[Enhanced enums] Strange compile error on CFE

[sgrekhov]

The folllowing co19 test fails https://github.com/dart-lang/co19/blob/master/LanguageFeatures/Enhanced-Enum/semantics_A09_t02.dart

enum E1 {
//   ^^
// [cfe] unspecified
  e1,
//^^
// [analyzer] unspecified
  e2,
  e3;

  final int e1 = 42;
//          ^^
// [cfe] unspecified
}

enum E2<T> {
//   ^^
// [cfe] unspecified
  e1<int>(42), // Fails here. Unexpected error at line 38, column 3: Constant evaluation error:
  e2<String>("42"),
//^^
// [analyzer] unspecified
  e3<bool>(false);

  const E2(T t);
  final List<E2> e2 = const [];
//               ^^
// [cfe] unspecified
}

enum E3 {
//   ^^
// [cfe] unspecified
  e1,
  e2,
  e3;

  static final int e1 = 42;
//                 ^^
// [analyzer] unspecified
}

main() {
  print(E1);
  print(E2);
  print(E3);
}

Why "Unexpected error at line 38, column 3: Constant evaluation error:" occurs. I don't see any errors on this line. To rerun the test use python3 tools/test.py -n cfe-strong-linux co19/LanguageFeatures/Enhanced-Enum/semantics_A09_t02

cc @eernstg

Tested on Dart SDK version: 2.17.0-edge.6bcc451e597867cb7c0b4f21d9143d0a43cbb401 (be) (Tue Feb 8 01:49:35 2022 +0000) on "linux_x64"

[eernstg]

Right, I couldn't see a reason for that error on line 38. Also I saw some 'Constant expression depends on itself' errors that I couldn't explain.

[chloestefantsova]

It seems to be an error triggered by the unhandled name conflict. I'm working on detecting and handling those conflicts, and it should fix this issue as well.