Method insertLines

src/common/InputHandler.ts:1311–1333

* CSI Ps L * Insert Ps Line(s) (default = 1) (IL). * * @vt: #Y CSI IL "Insert Line" "CSI Ps L" "Insert `Ps` blank lines at active row (default=1)." * For every inserted line at the scroll top one line at the scroll bottom gets removed. * The cursor is set to the first column. *

(params: IParams)

   * IL has no effect if the cursor is outside the scroll margins.
   */
  public insertLines(params: IParams): boolean {
    this._restrictCursor();
    let param = params.params[0] || 1;

    if (this._activeBuffer.y > this._activeBuffer.scrollBottom || this._activeBuffer.y < this._activeBuffer.scrollTop) {
      return true;
    }

    const row: number = this._activeBuffer.ybase + this._activeBuffer.y;

    const scrollBottomRowsOffset = this._bufferService.rows - 1 - this._activeBuffer.scrollBottom;
    const scrollBottomAbsolute = this._bufferService.rows - 1 + this._activeBuffer.ybase - scrollBottomRowsOffset + 1;
    while (param--) {
      // test: echo -e '\e[44m\e[1L\e[0m'
      // blankLine(true) - xterm/linux behavior
      this._activeBuffer.lines.splice(scrollBottomAbsolute - 1, 1);
      this._activeBuffer.lines.splice(row, 0, this._activeBuffer.getBlankLine(this._eraseAttrData()));
    }

    this._dirtyRowTracker.markRangeDirty(this._activeBuffer.y, this._activeBuffer.scrollBottom);
    this._activeBuffer.x = 0; // see https://vt100.net/docs/vt220-rm/chapter4.html - vt220 only?
    return true;
  }

  /**
   * CSI Ps M