Add unit test showing null Methodinvocation type

[greg-dennis]

What's changed?

What's your motivation?

Add unit test showing null Methodinvocation type. This test fails in this repo but the very same test passes when added to the rewrite repo.

Anything in particular you'd like reviewers to focus on?

Anyone you would like to review specifically?

Have you considered any alternatives or workarounds?

Any additional context

Checklist

• I've added unit tests to cover both positive and negative cases
• I've read and applied the recipe conventions and best practices
• I've used the IntelliJ IDEA auto-formatter on affected files

[Laurens-W]

Suggested change

	@Test
	void showNullMethodInvocationType() {
	//language=kotlin
	SourceSpec<?> source = getOnly(
	kotlin(
	"""
	class ExampleTest {
	fun myTest() = run {
	return 1
	}
	}
	"""
	));
	Parser parser = KotlinParser.builder().build();
	Path sourcePath = parser.sourcePathFromSourceText(source.getDir(), source.getBefore());
	ExecutionContext ctx = new InMemoryExecutionContext();
	Parser.Input input = Parser.Input.fromString(
	sourcePath, source.getBefore(), parser.getCharset(ctx));
	SourceFile sourceFile = getOnly(
	parser.parseInputs(singleton(input), null, ctx).toList());
	new FindMissingTypesVisitor().visit(sourceFile, ctx);
	}
	private static class FindMissingTypesVisitor extends KotlinIsoVisitor<ExecutionContext> {
	@Override
	public J.MethodInvocation visitMethodInvocation(J.MethodInvocation method,
	ExecutionContext ctx) {
	assertNotNull(method.getMethodType());
	return method;
	}
	}
	private static <T> T getOnly(Iterable<T> iterable) {
	Iterator<T> iter = iterable.iterator();
	T only = iter.next();
	assertFalse(iter.hasNext());
	return only;
	}
	@Override
	public void defaults(RecipeSpec spec) {
	spec
	.parser(KotlinParser.builder());
	}
	@Test
	void showNullMethodInvocationType() {
	rewriteRun(
	//language=kotlin
	kotlin(
	"""
	class ExampleTest {
	fun myTest() = run {
	return 1
	}
	}
	"""
	));
	}

I've simplified it to this and am indeed seeing it fail in rewrite-testing-frameworks but succeed in rewrite

[greg-dennis]

Right, that simple example will show the symptom, but I found the failure to be more cryptic. The intention of the PR was to reveal the underlying issue: that the type of the run method invocation is null.

[greg-dennis]

@Laurens-W, there appears to be other code that "expects" the types of Kotlin method invocations to sometimes be null (example). If that is sometimes "expected" behavior, the following workaround might make sense: openrewrite/rewrite#6409

Thoughts?