[cfe] Report error on instantiation of enums from .dill

Closes #48350

Change-Id: I0cedf8a5a12e1a8dee546eec73e012519a054e13
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/232384
Reviewed-by: Chloe Stefantsova <cstefantsova@google.com>
Commit-Queue: Johnni Winther <johnniwinther@google.com>

pkg/front_end/lib/src/fasta/builder/type_declaration_builder.dart

@@ -28,6 +28,9 @@ abstract class TypeDeclarationBuilder implements ModifierBuilder {
   @override
   TypeDeclarationBuilder get origin;
 
+  /// Return `true` if this type declaration is an enum.
+  bool get isEnum;
+
   /// Creates the [DartType] corresponding to this declaration applied with
   /// [arguments] in [library] with the syntactical nullability defined by
   /// [nullabilityBuilder].
@@ -74,6 +77,9 @@ abstract class TypeDeclarationBuilderImpl extends ModifierBuilderImpl
   @override
   bool get isTypeDeclaration => true;
 
+  @override
+  bool get isEnum => false;
+
   @override
   String get fullNameForErrors => name;
 

pkg/front_end/lib/src/fasta/dill/dill_class_builder.dart

@@ -46,6 +46,9 @@ class DillClassBuilder extends ClassBuilderImpl {
             parent,
             cls.fileOffset);
 
+  @override
+  bool get isEnum => cls.isEnum;
+
   @override
   DillClassBuilder get origin => this;
 

pkg/front_end/lib/src/fasta/kernel/body_builder.dart

@@ -5371,7 +5371,7 @@ class BodyBuilder extends ScopeListener<JumpTarget>
       } else {
         target = b.member;
       }
-      if (type is SourceEnumBuilder &&
+      if (type.isEnum &&
           !(libraryBuilder.enableEnhancedEnumsInLibrary &&
               target is Procedure &&
               target.kind == ProcedureKind.Factory)) {

pkg/front_end/lib/src/fasta/source/source_enum_builder.dart

@@ -455,6 +455,9 @@ class SourceEnumBuilder extends SourceClassBuilder {
     return enumBuilder;
   }
 
+  @override
+  bool get isEnum => true;
+
   @override
   TypeBuilder? get mixedInTypeBuilder => null;
 

pkg/front_end/testcases/expression/instantiate_enum.expression.yaml

@@ -0,0 +1,9 @@
+# Copyright (c) 2022, the Dart project authors.  Please see the AUTHORS file
+# for details. All rights reserved. Use of this source code is governed by a
+# BSD-style license that can be found in the LICENSE file.
+
+entry_point: "main.dart"
+definitions: []
+position: "main.dart"
+expression: |
+  En(123, 'foo')

pkg/front_end/testcases/expression/instantiate_enum.expression.yaml.expect

@@ -0,0 +1,7 @@
+Errors: {
+  org-dartlang-debug:synthetic_debug_expression:1:1: Error: Enums can't be instantiated.
+  En(123, 'foo')
+  ^^
+}
+method /* from org-dartlang-debug:synthetic_debug_expression */ debugExpr() → dynamic
+  return invalid-expression "org-dartlang-debug:synthetic_debug_expression:1:1: Error: Enums can't be instantiated.\nEn(123, 'foo')\n^^";

pkg/front_end/testcases/expression/main.dart

@@ -127,3 +127,5 @@ void hasClosure() {
       .fold<int>(0, (previousValue, element) => previousValue + element.length);
   print("xCombinedLength = $xCombinedLength");
 }
+
+enum En { a, b, c }

pkg/front_end/testcases/general/instantiate_enum/main.dart

@@ -0,0 +1,18 @@
+// Copyright (c) 2022, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'main_lib.dart';
+
+enum Enum1 { a, b, c }
+
+typedef Alias1 = Enum1;
+
+test() {
+  Enum1(123, 'foo');
+  Enum2(123, 'foo');
+  Alias1(123, 'foo');
+  Alias2(123, 'foo');
+}
+
+main() {}

pkg/front_end/testcases/general/instantiate_enum/main.dart.textual_outline.expect

@@ -0,0 +1,6 @@
+import 'main_lib.dart';
+
+enum Enum1 { a, b, c }
+typedef Alias1 = Enum1;
+test() {}
+main() {}

pkg/front_end/testcases/general/instantiate_enum/main.dart.textual_outline_modelled.expect

