Error when reaches a constructor on an enum

[bdlukaa]

When the parser reaches a constructor on an enum, an error is thrown.

---

The following enum, for example, is enough to stop the parser from parsing.

enum ButtonState {
  up,
  upAndSelected,
  down,
  downAndSelected,
  hover,
  hoverAndSelected,
  disabled,
  disabledAndSelected;

  const ButtonState();

}

type 'EnumDeclarationImpl' is not a subtype of type 'ClassDeclaration' in type cast
#0      serializeConstructorDeclaration (package:dartdoc_json/src/constructor_declaration.dart:16:42)
#1      serializeMemberList (package:dartdoc_json/src/member_list.dart:18:14)
#2      serializeEnumDeclaration (package:dartdoc_json/src/enum_declaration.dart:30:16)
#3      serializeCompilationUnit (package:dartdoc_json/src/compilation_unit.dart:25:20)

The code assumes that the parent of the constructor is a class, but it is not the case. Recently, in dart, it was added more features to enums.

Additional resources:

• https://github.com/flame-engine/flame/blob/main/packages/flame/lib/src/components/input/advanced_button_component.dart