Extension type. Report EXTENSION_TYPE_WITH_ABSTRACT_MEMBER.

dart-lang/language@913b81e

Change-Id: Ic3303744ea4c1f2cc90df63a3ae52b51861757ca
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/322983
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

pkg/analysis_server/lib/src/services/correction/error_fix_status.yaml

@@ -673,6 +673,10 @@ CompileTimeErrorCode.EXTENSION_TYPE_INHERITED_MEMBER_CONFLICT:
   status: noFix
 CompileTimeErrorCode.EXTENSION_TYPE_REPRESENTATION_DEPENDS_ON_ITSELF:
   status: noFix
+CompileTimeErrorCode.EXTENSION_TYPE_WITH_ABSTRACT_MEMBER:
+  status: needsFix
+  notes: |-
+    Convert to block body.
 CompileTimeErrorCode.EXTERNAL_FIELD_CONSTRUCTOR_INITIALIZER:
   status: needsFix
   notes: |-

pkg/analyzer/lib/src/error/codes.g.dart

@@ -1705,6 +1705,16 @@ class CompileTimeErrorCode extends AnalyzerErrorCode {
     correctionMessage: "Try specifying a different type.",
   );
 
+  ///  Parameters:
+  ///  0: the name of the abstract method
+  ///  1: the name of the enclosing extension type
+  static const CompileTimeErrorCode EXTENSION_TYPE_WITH_ABSTRACT_MEMBER =
+      CompileTimeErrorCode(
+    'EXTENSION_TYPE_WITH_ABSTRACT_MEMBER',
+    "'{0}' must have a method body because '{1}' is an extension type.",
+    correctionMessage: "Try adding a body to '{0}'.",
+  );
+
   static const CompileTimeErrorCode EXTERNAL_FIELD_CONSTRUCTOR_INITIALIZER =
       CompileTimeErrorCode(
     'EXTERNAL_WITH_INITIALIZER',

pkg/analyzer/lib/src/error/error_code_values.g.dart

@@ -205,6 +205,7 @@ const List<ErrorCode> errorCodeValues = [
   CompileTimeErrorCode.EXTENSION_TYPE_IMPLEMENTS_REPRESENTATION_NOT_SUPERTYPE,
   CompileTimeErrorCode.EXTENSION_TYPE_INHERITED_MEMBER_CONFLICT,
   CompileTimeErrorCode.EXTENSION_TYPE_REPRESENTATION_DEPENDS_ON_ITSELF,
+  CompileTimeErrorCode.EXTENSION_TYPE_WITH_ABSTRACT_MEMBER,
   CompileTimeErrorCode.EXTERNAL_FIELD_CONSTRUCTOR_INITIALIZER,
   CompileTimeErrorCode.EXTERNAL_FIELD_INITIALIZER,
   CompileTimeErrorCode.EXTERNAL_VARIABLE_INITIALIZER,

pkg/analyzer/lib/src/generated/error_verifier.dart

@@ -718,6 +718,7 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
         node: node,
         element: element,
       );
+      _checkForExtensionTypeWithAbstractMember(node);
 
       super.visitExtensionTypeDeclaration(node);
     } finally {
@@ -2961,6 +2962,22 @@ class ErrorVerifier extends RecursiveAstVisitor<void>
     }
   }
 
+  void _checkForExtensionTypeWithAbstractMember(
+    ExtensionTypeDeclarationImpl node,
+  ) {
+    for (final member in node.members) {
+      if (member is MethodDeclarationImpl && !member.isStatic) {
+        if (member.isAbstract) {
+          errorReporter.reportErrorForNode(
+            CompileTimeErrorCode.EXTENSION_TYPE_WITH_ABSTRACT_MEMBER,
+            member,
+            [member.name.lexeme, node.name.lexeme],
+          );
+        }
+      }
+    }
+  }
+
   /// Verify that the given field formal [parameter] is in a constructor
   /// declaration.
   ///

pkg/analyzer/messages.yaml

@@ -5154,6 +5154,13 @@ CompileTimeErrorCode:
     problemMessage: "The extension type representation can't depend on itself."
     correctionMessage: Try specifying a different type.
     comment: No parameters.
+  EXTENSION_TYPE_WITH_ABSTRACT_MEMBER:
+    problemMessage: "'{0}' must have a method body because '{1}' is an extension type."
+    correctionMessage: "Try adding a body to '{0}'."
+    comment: |-
+      Parameters:
+      0: the name of the abstract method
+      1: the name of the enclosing extension type
   EXTERNAL_FIELD_CONSTRUCTOR_INITIALIZER:
     sharedName: EXTERNAL_WITH_INITIALIZER
     problemMessage: External fields can't have initializers.

