Bug: Should respond to device attributes sequences (da1/da2)

[sazary]

when i open the demo app in this repo on my local machine, this line gets printed on top of the terminal:

warning: fish could not read response to Primary Device Attribute query after waiting for 2 seconds. This is often due to a missing feature in your terminal. See 'help terminal-compatibility' or 'man fish-terminal-compatibility'. This fish process will no longer wait for outstanding queries, which disables some optional features.

as you can see, my default terminal is fish (version 4.2.1 on macos).

i investigated this issue and as far as i can tell it's because fish is sending a DA1 query sequence and we're dropping it in the wasm patch here.

since this repo intends to be a drop in replacement for xterm.js, this is the relevant implementation in their repo (link)

  /**
   * CSI Ps c  Send Device Attributes (Primary DA).
   *     Ps = 0  or omitted -> request attributes from terminal.  The
   *     response depends on the decTerminalID resource setting.
   *     -> CSI ? 1 ; 2 c  (``VT100 with Advanced Video Option'')
   *     -> CSI ? 1 ; 0 c  (``VT101 with No Options'')
   *     -> CSI ? 6 c  (``VT102'')
   *     -> CSI ? 6 0 ; 1 ; 2 ; 6 ; 8 ; 9 ; 1 5 ; c  (``VT220'')
   *   The VT100-style response parameters do not mean anything by
   *   themselves.  VT220 parameters do, telling the host what fea-
   *   tures the terminal supports:
   *     Ps = 1  -> 132-columns.
   *     Ps = 2  -> Printer.
   *     Ps = 6  -> Selective erase.
   *     Ps = 8  -> User-defined keys.
   *     Ps = 9  -> National replacement character sets.
   *     Ps = 1 5  -> Technical characters.
   *     Ps = 2 2  -> ANSI color, e.g., VT525.
   *     Ps = 2 9  -> ANSI text locator (i.e., DEC Locator mode).
   *
   * @vt: #Y CSI DA1   "Primary Device Attributes"     "CSI c"  "Send primary device attributes."
   *
   *
   * TODO: fix and cleanup response
   */
  public sendDeviceAttributesPrimary(params: IParams): boolean {
    if (params.params[0] > 0) {
      return true;
    }
    if (this._is('xterm') || this._is('rxvt-unicode') || this._is('screen')) {
      this._coreService.triggerDataEvent(C0.ESC + '[?1;2c');
    } else if (this._is('linux')) {
      this._coreService.triggerDataEvent(C0.ESC + '[?6c');
    }
    return true;
  }

  /**
   * CSI > Ps c
   *   Send Device Attributes (Secondary DA).
   *     Ps = 0  or omitted -> request the terminal's identification
   *     code.  The response depends on the decTerminalID resource set-
   *     ting.  It should apply only to VT220 and up, but xterm extends
   *     this to VT100.
   *     -> CSI  > Pp ; Pv ; Pc c
   *   where Pp denotes the terminal type
   *     Pp = 0  -> ``VT100''.
   *     Pp = 1  -> ``VT220''.
   *   and Pv is the firmware version (for xterm, this was originally
   *   the XFree86 patch number, starting with 95).  In a DEC termi-
   *   nal, Pc indicates the ROM cartridge registration number and is
   *   always zero.
   * More information:
   *   xterm/charproc.c - line 2012, for more information.
   *   vim responds with ^[[?0c or ^[[?1c after the terminal's response (?)
   *
   * @vt: #Y CSI DA2   "Secondary Device Attributes"   "CSI > c" "Send primary device attributes."
   *
   *
   * TODO: fix and cleanup response
   */
  public sendDeviceAttributesSecondary(params: IParams): boolean {
    if (params.params[0] > 0) {
      return true;
    }
    // xterm and urxvt
    // seem to spit this
    // out around ~370 times (?).
    if (this._is('xterm')) {
      this._coreService.triggerDataEvent(C0.ESC + '[>0;276;0c');
    } else if (this._is('rxvt-unicode')) {
      this._coreService.triggerDataEvent(C0.ESC + '[>85;95;0c');
    } else if (this._is('linux')) {
      // not supported by linux console.
      // linux console echoes parameters.
      this._coreService.triggerDataEvent(params.params[0] + 'c');
    } else if (this._is('screen')) {
      this._coreService.triggerDataEvent(C0.ESC + '[>83;40003;0c');
    }
    return true;
  }