Progress eclipse cleanup

[blacelle]

This revives the interest in Eclipse JDT CleanUp.

1. The implementation is rooted in main...issue_292, but I would pursue the work in a forked repository.
2. This is concurrent to my work in CleanThat, integrating various refactoring/cleanups engines (Progress with Eclipse CleanUp as Refactorer solven-eu/cleanthat#423)
3. Merging would probably waits the rework of Eclipse integration in Spotless Use Equo Solstice to calculate and download eclipse dependencies #1524
4. This is a direct answer to Add support for Eclipse Clean Up #292
5. Unittests in _ext/eclipse-jdt are not available to myself from Intellij (they are grayed, like in case of classpath issue, hence not detected as source/unitTests). Is there a tips to get them working? (IntelliJ)
   

I resynced the branch with Spotless main.

[blacelle]

@nedtwigg I had issues making it running in Cleanthat. Given the boilterplates around Eclipse integration, I feel preferable to drop Eclipse Cleanup from CleanThat, and get Cleanthat relying on Spotless.

As it stands, this PR holds core integration, but not availability through build options (Gradle, Maven, etc).

Do you prefer I open a separate PR for build-systems integrations ? (I will start with Eclipse). Or is it OK/preferable to have the whole thing in a single PR?

[nedtwigg]

Single PR is fine.

[blacelle]

This would help #1379 (comment)

[blacelle]

Unittests in _ext/eclipse-jdt are not available to myself from Intellij (they are grayed, like in case of classpath issue, hence not detected as source/unitTests). Is there a tips to get them working? (IntelliJ)

Any idea @nedtwigg ?

[nedtwigg]

That whole project structure is about to be nuked. Everything in the _ext is becoming just a plain old sourceSet of lib-extra in #1524 which I will merge later today.

[blacelle]

@nedtwigg This was in the old eclipse-jdt build.gradle. I suppose it has to be converted into things like:

public static EquoBasedStepBuilder createBuilder(Provisioner provisioner) {
	return new EquoBasedStepBuilder(NAME, provisioner, EclipseJdtCleanUpStep::apply) {
		@Override
		protected P2Model model(String version) {
			var model = new P2Model();
			addPlatformRepo(model, version);
			model.getInstall().add("org.eclipse.jdt.core");
			return model;
		}

[nedtwigg]

That is correct.

[blacelle]

I need to check the migration of EclipseJdtFormatterStepImpl to see how this was migrated.

[nedtwigg]

This SpotlessEclipseFramework stuff is tricky. Depending on what version of Eclipse, and what methods you are calling, it might not matter if any of the OSGi stuff has been initialized at all. Or you might need all of it initialized.

For the current Eclipse JDT and CDT formatters, nothing is initialized at all, and that works fine. For Groovy we needed to start the full Solstice OSGi thing. If you are getting NPE or "blah not initialized" errors, I would copy this into your static initializer as a template.

spotless/lib-extra/src/groovy/java/com/diffplug/spotless/extra/glue/groovy/GrEclipseFormatterStepImpl.java

Lines 52 to 70 in bc21f83

	public class GrEclipseFormatterStepImpl {
	static {
	NestedJars.setToWarnOnly();
	NestedJars.onClassPath().confirmAllNestedJarsArePresentOnClasspath(CacheLocations.nestedJars());
	try {
	var solstice = Solstice.findBundlesOnClasspath();
	solstice.warnAndModifyManifestsToFix();
	var props = Map.of("osgi.nl", "en_US",
	Constants.FRAMEWORK_STORAGE_CLEAN, Constants.FRAMEWORK_STORAGE_CLEAN_ONFIRSTINIT,
	EquinoxLocations.PROP_INSTANCE_AREA, Files.createTempDirectory("spotless-groovy").toAbsolutePath().toString());
	solstice.openShim(props);
	ShimIdeBootstrapServices.apply(props, solstice.getContext());
	solstice.start("org.apache.felix.scr");
	solstice.startAllWithLazy(false);
	solstice.start("org.codehaus.groovy.eclipse.core");
	} catch (IOException e) {
	throw new RuntimeException(e);
	}
	}

[blacelle]

Thanks for the insights. For now, I'm feeling a bit overwhelmed here. I'll take some time to get through it.

[blacelle]

JavaCore is unknown here, while it is known in the jdt.compile module. How should I manage additional dependencies in test classes in lib-extra?

[blacelle]

@nedtwigg I would need a hint here.

[nedtwigg]

The build does not currently have a way to run tests against the Eclipse classpath. We would have to add something into this block

spotless/lib-extra/build.gradle

Lines 47 to 56 in bc21f83

	for (needsP2 in NEEDS_P2_DEPS) {
	sourceSets.register(needsP2) {
	compileClasspath += sourceSets.main.output
	runtimeClasspath += sourceSets.main.output
	java {}
	}
	dependencies {
	add("${needsP2}CompileOnly", "dev.equo.ide:solstice:${VER_SOLSTICE}")
	}
	}

Along these lines

tasks.register("${needsP2}Test", Test) {
  // setup classpath somehow
}
...

into 'jdtCompileOnly', { ... }
into 'jdtTestImplementation', { ... }

There would be some copy pasting going on, if this got implemented then there'd be no copy-pasting necessary

• p2deps plugin put jars into multiple source sets equodev/equo-ide#109

[blacelle]

This is still quite a long way to go.

1. Enable customization/selection of CleanUp rules
2. Migration to updated Eclipse. (e.g. around Indexer.getInstance().enableAutomaticIndexing(false);)
3. There was no unitTest in the initial work for cleanup (but there was for organizeImports). Hence, I'm not confident the minimal work was working fine.