Introduce InvocationInterceptor extension API

[marcphilipp]

Overview

The new extension API allows intercepting the invocation of test class
constructors, lifecycle methods, testable methods, and dynamic tests.
It validates that an invocation is asked to proceed exactly once. The
user guide is updated with an example that executes all test methods in
Swing's EDT.

Resolves #157.

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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

[sbrannen]

Thanks for working on this and submitting the PR!

I think this is coming along very nicely.

I haven't reviewed it yet in an IDE, so my comments here are based solely on what I can see in the browser.

[marcphilipp]

FYI The JaCoCo issue was caused by InvocationInterceptor being the first Extension interface with default methods.

[sbrannen]

FYI The JaCoCo issue was caused by InvocationInterceptor being the first Extension interface with default methods.

Ahhhh.... nice detective work!

And... I saw your commit to fix it... exactly like I'd have done. 😉

So glad they added Predicate.negate() in Java 11.

[sbrannen]

But... wait!

Didn't TestWatcher originally have default methods?

Speaking of that, @junit-team/junit-lambda, why does TestWatcher not have empty default methods? 🤔

[marcphilipp]

I was wondering that, too. It looks like it had default methods in the initial proposal but they were removed later in the PR.

[marcphilipp]

@geo-m Do you remember?

[sbrannen]

I was wondering that, too. It looks like it had default methods in the initial proposal but they were removed later in the PR.

That would explain why the same JaCoCo problem appeared and then magically disappeared back then.

In any case, I think we should make those methods default methods again.

I realize I'm hijacking this PR on this topic now, but...

@junit-team/junit-lambda, any objections to making that change?

[marcphilipp]

None from me.

[sbrannen]

None from me.

Good, 'cause I've already made the change on my machine. 😇

[codecov]

Codecov Report

Merging #1852 into master will decrease coverage by 0.14%.
The diff coverage is 79.71%.

@@             Coverage Diff              @@
##             master    #1852      +/-   ##
============================================
- Coverage     91.55%   91.41%   -0.15%     
- Complexity     4097     4119      +22     
============================================
  Files           344      348       +4     
  Lines          9773     9876     +103     
  Branches        798      801       +3     
============================================
+ Hits           8948     9028      +80     
- Misses          630      651      +21     
- Partials        195      197       +2

Impacted Files	Coverage Δ	Complexity Δ
...piter/engine/descriptor/JupiterTestDescriptor.java	89.28% <ø> (+0.76%)	23 <0> (-1)	⬇️
...t/jupiter/api/extension/InvocationInterceptor.java	0% <0%> (ø)	0 <0> (?)
...r/engine/descriptor/TestFactoryTestDescriptor.java	94.73% <100%> (+0.09%)	20 <1> (ø)	⬇️
...it/jupiter/engine/execution/ExecutableInvoker.java	94.28% <100%> (+3.37%)	21 <4> (+1)	⬆️
...nit/jupiter/engine/execution/MethodInvocation.java	100% <100%> (ø)	6 <6> (?)
...scriptor/TestTemplateInvocationTestDescriptor.java	100% <100%> (ø)	7 <2> (+1)	⬆️
...er/engine/descriptor/TestMethodTestDescriptor.java	96.94% <100%> (+0.07%)	43 <0> (ø)	⬇️
...r/engine/descriptor/DynamicTestTestDescriptor.java	100% <100%> (ø)	6 <4> (+3)	⬆️
...r/engine/descriptor/DynamicNodeTestDescriptor.java	100% <100%> (ø)	4 <1> (ø)	⬇️
...ter/engine/descriptor/DynamicExtensionContext.java	33.33% <33.33%> (ø)	2 <2> (?)
... and 11 more

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