Issue 54485. Report error when external constructor has a field formal parameter.

Bug: https://github.com/dart-lang/sdk/issues/54485
Change-Id: Id2cec10b1c8bdb7bba5d608f28a3b55b8f4146ad
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/344180
Reviewed-by: Kallen Tu <kallentu@google.com>
Reviewed-by: Chloe Stefantsova <cstefantsova@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

pkg/_fe_analyzer_shared/lib/src/messages/codes_generated.dart

@@ -4628,7 +4628,7 @@ const Code<Null> codeExternalConstructorWithFieldInitializers =
 // DO NOT EDIT. THIS FILE IS GENERATED. SEE TOP OF FILE.
 const MessageCode messageExternalConstructorWithFieldInitializers =
     const MessageCode("ExternalConstructorWithFieldInitializers",
-        analyzerCodes: <String>["EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS"],
+        index: 178,
         problemMessage: r"""An external constructor can't initialize fields.""",
         correctionMessage:
             r"""Try removing the field initializers, or removing the keyword 'external'.""");

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

@@ -2800,6 +2800,10 @@ ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_BODY:
   status: needsFix
   notes: |-
     Remove the `external` keyword.
+ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS:
+  status: needsFix
+  notes: |-
+    Remove the `external` keyword or remove the initializers.
 ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_INITIALIZER:
   status: needsFix
   notes: |-

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

@@ -199,6 +199,7 @@ final fastaAnalyzerErrorCodes = <ErrorCode?>[
   ParserErrorCode.EXTRANEOUS_MODIFIER_IN_PRIMARY_CONSTRUCTOR,
   ParserErrorCode.ABSTRACT_FINAL_BASE_CLASS,
   ParserErrorCode.ABSTRACT_FINAL_INTERFACE_CLASS,
+  ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS,
 ];
 
 class ParserErrorCode extends ErrorCode {
@@ -817,6 +818,15 @@ class ParserErrorCode extends ErrorCode {
         "'external'.",
   );
 
+  static const ParserErrorCode EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS =
+      ParserErrorCode(
+    'EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS',
+    "An external constructor can't initialize fields.",
+    correctionMessage:
+        "Try removing the field initializers, or removing the keyword "
+        "'external'.",
+  );
+
   static const ParserErrorCode EXTERNAL_CONSTRUCTOR_WITH_INITIALIZER =
       ParserErrorCode(
     'EXTERNAL_CONSTRUCTOR_WITH_INITIALIZER',

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

@@ -735,6 +735,7 @@ const List<ErrorCode> errorCodeValues = [
   ParserErrorCode.EXTENSION_TYPE_WITH,
   ParserErrorCode.EXTERNAL_CLASS,
   ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_BODY,
+  ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS,
   ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_INITIALIZER,
   ParserErrorCode.EXTERNAL_ENUM,
   ParserErrorCode.EXTERNAL_FACTORY_REDIRECTION,

pkg/analyzer/lib/src/fasta/ast_builder.dart

@@ -5660,6 +5660,18 @@ class AstBuilder extends StackListener {
       handleRecoverableError(
           messageConstConstructorWithBody, bodyToken, bodyToken);
     }
+
+    if (modifiers?.externalKeyword != null) {
+      for (final formalParameter in parameters.parameters) {
+        if (formalParameter is FieldFormalParameterImpl) {
+          errorReporter.errorReporter?.reportErrorForToken(
+            ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS,
+            formalParameter.thisKeyword,
+          );
+        }
+      }
+    }
+
     var constructor = ConstructorDeclarationImpl(
       comment: comment,
       metadata: metadata,

pkg/analyzer/test/src/dart/parser/class_test.dart

@@ -2,6 +2,7 @@
 // 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:test_reflective_loader/test_reflective_loader.dart';
 
 import '../../diagnostics/parser_diagnostics.dart';
@@ -43,6 +44,69 @@ ClassDeclaration
       body: EmptyFunctionBody
         semicolon: ;
   rightBracket: }
+''');
+  }
+
+  test_constructor_external_fieldFormalParameter() {
+    final parseResult = parseStringWithErrors(r'''
+class A {
+  final int f;
+  external A(this.f);
+}
+''');
+    parseResult.assertErrors([
+      error(
+          ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS, 38, 4),
+    ]);
+
+    final node = parseResult.findNode.singleConstructorDeclaration;
+    assertParsedNodeText(node, r'''
+ConstructorDeclaration
+  externalKeyword: external
+  returnType: SimpleIdentifier
+    token: A
+  parameters: FormalParameterList
+    leftParenthesis: (
+    parameter: FieldFormalParameter
+      thisKeyword: this
+      period: .
+      name: f
+    rightParenthesis: )
+  body: EmptyFunctionBody
+    semicolon: ;
+''');
+  }
+
+  test_constructor_external_fieldInitializer() {
+    final parseResult = parseStringWithErrors(r'''
+class A {
+  final int f;
+  external A() : f = 0;
+}
+''');
+    parseResult.assertErrors([
+      error(ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_INITIALIZER, 40, 1),
+    ]);
+
+    final node = parseResult.findNode.singleConstructorDeclaration;
+    assertParsedNodeText(node, r'''
+ConstructorDeclaration
+  externalKeyword: external
+  returnType: SimpleIdentifier
+    token: A
+  parameters: FormalParameterList
+    leftParenthesis: (
+    rightParenthesis: )
+  separator: :
+  initializers
+    ConstructorFieldInitializer
+      fieldName: SimpleIdentifier
+        token: f
+      equals: =
+      expression: IntegerLiteral
+        literal: 0
+  body: EmptyFunctionBody
+    semicolon: ;
 ''');
   }
 }

pkg/front_end/messages.yaml

@@ -1270,9 +1270,10 @@ ExternalConstructorWithBody:
     - "class C { external C() {} }"
 
 ExternalConstructorWithFieldInitializers:
+  index: 178
   problemMessage: "An external constructor can't initialize fields."
   correctionMessage: "Try removing the field initializers, or removing the keyword 'external'."
-  analyzerCode: EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS
+  analyzerCode: ParserErrorCode.EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS
 
 ExternalFactoryWithBody:
   index: 86

tests/language/unsorted/external_test.dart

@@ -56,6 +56,8 @@ class Foo {
   //                               ^
   // [cfe] An external or native method can't have a body.
   external Foo.n24(this.x);
+  //               ^^^^
+  // [analyzer] SYNTACTIC_ERROR.EXTERNAL_CONSTRUCTOR_WITH_FIELD_INITIALIZERS
   //                    ^
   // [cfe] An external constructor can't initialize fields.
   external factory Foo.n25(val) = Bar;