Parallelize coverage analysis in CoveredTestResultPerTestMethod

[andre15silva]

Running the jacoco analyzer is an expensive operation.

Unfortunately, jacoco doesn't provide a way of doing an analysis of several executions at once, which is why test-runner needs to analyze them separately.

This PR introduces parallelism in that stage, moving analysis from the end of each test case to the end of the entire test suite and running it inside of a parallel stream.

Running flacoco with this modification on math70 on my PC (4 cores) reduced the execution time by around 40%.

[coveralls]

Pull Request Test Coverage Report for Build 1100800272

• 46 of 53 (86.79%) changed or added relevant lines in 11 files are covered.
• 5 unchanged lines in 4 files lost coverage.
• Overall coverage increased (+0.6%) to 45.401%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/main/java/eu/stamp_project/testrunner/listener/utils/ListenerUtils.java	8	9	88.89%
src/main/java/eu/stamp_project/testrunner/runner/coverage/JUnit5JacocoRunnerPerTestMethod.java	0	1	0.0%
src/main/java/eu/stamp_project/testrunner/listener/junit5/CoveragePerJUnit5TestMethod.java	0	5	0.0%

Files with Coverage Reduction	New Missed Lines	%
src/main/java/eu/stamp_project/testrunner/listener/impl/CoveragePerTestMethodImpl.java	1	84.0%
src/main/java/eu/stamp_project/testrunner/listener/junit5/CoveragePerJUnit5TestMethod.java	1	0%
src/main/java/eu/stamp_project/testrunner/runner/coverage/JUnit5JacocoRunnerPerTestMethod.java	1	0%
src/main/java/eu/stamp_project/testrunner/listener/impl/CoveredTestResultPerTestMethodImpl.java	2	73.75%

Totals
Change from base Build 1044521416:	0.6%
Covered Lines:	1086
Relevant Lines:	2392

---

💛 - Coveralls

[danglotb]

LGTM. Thank you very much!

Only the code duplication is a bit frustrating, but I do not see another way.

Could we put the following code:

// We need to clone each result so it doesn't get changed by the runtime afterwards
ExecutionDataStore executionDataStore = new ExecutionDataStore();
			this.internalCoveredTestResult.getExecutionData().getContents().stream().forEach(x -> {
	ExecutionData executionData = new ExecutionData(x.getId(), x.getName(), x.getProbes().clone());
	synchronized (executionDataStore) {
		executionDataStore.put(executionData);
	}
});
this.internalCoveredTestResult.getExecutionDataStoreMap().put(
	this.toString.apply(testIdentifier),
	executionDataStore
);

In a "Utils" class, in order to avoid the duplication? Like something:

public static void cloneAndAddExecutionDataStore(CoveredTestResultPerTestMethod internalCoveredTestResult, Function<Description, String) toString) {
	// We need to clone each result so it doesn't get changed by the runtime afterwards
	ExecutionDataStore executionDataStore = new ExecutionDataStore();
	internalCoveredTestResult.getExecutionData().getContents().stream().forEach(x -> {
		ExecutionData executionData = new ExecutionData(x.getId(), x.getName(), x.getProbes().clone());
		synchronized (executionDataStore) {
			executionDataStore.put(executionData);
		}
	});
	internalCoveredTestResult.getExecutionDataStoreMap().put(
		toString.apply(description),
		executionDataStore
	);
}

[andre15silva]

Hi @danglotb ,

Yes, for sure. I moved the cloning into an Utils class, but not the insertion since they are different implementation classes.