Groovy Closure not checking owner or delegate scope

Question

I am writing a small Groovy DSL , which relies on Groovy Closures . I then run the DSL from a Java program by using GroovyShell and a DelegatingScript .

Code invoking the script from Java:

DelScript project = new DelScript ();

CompilerConfiguration cc = new CompilerConfiguration();
cc.setScriptBaseClass("groovy.util.DelegatingScript");
GroovyShell sh = new GroovyShell(Launcher.class.getClassLoader(), new Binding(), cc);

DelegatingScript script = (DelegatingScript) sh.parse(new File(path));
script.setDelegate(project);
script.run();

The instance of DelScript works as the this reference inside the script, eg any member or method not found in the script itself is searched in the instance of DelScript .

My script can include the following expressions:

create (name: "test") {
    // this code can be used to initialize the 
    // object that is created here
    testProperty = "I'm an example"
}

The intention of this code is to create an object and then call the closure, which can be used to initialize it. As I said before, the create method resides in the DelScript instance, (which is what I want) and it looks like this:

def create(arguments, configClosure) {
    // create new object
    def x = new Impl(arguments)

    // use configClosure to init it
    configClosure.delegate = x
    configClosure()
}

Although I set the delegate of the configClosure , I get an error that testProperty is not a part of DelScript . I know that the DelScript instance is the this of the configClosure , since I created it in the DelScript scope, but I thought that the closure would check references in the order: this -> owner -> delegate . It never checks delegate in my case but raises an exception right after checking this .

Can anyone give me some feedback on what I am doing wrong?

Answer 1

After the line

configClosure.delegate = x

Put

configClosure.resolveStrategy = Closure.DELEGATE_FIRST