Introduce declarative timeouts

[marcphilipp]

This PR introduces declarative timeouts for testable and lifecycle methods. The API surface consists of a new @Timeout implementation that can be applied to @Test, @TestTemplate, @TestFactory, and lifecycle methods. In addition, it can be applied to a test class which has the same meaning as declaring it on all of its testable, but not its lifecycle methods.

Moreover, default timeouts can be defined using configuration parameters for all of the above methods, all lifecycle methods, all testable methods, or each type individually.

The timeout is implemented in a preemptive manner, but without having to execute the test in a different thread. Instead, a single-thread ExecutorService is used to schedule interrupting the original test thread. This way, ThreadLocal will continue to work which is important for integration tests that use frameworks like Spring and its @Transactional support.

Resolves #80.

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Definition of Done

• There are no TODOs left in the code
• Method preconditions are checked and documented in the method's Javadoc
• Coding conventions (e.g. for logging) have been followed
• Change is covered by automated tests including corner cases, errors, and exception handling
• Public API has Javadoc and @API annotations
• Change is documented in the User Guide and Release Notes
• All continuous integration builds pass

[codecov]

Codecov Report

Merging #1885 into master will increase coverage by 0.16%.
The diff coverage is 96.12%.

@@             Coverage Diff              @@
##             master    #1885      +/-   ##
============================================
+ Coverage     91.42%   91.58%   +0.16%     
- Complexity     4149     4225      +76     
============================================
  Files           351      356       +5     
  Lines          9978    10133     +155     
  Branches        802      814      +12     
============================================
+ Hits           9122     9280     +158     
+ Misses          659      654       -5     
- Partials        197      199       +2

Impacted Files	Coverage Δ	Complexity Δ
...it/jupiter/engine/extension/ExtensionRegistry.java	94.44% <ø> (ø)	24 <0> (ø)	⬇️
...it/jupiter/engine/extension/TimeoutInvocation.java	100% <100%> (ø)	7 <7> (?)
...jupiter/engine/extension/TimeoutConfiguration.java	100% <100%> (ø)	17 <17> (?)
...upiter/engine/extension/TimeoutDurationParser.java	100% <100%> (ø)	5 <5> (?)
...unit/jupiter/engine/extension/TimeoutDuration.java	89.47% <89.47%> (ø)	14 <14> (?)
...nit/jupiter/engine/extension/TimeoutExtension.java	93.1% <93.1%> (ø)	27 <27> (?)
... and 5 more

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[sbrannen]

First pass at a review. Haven't reviewed the extension implementation or tests in detail yet.

[jbduncan]

@marcphilipp Have you considered using EqualsVerifier here? :)

[jbduncan]

ping :)

[sbrannen]

This is coming along very nicely. Great work!

I've requested a few minor changes.

[sbrannen]

Thanks for the previous round of updates!

Hopefully this is my final set of review comments and questions.