Copying property objects results in a TypeError. Steps to reproduce:
```
>>> import copy
>>> obj = property()
>>> copy.copy(obj)
````
This affects both shallow and deep copying.
My idea for a fix is to add property objects to the list of "atomic" objects in the copy module.
These already include types like functions and type objects.
I also added property objects to the unit tests test_copy_atomic and test_deepcopy_atomic. This is my first PR, and it's highly likely I've made some mistake, so please be kind :)
https://bugs.python.org/issue38293
Motivation for this PR (comment from @vstinner in bpo issue):
```
Warning seen o AMD64 Ubuntu Shared 3.x buildbot:
https://buildbot.python.org/all/#/builders/141/builds/2593
test_devnull_output (test.test_a=syncio.test_subprocess.SubprocessThreadedWatcherTests) ...
Warning -- threading_cleanup() failed to cleanup 1 threads (count: 1, dangling: 2)
```
The following implementation details for the new method are TBD:
1) Public vs private
2) Inclusion in `close()`
3) Name
4) Coroutine vs subroutine method
5) *timeout* parameter
If it's a private method, 3, 4, and 5 are significantly less important.
I started with the most minimal implementation that fixes the dangling threads without modifying the regression tests, which I think is particularly important. I typically try to avoid directly modifying existing tests as much as possible unless it's necessary to do so. However, I am open to changing any part of this.
https://bugs.python.org/issue38356
Although the underlying libffi issue remains open, adding these
checks have caused problems in third-party projects which are in
widespread use. See the issue for examples.
The corresponding tests have also been skipped.
nntplib.NNTP and nntplib.NNTP_SSL now raise a ValueError
if the given timeout for their constructor is zero to
prevent the creation of a non-blocking socket.
poplib.POP3 and poplib.POP3_SSL now raise a ValueError
if the given timeout for their constructor is zero to
prevent the creation of a non-blocking socket.
* Add test cases for dataclasses.
* Add test for repr output of field.
* Add test for ValueError to be raised when both default and default_factory are passed.
imaplib.IMAP4 and imaplib.IMAP4_SSL now have an
optional *timeout* parameter for their constructors.
Also, the imaplib.IMAP4.open() method now has an optional *timeout* parameter
with this change. The overridden methods of imaplib.IMAP4_SSL and
imaplib.IMAP4_stream were applied to this change.
When producing the bytecode of exception handlers with name binding (like `except Exception as e`) we need to produce a try-finally block to make sure that the name is deleted after the handler is executed to prevent cycles in the stack frame objects. The bytecode associated with this try-finally block does not have source lines associated and it was causing problems when the tracing functionality was running over it.
This uses the heuristic of assuming a named tuple is a subclass of
tuple with a _fields attribute. This change means that contents of
a named tuple wouldn't be converted - if a user wants to have
ConvertingTuple functionality from a namedtuple, they will have to
implement it themselves.
Ram Rachum
Guðni Natan Gunnarsson
Kyle Stanley
Vinay Sajip
Victor Stinner
Dong-hee Na
Jason R. Coombs
Karthikeyan Singaravelan
Pablo Galindo
Serhiy Storchaka
Daniel Hahler
Steve Dower
An Long
Derek Brown
Andrew Svetlov
Tal Einat
Anthony Sottile
Terry Jan Reedy
Raymond Hettinger
Batuhan Taşkaya
Jendrik Seipp
Ned Batchelder
Zackery Spytz
Mark Shannon