Shell useless after most errors

[goddard@…]

The following bug report has been submitted:
Platform:        Darwin-17.7.0-x86_64-i386-64bit
ChimeraX Version: 0.9 (2019-04-17)
Description
After importing a non-existent module in the shell "import nothing", the shell is broken and every statement gives "Error: execution aborted".

Here is example shell output

Jupyter QtConsole 4.4.3

Current ChimeraX session available as 'session'.

Python 3.7.2 (default, Apr 17 2019, 02:28:29) 
Type 'copyright', 'credits' or 'license' for more information
IPython 7.4.0 -- An enhanced Interactive Python. Type '?' for help.

import nothing
---------------------------------------------------------------------------
ModuleNotFoundError                       Traceback (most recent call last)
<ipython-input-1-dce2e6e450b9> in <module>
----> 1 import nothing

ModuleNotFoundError: No module named 'nothing'

import nothing
ERROR: execution aborted

1+2
ERROR: execution aborted


Log:
UCSF ChimeraX version: 0.9 (2019-04-17)  
© 2016-2019 Regents of the University of California. All rights reserved.  
How to cite UCSF ChimeraX  

> toolshed show Shell

Failed to send bug report. Error while sending follows:  

Traceback (most recent call last):  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-
packages/chimerax/bug_reporter/bug_reporter_gui.py", line 231, in submit  
errcode, errmsg, headers, body = post_multipart_formdata(BUG_HOST,
BUG_SELECTOR, fields)  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-
packages/chimerax/bug_reporter/post_form.py", line 37, in
post_multipart_formdata  
h.request('POST', url, body=body, headers={'Content-type': content_type})  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/http/client.py",
line 1229, in request  
self._send_request(method, url, body, headers, encode_chunked)  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/http/client.py",
line 1275, in _send_request  
self.endheaders(body, encode_chunked=encode_chunked)  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/http/client.py",
line 1224, in endheaders  
self._send_output(message_body, encode_chunked=encode_chunked)  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/http/client.py",
line 1016, in _send_output  
self.send(msg)  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/http/client.py",
line 956, in send  
self.connect()  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/http/client.py",
line 928, in connect  
(self.host,self.port), self.timeout, self.source_address)  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/socket.py",
line 707, in create_connection  
for res in getaddrinfo(host, port, 0, SOCK_STREAM):  
File "/Users/goddard/Desktop/ChimeraX Apr 17
2019.app/Contents/Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/socket.py",
line 748, in getaddrinfo  
for res in _socket.getaddrinfo(host, port, family, type, proto, flags):  
socket.gaierror: [Errno 8] nodename nor servname provided, or not known  




OpenGL version: 4.1 NVIDIA-10.32.0 355.11.10.10.40.102
OpenGL renderer: NVIDIA GeForce GT 650M OpenGL Engine
OpenGL vendor: NVIDIA Corporation

[goddard@…]

In fact after any error, for example a syntax error, in the shell (menu Tools / General / Shell), the shell no longer functions.

Jupyter QtConsole 4.4.3

Current ChimeraX session available as 'session'.

Python 3.7.2 (default, Apr 17 2019, 02:28:29) 
Type 'copyright', 'credits' or 'license' for more information
IPython 7.4.0 -- An enhanced Interactive Python. Type '?' for help.

some syntax error
  File "<ipython-input-1-5fd90c0e49ac>", line 1
    some syntax error
              ^
SyntaxError: invalid syntax


1+2
ERROR: execution aborted

[Eric Pettersen]

Duplicate of #1802; adding you to cc list for that