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Author njs
Recipients asvetlov, giampaolo.rodola, njs, yselivanov
Date 2018-01-29.04:06:16
SpamBayes Score -1.0
Marked as misclassified Yes
Message-id <>
Example (minimal version of


async def open_file():

async def main():
    async with open_file():  # Should be 'async with await open_file()'

coro = main()


Here we accidentally left out an 'await' on the call to 'open_file', so the 'async with' tries to look up 'CoroutineType.__aexit__', which obviously doesn't exist, and the program crashes with an AttributeError("__aexit__"). Yet weirdly, this doesn't trigger a warning about 'open_file' being unawaited. It should!

Yury's theory: maybe BEFORE_ASYNC_WITH's error-handling path is forgetting to DECREF the object.
Date User Action Args
2018-01-29 04:06:17njssetrecipients: + njs, giampaolo.rodola, asvetlov, yselivanov
2018-01-29 04:06:16njssetmessageid: <>
2018-01-29 04:06:16njslinkissue32703 messages
2018-01-29 04:06:16njscreate