Improved TestStep creation performance

[jkronegg]

🤔 What's changed?

Refactored TestAbortedExceptions Predicate creation.

⚡️ What's your motivation?

Performance gain (Predicate creation is about 50'000 times faster).
Fixes #2666

🏷️ What kind of change is this?

• 🏦 Refactoring/debt/DX (improvement to code design, tooling, documentation etc. without changing behaviour)

♻️ Anything particular you want feedback on?

Nothing.

📋 Checklist:

• I agree to respect and uphold the Cucumber Community Code of Conduct
• I've changed the behaviour of the code
  • I have added/updated tests to cover my changes.
• My change requires a change to the documentation.
  • I have updated the documentation accordingly.
• Users should know about my change
  • I have added an entry to the "Unreleased" section of the CHANGELOG, linking to this pull request.

[mpkorstanje]

Would a for loop be faster?

[jkronegg]

I benchmarked the following code:

static Predicate<Throwable> createIsTestAbortedExceptionPredicate7() {
    ClassLoader defaultClassLoader = ClassLoaders.getDefaultClassLoader();
    return throwable -> {
        for (String s : TEST_ABORTED_EXCEPTIONS) {
            try {
                Class<?> aClass = defaultClassLoader.loadClass(s);
                if (aClass.isInstance(throwable)) {
                    return true;
                }
            } catch (Throwable t) {
                rethrowIfUnrecoverable(t);
                log.debug(t,
                        () -> String.format(
                                "Failed to load class %s: will not be supported for aborted executions.", s));
            }
        }
        return false;
    };
}

The JMH benchmark says the variant 7 (the one with a loop) is slightly slower than the proposed version (variant 6), but not significantly :

Benchmark                                                               Mode  Cnt          Score          Error  Units
TestAbortedExceptionsBenchmark.createIsTestAbortedExceptionPredicate5  thrpt   25  264824252,996 ± 4775342,657  ops/s
TestAbortedExceptionsBenchmark.createIsTestAbortedExceptionPredicate6  thrpt   25  259886661,320 ±  1766902,768  ops/s
TestAbortedExceptionsBenchmark.createIsTestAbortedExceptionPredicate7  thrpt   25  254627500,665 ± 12269987,245  ops/s

I think the code readability is better with the Stream+anyMatch than with the loop, so I would prefer to keep the proposed version..

[mpkorstanje]

If you run mvn clean install it will run all tests and fix the formatting.

[codecov]

Codecov Report

Merging #2667 (9900d2d) into main (e32379e) will decrease coverage by 0.00%.
The diff coverage is 80.00%.

❗ Current head 9900d2d differs from pull request most recent head 42cd2a6. Consider uploading reports for the commit 42cd2a6 to get more accurate results

@@             Coverage Diff              @@
##               main    #2667      +/-   ##
============================================
- Coverage     84.82%   84.82%   -0.01%     
+ Complexity     2695     2694       -1     
============================================
  Files           322      322              
  Lines          9576     9574       -2     
  Branches        907      907              
============================================
- Hits           8123     8121       -2     
  Misses         1121     1121              
  Partials        332      332              

Impacted Files	Coverage Δ
...io/cucumber/core/runner/TestAbortedExceptions.java	91.66% <80.00%> (-1.20%)	⬇️

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[aslakhellesoy]

Hi @jkronegg,

Thanks for your making your first contribution to Cucumber, and welcome to the Cucumber committers team! You can now push directly to this repo and all other repos under the cucumber organization! 🍾

In return for this generous offer we hope you will:

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On behalf of the Cucumber core team,
Aslak Hellesøy
Creator of Cucumber

[mpkorstanje]

Cheers!