class A extends {}
-----
Groovy script
  Class definition
    Modifiers
      <empty list>
    PsiElement(class)('class')
    PsiWhiteSpace(' ')
    PsiElement(identifier)('A')
    PsiWhiteSpace(' ')
    Extends clause
      PsiElement(extends)('extends')
      PsiErrorElement:Identifier expected
        <empty list>
    Implements clause
      <empty list>
    PsiWhiteSpace(' ')
    Type definition body
      PsiElement({)('{')
      PsiElement(})('}')