logger.catch decorator doesn't print pretty traceback on async functions

[Fak3]

loguru v0.2.5
Minimal example:

from loguru import logger

@logger.catch
async def xxx():
    x = 3 / 0
        
asyncio.run(xxx())

Prints just plain traceback:

Traceback (most recent call last):
  File "./download.py", line 201, in <module>
    asyncio.run(xxx())
  File "/usr/lib64/python3.7/asyncio/runners.py", line 43, in run
    return loop.run_until_complete(main)
  File "/usr/lib64/python3.7/asyncio/base_events.py", line 584, in run_until_complete
    return future.result()
  File "./download.py", line 199, in xxx
    x = 3 / 0
ZeroDivisionError: division by zero

But if i catch the exception and log it from the function, i get pretty traceback, including values of variables:

from loguru import logger

async def xxx():
    zero = 0
    try:
        x = 3 / zero
    except:
        logger.exception('boom')
        
asyncio.run(xxx())

Prints:

2019-03-30 18:47:43.563 | ERROR    | __main__:xxx:202 - boom
Traceback (most recent call last):

  File "./download.py", line 204, in <module>
    asyncio.run(xxx())
    │       │   └ <function xxx at 0x7f7547453ea0>
    │       └ <function run at 0x7f7547a4bb70>
    └ <module 'asyncio' from '/usr/lib64/python3.7/asyncio/__init__.py'>

  File "/usr/lib64/python3.7/asyncio/runners.py", line 43, in run
    return loop.run_until_complete(main)
           │    │                  └ <coroutine object xxx at 0x7f7547e33ec8>
           │    └ <bound method BaseEventLoop.run_until_complete of <_UnixSelectorEventLoop running=True closed=False debug=False>>
           └ <_UnixSelectorEventLoop running=True closed=False debug=False>
  File "/usr/lib64/python3.7/asyncio/base_events.py", line 571, in run_until_complete
    self.run_forever()
    │    └ <bound method BaseEventLoop.run_forever of <_UnixSelectorEventLoop running=True closed=False debug=False>>
    └ <_UnixSelectorEventLoop running=True closed=False debug=False>
  File "/usr/lib64/python3.7/asyncio/base_events.py", line 539, in run_forever
    self._run_once()
    │    └ <bound method BaseEventLoop._run_once of <_UnixSelectorEventLoop running=True closed=False debug=False>>
    └ <_UnixSelectorEventLoop running=True closed=False debug=False>
  File "/usr/lib64/python3.7/asyncio/base_events.py", line 1775, in _run_once
    handle._run()
    │      └ <bound method Handle._run of <Handle <TaskStepMethWrapper object at 0x7f75474516d8>()>>
    └ <Handle <TaskStepMethWrapper object at 0x7f75474516d8>()>
  File "/usr/lib64/python3.7/asyncio/events.py", line 88, in _run
    self._context.run(self._callback, *self._args)
    │    │        │   │    │           │    └ ()
    │    │        │   │    │           └ <Handle <TaskStepMethWrapper object at 0x7f75474516d8>()>
    │    │        │   │    └ <TaskStepMethWrapper object at 0x7f75474516d8>
    │    │        │   └ <Handle <TaskStepMethWrapper object at 0x7f75474516d8>()>
    │    │        └ <built-in method run of Context object at 0x7f75473d75e8>
    │    └ <Context object at 0x7f75473d75e8>
    └ <Handle <TaskStepMethWrapper object at 0x7f75474516d8>()>

> File "./download.py", line 200, in xxx
    x = 3 / zero
            └ 0

ZeroDivisionError: division by zero

[Delgan]

Thanks for the bug report. 😉

I admit I never tried to decorate a coroutine. Today I learned that to wrap an async function, well, the wrapper function need to be async too.

This should be easily fixed.

[Delgan]

This will be fixed in v0.3.0.

I also added support for decorating generator functions. It should also be possible to decorate asynchronous generators, but I prefer to better understand all the async / await stuff before implementing it.