@Override
  public void accept(ISpecVisitor visitor) throws Exception {
    visitor.visitSpec(this);
    for (Field f : fields) f.accept(visitor);
    for (Method m : methods) m.accept(visitor);
    visitor.visitSpecAgain(this);
  }
AST node representing a Spock specification. In source
code, a Spec corresponds to one class definition extends from class Specification.

@author Peter Niederwieser
spock-core/src/main/java/org/spockframework/compiler/model/Spec.java