subiquity throws a UI (navigation?) error

[Frank Heimes]

While doing a daily-live subiquity installation with edge enabled (on z/VM s390x - but I think it doesn't matter), and after auto updating subiquity and restarting it, I came across the issue:

user@workstation:~$ ssh installer@hwe0006
The authenticity of host 'hwe0006 (10.245.236.26)' can't be established.
ECDSA key fingerprint is SHA256:hyQKieG4YjVhzvxDOKoDeb7R5XWFce8NH2KYJyTxTgU.
Are you sure you want to continue connecting (yes/no/[fingerprint])? aKYEYZymvkQyes
Warning: Permanently added 'hwe0006,10.245.236.26' (ECDSA) to the list of known hosts.
installer@hwe0006's password:
Welcome to Ubuntu Focal Fossa (development branch) (GNU/Linux 5.4.0-18-generic s390x)

 * Documentation: https://help.ubuntu.com
 * Management: https://landscape.canonical.com
 * Support: https://ubuntu.com/advantage

  System information as of Wed Mar 25 08:49:30 UTC 2020

  System load: 0.31 Processes: 128
  Usage of /home: unknown Users logged in: 0
  Memory usage: 23% IPv4 address for enc600: 10.245.236.26
  Swap usage: 0%

0 updates can be installed immediately.
0 of these updates are security updates.

The programs included with the Ubuntu system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Ubuntu comes with ABSOLUTELY NO WARRANTY, to the extent permitted by
applicable law.

generating crash report
^[[Breport saved to /var/crash/1585126233.864255667.ui.crash
Traceback (most recent call last):
  File "/snap/subiquity/1574/usr/bin/subiquity", line 11, in <module>
    load_entry_point('subiquity==0.0.5', 'console_scripts', 'subiquity-tui')()
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquity/cmd/tui.py", line 152, in main
    subiquity_interface.run()
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquity/core.py", line 165, in run
    super().run()
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquitycore/core.py", line 680, in run
    self.urwid_loop.run()
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/main_loop.py", line 286, in run
    self._run()
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/main_loop.py", line 384, in _run
    self.event_loop.run()
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/main_loop.py", line 1484, in run
    reraise(*exc_info)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/compat.py", line 58, in reraise
    raise value
  File "/snap/subiquity/1574/usr/lib/python3.6/asyncio/events.py", line 145, in _run
    self._callback(*self._args)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/raw_display.py", line 404, in <lambda>
    event_loop, callback, self.get_available_raw_input())
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/raw_display.py", line 502, in parse_input
    callback(processed, processed_codes)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/main_loop.py", line 411, in _update
    self.process_input(keys)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/main_loop.py", line 511, in process_input
    k = self._topmost_widget.keypress(self.screen_size, k)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/wimp.py", line 648, in keypress
    return self._current_widget.keypress(size, key)
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquitycore/ui/container.py", line 178, in keypress
    upkey = self.focus.keypress(tsize, downkey)
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquitycore/view.py", line 87, in keypress
    key = super().keypress(size, key)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/decoration.py", line 622, in keypress
    return self._original_widget.keypress(maxvals, key)
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquitycore/ui/container.py", line 178, in keypress
    upkey = self.focus.keypress(tsize, downkey)
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquitycore/ui/container.py", line 447, in keypress
    return lb.keypress(size, key)
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquitycore/ui/container.py", line 321, in keypress
    upkey = super().keypress(size, downkey)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/listbox.py", line 999, in keypress
    key = focus_widget.keypress((maxcol,),key)
  File "/snap/subiquity/1574/lib/python3.6/site-packages/subiquitycore/ui/container.py", line 178, in keypress
    upkey = self.focus.keypress(tsize, downkey)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/decoration.py", line 622, in keypress
    return self._original_widget.keypress(maxvals, key)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/container.py", line 2271, in keypress
    key = w.keypress((mc,) + size[1:], key)
  File "/snap/subiquity/1574/usr/lib/python3/dist-packages/urwid/widget.py", line 1772, in <lambda>
    keypress = property(lambda self:get_delegate(self).keypress)
AttributeError: 'Text' object has no attribute 'keypress'
Connection to hwe0006 closed.

I was able to restart the installer manually again (by re-connection via ssh) and was also finally able to complete the installation.

The above output let's me assume that a crash file was created at install time, but after the post-install reboot I couldn't find any.
But I'm attaching entire /var/log

[Frank Heimes (fheimes)]

I didn't faced this with the tests I did based on the April 20th image.
So I tend to change the status to Fix Released.
But I'll do two more installations today ...

[Frank Heimes (fheimes)]

Even in the intense RC testing I didn't came across this issue anymore.
So I think it got fixed in between, hence closing this ticket.