
      }
      if (to.line != oldTo) to = skipHidden(to, oldTo, sel.to.ch);

      if (posEq(from, to)) sel.inverted = false;
      else if (posEq(from, sel.to)) sel.inverted = false;
      else if (posEq(to, sel.from)) sel.inverted = true;

      if (options.autoClearEmptyLines && posEq(sel.from, sel.to)) {
        var head = sel.inverted ? from : to;
        if (head.line != sel.from.line && sel.from.line < doc.size) {
          var oldLine = getLine(sel.from.line);
          if (/^\s+$/.test(oldLine.text))
            setTimeout(operation(function() {
              if (oldLine.parent && /^\s+$/.test(oldLine.text)) {
                var no = lineNo(oldLine);
                replaceRange("", {line: no, ch: 0}, {line: no, ch: oldLine.text.length});
              }
            }, 10));
        }
      }

      sel.from = from; sel.to = to;
      selectionChanged = true;
    }
    function skipHidden(pos, oldLine, oldCh) {
      function getNonHidden(dir) {
        var lNo = pos.line + dir, end = dir == 1 ? doc.size : -1;