@@ -0,0 +1,6 @@
+import 'main_lib.dart';
+
+enum Enum1 { a, b, c }
+main() {}
+test() {}
+typedef Alias1 = Enum1;

pkg/front_end/testcases/general/instantiate_enum/main.dart.weak.expect

@@ -0,0 +1,98 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:12:3: Error: Enums can't be instantiated.
+//   Enum1(123, 'foo');
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:13:3: Error: Enums can't be instantiated.
+//   Enum2(123, 'foo');
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:14:3: Error: Enums can't be instantiated.
+//   Alias1(123, 'foo');
+//   ^^^^^^
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:15:3: Error: Enums can't be instantiated.
+//   Alias2(123, 'foo');
+//   ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+typedef Alias1 = self::Enum1;
+class Enum1 extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Enum1> values = #C10;
+  static const field self::Enum1 a = #C3;
+  static const field self::Enum1 b = #C6;
+  static const field self::Enum1 c = #C9;
+  const constructor •(core::int index, core::String name) → self::Enum1
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "Enum1.${this.{core::_Enum::_name}{core::String}}";
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:12:3: Error: Enums can't be instantiated.
+  Enum1(123, 'foo');
+  ^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:13:3: Error: Enums can't be instantiated.
+  Enum2(123, 'foo');
+  ^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:14:3: Error: Enums can't be instantiated.
+  Alias1(123, 'foo');
+  ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:15:3: Error: Enums can't be instantiated.
+  Alias2(123, 'foo');
+  ^^^^^^";
+}
+static method main() → dynamic {}
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+typedef Alias2 = self2::Enum2;
+class Enum2 extends core::_Enum /*isEnum*/  {
+  static const field core::List<self2::Enum2> values = #C14;
+  static const field self2::Enum2 a = #C11;
+  static const field self2::Enum2 b = #C12;
+  static const field self2::Enum2 c = #C13;
+  const constructor •(core::int index, core::String name) → self2::Enum2
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "Enum2.${this.{core::_Enum::_name}{core::String}}";
+}
+
+constants  {
+  #C1 = 0
+  #C2 = "a"
+  #C3 = self::Enum1 {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "b"
+  #C6 = self::Enum1 {index:#C4, _name:#C5}
+  #C7 = 2
+  #C8 = "c"
+  #C9 = self::Enum1 {index:#C7, _name:#C8}
+  #C10 = <self::Enum1*>[#C3, #C6, #C9]
+  #C11 = self2::Enum2 {index:#C1, _name:#C2}
+  #C12 = self2::Enum2 {index:#C4, _name:#C5}
+  #C13 = self2::Enum2 {index:#C7, _name:#C8}
+  #C14 = <self2::Enum2*>[#C11, #C12, #C13]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main_lib.dart:
+- Enum2. (from org-dartlang-testcase:///main_lib.dart:5:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:103:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)
+
+org-dartlang-testcase:///main.dart:
+- Enum1. (from org-dartlang-testcase:///main.dart:7:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:103:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)

pkg/front_end/testcases/general/instantiate_enum/main.dart.weak.modular.expect

@@ -0,0 +1,72 @@
+library /*isNonNullableByDefault*/;
+//
+// Problems in library:
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:12:3: Error: Enums can't be instantiated.
+//   Enum1(123, 'foo');
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:13:3: Error: Enums can't be instantiated.
+//   Enum2(123, 'foo');
+//   ^^^^^
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:14:3: Error: Enums can't be instantiated.
+//   Alias1(123, 'foo');
+//   ^^^^^^
+//
+// pkg/front_end/testcases/general/instantiate_enum/main.dart:15:3: Error: Enums can't be instantiated.
+//   Alias2(123, 'foo');
+//   ^^^^^^
+//
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+typedef Alias1 = self::Enum1;
+class Enum1 extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Enum1> values = #C10;
+  static const field self::Enum1 a = #C3;
+  static const field self::Enum1 b = #C6;
+  static const field self::Enum1 c = #C9;
+  const constructor •(core::int index, core::String name) → self::Enum1
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "Enum1.${this.{core::_Enum::_name}{core::String}}";
+}
+static method test() → dynamic {
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:12:3: Error: Enums can't be instantiated.
+  Enum1(123, 'foo');
+  ^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:13:3: Error: Enums can't be instantiated.
+  Enum2(123, 'foo');
+  ^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:14:3: Error: Enums can't be instantiated.
+  Alias1(123, 'foo');
+  ^^^^^^";
+  invalid-expression "pkg/front_end/testcases/general/instantiate_enum/main.dart:15:3: Error: Enums can't be instantiated.
+  Alias2(123, 'foo');
+  ^^^^^^";
+}
+static method main() → dynamic {}
+
+constants  {
+  #C1 = 0
+  #C2 = "a"
+  #C3 = self::Enum1 {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "b"
+  #C6 = self::Enum1 {index:#C4, _name:#C5}
+  #C7 = 2
+  #C8 = "c"
+  #C9 = self::Enum1 {index:#C7, _name:#C8}
+  #C10 = <self::Enum1*>[#C3, #C6, #C9]
+}
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main.dart:
+- Enum1. (from org-dartlang-testcase:///main.dart:7:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:103:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)

