Fix issue #1979: an unhandled exception in half open state must transition to closed and not prevent leaving half open state forever

[DominicUllmann]

Pull Request

The issue or feature being addressed

The Pull Request fixes the issue #1979 following the instructions discussed there.

Details on the issue fix or feature implementation

Before an unhandled exception lead to the circuit breaker being stuck forever in half open state. This fix allows the circuit breaker to transition from half open state to closed if a success result or an unhandled exception occurs.

Confirm the following

• I started this PR by branching from the head of the default branch
• I have targeted the PR to merge into the default branch
• I have included unit tests for the issue/feature
• I have successfully run a local build

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 83.64%. Comparing base (b8930cc) to head (99d26b0).
Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1991      +/-   ##
==========================================
- Coverage   83.64%   83.64%   -0.01%     
==========================================
  Files         312      312              
  Lines        7106     7105       -1     
  Branches     1056     1055       -1     
==========================================
- Hits         5944     5943       -1     
  Misses        789      789              
  Partials      373      373              

Flag	Coverage Δ
linux	83.64% <100.00%> (-0.01%)	⬇️
macos	83.64% <100.00%> (-0.01%)	⬇️
windows	?

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[DominicUllmann]

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[martincostello]

Thanks for the PR - the changes seem fine, but stryker seems to be unhappy about a lack of specificity in the tests as there is a failing mutant as the test is still passing if it intentionally breaks the test code.

[DominicUllmann]

Thanks for the PR - the changes seem fine, but stryker seems to be unhappy about a lack of specificity in the tests as there is a failing mutant as the test is still passing if it intentionally breaks the test code.

Thanks for the feedback. I had no time yesterday to have a look but will try to investigate why the change had this influence today and see how I can improve the tests.