Wrong restore a cursor position in Midnight Commander

[meefik]

Midnight Commander send two command for save a cursor positon:

1. ESC 7 (DECSC)
   https://github.com/sourcelair/xterm.js/blob/b32a34b97c71539d86c5df5871b40397dc04fcf0/src/xterm.js#L2052
   xterm.js received a position X and Y correctly.
2. CSI s (ANSI.SYS)
   https://github.com/sourcelair/xterm.js/blob/b32a34b97c71539d86c5df5871b40397dc04fcf0/src/xterm.js#L2430
   xterm.js received a position X and Y always 0.

Details

• Browser and browser version: Google Chrome 52.0.2743.116 (64-bit)
• OS version: Debian 8
• xterm.js version: b32a34b

Steps to reproduce

1. Run demo app.
2. Execute command mc.
3. Exit from mc.
4. Cursor restored always x:0, y:0.

[parisk]

Are there any chances that this got fixed after #231?

[meefik]

No, it is not associated. I fixed this, comment out the two lines:
https://github.com/sourcelair/xterm.js/blob/b32a34b97c71539d86c5df5871b40397dc04fcf0/src/xterm.js#L2430
https://github.com/sourcelair/xterm.js/blob/b32a34b97c71539d86c5df5871b40397dc04fcf0/src/xterm.js#L2436
But I don't know what impact these changes will have.

[Santinell]

I have the same problem, but meefik's workaround don't work for me...

Details

Browser and browser version: Chrome 53.0
OS version: Ubuntu 16.04
xterm.js version: 220828f

[Santinell]

Works for me when this line is commented out:
https://github.com/sourcelair/xterm.js/blob/220828f7db9932acbd3198be5b97d81f5a7b6880/src/xterm.js#L2068

[AndrienkoAleksandr]

This bug depends on Midnight Commander version. For example for MC 4.8.15 this bug is reproducible; mc 4.8.18 - works without this issue.

[AndrienkoAleksandr]

@parisk #231 didn't fix this issue, because this is bug of the text user interface parser(we need improve this parser - InputHandler.ts).

[Tyriar]

If this only repros in an older version of MC then they probably fixed the issue on their end? The logic for save and restore cursors seems pretty foolproof to me:

  /**
   * CSI s
   *   Save cursor (ANSI.SYS).
   */
  public saveCursor(params: number[]): void {
    this._terminal.savedX = this._terminal.x;
    this._terminal.savedY = this._terminal.y;
  }


  /**
   * CSI u
   *   Restore cursor (ANSI.SYS).
   */
  public restoreCursor(params: number[]): void {
    this._terminal.x = this._terminal.savedX || 0;
    this._terminal.y = this._terminal.savedY || 0;
  }

[Santinell]

Unfortunately in Ubuntu 16.04 you can install only 4.8.15 from official repos.
For Ubuntu 14.04 version of MC is much older I think

[Tyriar]

Fixed in #728