fix: use native exists() method in GSClient

[bachya]

SSIA

Closes #356

---

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[pjbull]

Thanks @bachya!

One change here. Can you also confirm that you tested the case in #356 with a totally empty bucket and this method works?

[bachya]

@pjbull Confirmed, I have this working on an empty GCP bucket.

[pjbull]

Thanks @bachya, happy to merge this once the code quality and mocked tests are passing.

[pjbull]

Tests need an update in the mocked version (which mock the cloud SDKs):

• Update MockBucket to have exists method.
• Should be implemented like the Azure backend to just be true for the test.

More info on running the test suite here: https://cloudpathlib.drivendata.org/stable/contributing/#tests

[bachya]

Thanks, @pjbull. I couldn't see the results until you approved the CI run; got them now, and I'll update the tests.

[pjbull]

@bachya just fyi, you can run make lint and make test locally so you don't have to wait for the CI runs.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.4%. Comparing base (c9da3f3) to head (3e16d8f).

Additional details and impacted files

@@           Coverage Diff            @@
##           master    #420     +/-   ##
========================================
- Coverage    93.8%   93.4%   -0.4%     
========================================
  Files          23      23             
  Lines        1644    1639      -5     
========================================
- Hits         1543    1532     -11     
- Misses        101     107      +6     

Files	Coverage Δ
cloudpathlib/gs/gsclient.py	91.4% <100.0%> (-1.7%)	⬇️

... and 2 files with indirect coverage changes

[pjbull]

Looks good! I'm going to merge into a repo-local branch so we can run against the live server backends, which is not possible on PRs from forks.