Do not run ExtractExplicitConstructorInvocationArguments on non-Java sources

[knutwannheden]

Running ExtractExplicitConstructorInvocationArguments over a corpus of open-source repositories throws on spring-cloud/spring-cloud-contract, in spring-cloud-contract-verifier/src/test/groovy/org/springframework/cloud/contract/verifier/util/SyntaxChecker.groovy:

java.lang.ClassCastException: class org.openrewrite.java.tree.J$FieldAccess cannot be cast to class org.openrewrite.java.tree.J$MethodInvocation
  org.openrewrite.java.internal.template.JavaTemplateParser.parseMethodArguments(JavaTemplateParser.java:223)
  org.openrewrite.java.internal.template.JavaTemplateJavaExtension$1.visitMethodInvocation(JavaTemplateJavaExtension.java:420)
  org.openrewrite.java.JavaTemplate.apply(JavaTemplate.java:196)
  org.openrewrite.java.migrate.lang.ExtractExplicitConstructorInvocationArguments$1$1.visitMethodInvocation(ExtractExplicitConstructorInvocationArguments.java:150)

How a Groovy file gets here

The visitor is a JavaIsoVisitor, whose isAcceptable takes any JavaSourceFile, and that includes G.CompilationUnit. The UsesJavaVersion<>(25) precondition does not narrow it either: the JavaVersion marker on a Groovy source carries the module's Java version, so it matches.

Groovy attributes a method type to super(..) only under @CompileStatic, taken from StaticTypesMarker.DIRECT_METHOD_CALL_TARGET. SyntaxChecker.groovy annotates its nested classes that way, so the getMethodType() == null bail-out does not catch them and the recipe builds a JavaTemplate whose stub, generated from the Groovy LST, is parsed as Java. JavaTemplateParser.parseMethodArguments then casts the result:

return (J.MethodInvocation) statementTemplateGenerator
        .listTemplatedTrees(cu, Statement.class).get(0);

For the two-argument super(URI.create(…), Kind.SOURCE) in that file the parse yields a J.FieldAccess. For a one-argument call the list comes back empty and the same line throws IndexOutOfBoundsException instead.

Fix

isAcceptable now returns sourceFile instanceof J.CompilationUnit. JEP 513 is a Java language feature and the transformation is written as a JavaTemplate, so Groovy and Kotlin are out of scope for this recipe whatever the LST happens to allow.

The cast in parseMethodArguments is unsound in general, but hardening it upstream would only trade one exception for another: a Java template applied to a non-Java LST has no correct result. The guard belongs at the recipe. Nothing about the shape is specific to this recipe, though — any JavaTemplate-based recipe without a source-file guard can reach the same line.

Tests

doNotRunOnGroovySources pins the guard with a minimal @CompileStatic Groovy source; without the fix it fails at JavaTemplateParser.java:223. The SimpleJavaFileObject subclass from SyntaxChecker.groovy reproduces the reported cast verbatim, but a two-line super(name.trim()) defends the same guard, so that is what the suite keeps.

• Note for whoever reads CI: on JDK 25 this test class already fails 12 of 18 on main, which is Preserve Java 25 constructor extraction statements #1206. This change adds no failures and its own test passes.