Xpra: Ticket #2439: window_source.py py3 incompatibility

Hi, I haven't found a ticket for this, sorry if it is a dup. When I open a menu in window, I get this stacktrace in the log:

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 1450, in expire_delayed_region
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 1614, in may_send_delayed
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 1625, in do_send_delayed
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 1643, in send_delayed_regions
    self.do_send_delayed_regions(dr.damage_time, dr.regions, dr.encoding, dr.options)
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_video_source.py", line 737, in do_send_delayed_regions
    WindowSource.do_send_delayed_regions(self, damage_time, regions, coding, options)
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 1713, in do_send_delayed_regions
    send_full_window_update("merged region covers almost the whole window")
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 1654, in send_full_window_update
    actual_encoding = get_encoding(ww, wh)
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 1651, in get_encoding
    return get_best_encoding(w, h, speed, quality, coding)
  File "/usr/lib/python3/dist-packages/xpra/server/window/window_source.py", line 924, in get_auto_encoding
    return (x for x in co if x!="rgb").next()
AttributeError: 'generator' object has no attribute 'next'

This should be next( ... ) to be compatible with python 3.

Wed, 09 Oct 2019 05:26:50 GMT - Antoine Martin: status changed; resolution set

Thanks for reporting this. Fixed in r24102.

Out of curiosity, how did you manage to trigger this? This fallback option should almost never be used, as most clients will be using webp or jpeg before falling through to this code.

Wed, 09 Oct 2019 06:36:20 GMT - Harald Schilly:

This is happening on X11 support to get an idea what it does or try it yourself.

However, I'm wondering about this fall through. Maybe there is actually something missing/a bug in how CoCalc is using this.

Wed, 09 Oct 2019 06:39:19 GMT - Antoine Martin:

IIRC, cocalc is using a forked version that lacks a number of improvements made since the fork, probably including some encodings like webp.

Sat, 23 Jan 2021 05:51:19 GMT - migration script:

this ticket has been moved to: https://github.com/Xpra-org/xpra/issues/2439