allow for roundtrips of cloudpaths through pickle serialization

[kujenga]

This avoids an exception thrown because the client is not serialized into the pickeld object, and thus when getstate is called the second time, there is no _client field to delete.

Closes #450

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• I have read and understood CONTRIBUTING.md
• Confirmed an issue exists for the PR, and the text Closes #issue appears in the PR summary (e.g., Closes #123).
• Confirmed PR is rebased onto the latest base
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[kujenga]

If there is an existing file this would be better suited to put it within let me know and happy to move it!

I verified that this does repro the issue without the above change.

[pjbull]

Separate file for serializing is fine. Can you also move this test over to the new file so they are together?

cloudpathlib/tests/test_cloudpath_file_io.py

Lines 457 to 472 in 08b018b

	def test_pickle(rig, tmpdir):
	p = rig.create_cloud_path("dir_0/file0_0.txt")
	with (tmpdir / "test.pkl").open("wb") as f:
	pickle.dump(p, f)
	with (tmpdir / "test.pkl").open("rb") as f:
	pickled = pickle.load(f)
	# test a call to the network
	assert pickled.exists()
	# check we unpickled, and that client is the default client
	assert str(pickled) == str(p)
	assert pickled.client == p.client
	assert rig.client_class._default_client == pickled.client

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.4%. Comparing base (08b018b) to head (514d447).
Report is 3 commits behind head on 454-local.

Additional details and impacted files

@@             Coverage Diff             @@
##           454-local    #454     +/-   ##
===========================================
- Coverage       93.7%   93.4%   -0.4%     
===========================================
  Files             23      23             
  Lines           1654    1655      +1     
===========================================
- Hits            1551    1546      -5     
- Misses           103     109      +6     

Files	Coverage Δ
cloudpathlib/cloudpath.py	93.5% <100.0%> (-0.4%)	⬇️

... and 2 files with indirect coverage changes

[pjbull]

Separate file for serializing is fine. Can you also move this test over to the new file so they are together?

cloudpathlib/tests/test_cloudpath_file_io.py

Lines 457 to 472 in 08b018b

	def test_pickle(rig, tmpdir):
	p = rig.create_cloud_path("dir_0/file0_0.txt")
	with (tmpdir / "test.pkl").open("wb") as f:
	pickle.dump(p, f)
	with (tmpdir / "test.pkl").open("rb") as f:
	pickled = pickle.load(f)
	# test a call to the network
	assert pickled.exists()
	# check we unpickled, and that client is the default client
	assert str(pickled) == str(p)
	assert pickled.client == p.client
	assert rig.client_class._default_client == pickled.client

[pjbull]

Looks good, thanks! One small ask to move the other pickle test to the same place

[pjbull]

@kujenga Planning a release soon—will you have a chance to wrap this PR?

[kujenga]

Thank you very much! Apologies I missed the earlier notification