pkg/front_end/testcases/general/instantiate_enum/main.dart.weak.outline.expect

@@ -0,0 +1,66 @@
+library /*isNonNullableByDefault*/;
+import self as self;
+import "dart:core" as core;
+
+import "org-dartlang-testcase:///main_lib.dart";
+
+typedef Alias1 = self::Enum1;
+class Enum1 extends core::_Enum /*isEnum*/  {
+  static const field core::List<self::Enum1> values = const <self::Enum1>[self::Enum1::a, self::Enum1::b, self::Enum1::c];
+  static const field self::Enum1 a = const self::Enum1::•(0, "a");
+  static const field self::Enum1 b = const self::Enum1::•(1, "b");
+  static const field self::Enum1 c = const self::Enum1::•(2, "c");
+  const constructor •(core::int index, core::String name) → self::Enum1
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "Enum1.${this.{core::_Enum::_name}{core::String}}";
+}
+static method test() → dynamic
+  ;
+static method main() → dynamic
+  ;
+
+library /*isNonNullableByDefault*/;
+import self as self2;
+import "dart:core" as core;
+
+typedef Alias2 = self2::Enum2;
+class Enum2 extends core::_Enum /*isEnum*/  {
+  static const field core::List<self2::Enum2> values = #C10;
+  static const field self2::Enum2 a = #C3;
+  static const field self2::Enum2 b = #C6;
+  static const field self2::Enum2 c = #C9;
+  const constructor •(core::int index, core::String name) → self2::Enum2
+    : super core::_Enum::•(index, name)
+    ;
+  method toString() → core::String
+    return "Enum2.${this.{core::_Enum::_name}{core::String}}";
+}
+
+constants  {
+  #C1 = 0
+  #C2 = "a"
+  #C3 = self2::Enum2 {index:#C1, _name:#C2}
+  #C4 = 1
+  #C5 = "b"
+  #C6 = self2::Enum2 {index:#C4, _name:#C5}
+  #C7 = 2
+  #C8 = "c"
+  #C9 = self2::Enum2 {index:#C7, _name:#C8}
+  #C10 = <self2::Enum2*>[#C3, #C6, #C9]
+}
+
+Extra constant evaluation status:
+Evaluated: ListLiteral @ org-dartlang-testcase:///main.dart:7:6 -> ListConstant(const <Enum1*>[const Enum1{_Enum.index: 0, _Enum._name: "a"}, const Enum1{_Enum.index: 1, _Enum._name: "b"}, const Enum1{_Enum.index: 2, _Enum._name: "c"}])
+Evaluated: ConstructorInvocation @ org-dartlang-testcase:///main.dart:7:14 -> InstanceConstant(const Enum1{_Enum.index: 0, _Enum._name: "a"})
+Evaluated: ConstructorInvocation @ org-dartlang-testcase:///main.dart:7:17 -> InstanceConstant(const Enum1{_Enum.index: 1, _Enum._name: "b"})
+Evaluated: ConstructorInvocation @ org-dartlang-testcase:///main.dart:7:20 -> InstanceConstant(const Enum1{_Enum.index: 2, _Enum._name: "c"})
+Extra constant evaluation: evaluated: 14, effectively constant: 4
+
+
+Constructor coverage from constants:
+org-dartlang-testcase:///main_lib.dart:
+- Enum2. (from org-dartlang-testcase:///main_lib.dart:5:6)
+- _Enum. (from org-dartlang-sdk:///sdk/lib/core/enum.dart:103:9)
+- Object. (from org-dartlang-sdk:///sdk/lib/core/object.dart:25:9)