pkg/analyzer/test/src/diagnostics/extension_type_with_abstract_member_test.dart

@@ -0,0 +1,102 @@
+// Copyright (c) 2023, 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 'package:analyzer/src/dart/error/syntactic_errors.dart';
+import 'package:analyzer/src/error/codes.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import '../dart/resolution/context_collection_resolution.dart';
+
+main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(ExtensionTypeWithAbstractMemberTest);
+  });
+}
+
+@reflectiveTest
+class ExtensionTypeWithAbstractMemberTest extends PubPackageResolutionTest {
+  test_getter() async {
+    await assertErrorsInCode('''
+extension type A(int it) {
+  int get foo;
+}
+''', [
+      error(CompileTimeErrorCode.EXTENSION_TYPE_WITH_ABSTRACT_MEMBER, 29, 12),
+    ]);
+  }
+
+  test_getter_external() async {
+    await assertNoErrorsInCode('''
+extension type A(int it) {
+  external int get foo;
+}
+''');
+  }
+
+  test_getter_static() async {
+    await assertErrorsInCode('''
+extension type A(int it) {
+  static int get foo;
+}
+''', [
+      error(ParserErrorCode.MISSING_FUNCTION_BODY, 47, 1),
+    ]);
+  }
+
+  test_method() async {
+    await assertErrorsInCode('''
+extension type A(int it) {
+  void foo();
+}
+''', [
+      error(CompileTimeErrorCode.EXTENSION_TYPE_WITH_ABSTRACT_MEMBER, 29, 11),
+    ]);
+  }
+
+  test_method_external() async {
+    await assertNoErrorsInCode('''
+extension type A(int it) {
+  external void foo();
+}
+''');
+  }
+
+  test_method_static() async {
+    await assertErrorsInCode('''
+extension type A(int it) {
+  static void foo();
+}
+''', [
+      error(ParserErrorCode.MISSING_FUNCTION_BODY, 46, 1),
+    ]);
+  }
+
+  test_setter() async {
+    await assertErrorsInCode('''
+extension type A(int it) {
+  set foo(int _);
+}
+''', [
+      error(CompileTimeErrorCode.EXTENSION_TYPE_WITH_ABSTRACT_MEMBER, 29, 15),
+    ]);
+  }
+
+  test_setter_external() async {
+    await assertNoErrorsInCode('''
+extension type A(int it) {
+  external set foo(int _);
+}
+''');
+  }
+
+  test_setter_static() async {
+    await assertErrorsInCode('''
+extension type A(int it) {
+  static set foo(int _);
+}
+''', [
+      error(ParserErrorCode.MISSING_FUNCTION_BODY, 50, 1),
+    ]);
+  }
+}

pkg/analyzer/test/src/diagnostics/test_all.dart

@@ -260,6 +260,8 @@ import 'extension_type_inherited_member_conflict_test.dart'
     as extension_type_inherited_member_conflict;
 import 'extension_type_representation_depends_on_itself_test.dart'
     as extension_type_representation_depends_on_itself;
+import 'extension_type_with_abstract_member_test.dart'
+    as extension_type_with_abstract_member;
 import 'external_field_constructor_initializer_test.dart'
     as external_field_constructor_initializer;
 import 'external_field_initializer_test.dart' as external_field_initializer;
@@ -1067,6 +1069,7 @@ main() {
     extension_type_implements_representation_not_supertype.main();
     extension_type_inherited_member_conflict.main();
     extension_type_representation_depends_on_itself.main();
+    extension_type_with_abstract_member.main();
     external_field_constructor_initializer.main();
     external_field_initializer.main();
     external_variable_initializer.main();