Session restore: "named views" is None

[chimerax-bug-report@…]

The following bug report has been submitted:
Platform:        Linux-3.10.0-957.21.3.el7.x86_64-x86_64-with-centos-7.6.1810-Core
ChimeraX Version: 0.9 (2019-06-06)
Description
(Describe the actions that caused this problem to occur here)

Log:
Startup Messages  
---  
warning | 'clip' is a prefix of an existing command 'clipper'  
  
UCSF ChimeraX version: 0.9 (2019-06-06)  
© 2016-2019 Regents of the University of California. All rights reserved.  
How to cite UCSF ChimeraX  

> open
/home/Dutzler/VKalienkova/Pictures/nha_paper/final/figure1-3_chinerax_final.cxs

Unable to restore session, resetting.  
  
Traceback (most recent call last):  
File "/programs/x86_64-linux/chimerax/0.9/lib/python3.7/site-
packages/chimerax/core/session.py", line 579, in restore  
self.add_state_manager(name, data)  
File "/programs/x86_64-linux/chimerax/0.9/lib/python3.7/site-
packages/chimerax/core/session.py", line 429, in add_state_manager  
raise ValueError('container "%s" of type "%s" does not have snapshot methods
and does not have clear method' % (tag, str(type(container))))  
ValueError: container "named views" of type "<class 'NoneType'>" does not have
snapshot methods and does not have clear method  
  
opened ChimeraX session  

> open /home/Dutzler/VKalienkova/Pictures/nha_paper/final/figure1_2_new.cxs

Unable to restore session, resetting.  
  
Traceback (most recent call last):  
File "/programs/x86_64-linux/chimerax/0.9/lib/python3.7/site-
packages/chimerax/core/session.py", line 579, in restore  
self.add_state_manager(name, data)  
File "/programs/x86_64-linux/chimerax/0.9/lib/python3.7/site-
packages/chimerax/core/session.py", line 429, in add_state_manager  
raise ValueError('container "%s" of type "%s" does not have snapshot methods
and does not have clear method' % (tag, str(type(container))))  
ValueError: container "named views" of type "<class 'NoneType'>" does not have
snapshot methods and does not have clear method  
  
opened ChimeraX session  




OpenGL version: 3.3.0 NVIDIA 390.87
OpenGL renderer: Quadro 4000/PCIe/SSE2
OpenGL vendor: NVIDIA Corporation

[pett]

Seems like a restore of an old session where we still allowed 'None's to be saved. Unless we want a zillion bug reports like this, maybe this shouldn't raise ValueError (LimitationError, and with more explanatory text?).

[Greg Couch]

This is most likely due to a bug in the original session saving. Since the session won't be saved in the first place now, and because we're not seeing many of these errors, we're not going to change any code. Instead we will work with the user and apologize directly.

Did add information about the current ChimeraX (version, commit, date, branch) to session metadata.