Exceptions aren't shown when using apython in Ubuntu

[rogpeppe]

apython doesn't seem to show exceptions when they happen.
For example:

% apython
Python 3.5.2 (default, Nov 17 2016, 17:05:23) 
[GCC 5.4.0 20160609] on linux
Type "help", "copyright", "credits" or "license" for more information.
---
This console is running in an asyncio event loop.
It allows you to wait for coroutines using the 'await' syntax.
Try: await asyncio.sleep(1, result=3, loop=loop)
---
>>> raise Exception('foo')
>>>

I was hoping to be able to use apython for interactively debugging async Python code, but this makes it not nearly so useful.

[vxgmichel]

Thanks for your report! I didn't manage to reproduce this issue on a linux terminal. Are you using windows?

[rogpeppe]

I'm using Ubuntu 16.04, and I just re-verified that the issue happens. I'm not sure
what version of apython I'm using though - I just followed standard install instructions.

[vxgmichel]

I've been able to reproduce the issue, it's actually caused by the ubuntu "apport" thing.

It is now fixed starting with release v0.1.5.

Make sure you update your aioconsole package by running:

$ pip3 install -U aioconsole

Thanks again for the report!

[rogpeppe]

Thanks very much. This seems to fix the issue for me. I'd love to see a more detailed description of what was going on here though. How was apport interfering with apython's exception reporting?

[vxgmichel]

That's because I was relying on code.InteractiveInterpreter.showtraceback, which performs the following check:

if sys.excepthook is sys.__excepthook__:
    self.write(''.join(lines))

Because of apport, sys.excepthook is sys.__excepthook__ evaluates to False in ubuntu.

See the source here.

[rogpeppe]

Thanks, that's very good to know.