[New-bugs-announce] [issue41752] Wave shouldn't try to close an open file at all costs

[Karel]

New submission from Karel <biosthezerg at centrum.cz>:

The standard `wave` library tries to close a file unconditionally. I believe this is wrong.

>From the docs:
Wave_write.close(): Make sure nframes is correct, and close the file if it was opened by wave. *This method is called upon object collection.* [...]

This leads to problems when an exception is throw when a file is open. See the following MWE:
```
from io import BytesIO
import wave
audio_out = BytesIO() 
with wave.open(audio_out, "w") as file_out:
    raise Exception('aaa!') 

Error: # channels not specified
```

Even when I remove the context manager, so it shouldn't close the file automatically, it still does, the following:
```
file_out = wave.open(audio_out, "w")
raise Exception('aaa!')
```
doesn't throw an error at me immediately, but when the file_out variable is running out of scope, I get a printout saying: `Exception ignored in: <bound method Wave_write.__del__ of <wave.Wave_write object at 0x7ff549064eb8>> [...] wave.Error: # channels not specified`.

Expected behaviour: When I use a Wave_write object as a context manager, it tries to close the file unconditionally (as it does now). When I call `wave.open` manually, no automatic file closing is done.

----------
components: Library (Lib)
messages: 376634
nosy: biosthezerg
priority: normal
severity: normal
status: open
title: Wave shouldn't try to close an open file at all costs
type: behavior
versions: Python 3.7

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue41752>
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