Report duplicated field names in record literals

Change-Id: Ifc5c3a06c7f489b00421f5b1af47df52615694d5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/256200
Reviewed-by: Konstantin Shcheglov <scheglov@google.com>
Commit-Queue: Brian Wilkerson <brianwilkerson@google.com>
Reviewed-by: Samuel Rawlins <srawlins@google.com>

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

@@ -354,6 +354,8 @@ CompileTimeErrorCode.DUPLICATE_CONSTRUCTOR_NAME:
   status: needsEvaluation
 CompileTimeErrorCode.DUPLICATE_DEFINITION:
   status: needsEvaluation
+CompileTimeErrorCode.DUPLICATE_FIELD_NAME:
+  status: needsEvaluation
 CompileTimeErrorCode.DUPLICATE_FIELD_FORMAL_PARAMETER:
   status: needsEvaluation
 CompileTimeErrorCode.DUPLICATE_NAMED_ARGUMENT:

pkg/analyzer/lib/error/error.dart

@@ -159,6 +159,7 @@ const List<ErrorCode> errorCodeValues = [
   CompileTimeErrorCode.DUPLICATE_CONSTRUCTOR_DEFAULT,
   CompileTimeErrorCode.DUPLICATE_CONSTRUCTOR_NAME,
   CompileTimeErrorCode.DUPLICATE_DEFINITION,
+  CompileTimeErrorCode.DUPLICATE_FIELD_NAME,
   CompileTimeErrorCode.DUPLICATE_FIELD_FORMAL_PARAMETER,
   CompileTimeErrorCode.DUPLICATE_NAMED_ARGUMENT,
   CompileTimeErrorCode.DUPLICATE_PART,

pkg/analyzer/lib/src/dart/resolver/record_literal_resolver.dart

@@ -0,0 +1,47 @@
+// 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 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/error/listener.dart';
+import 'package:analyzer/src/dart/ast/ast.dart';
+import 'package:analyzer/src/diagnostic/diagnostic_factory.dart';
+import 'package:analyzer/src/generated/resolver.dart';
+
+/// Helper for resolving [RecordLiteral]s.
+class RecordLiteralResolver {
+  final ResolverVisitor _resolver;
+
+  RecordLiteralResolver({
+    required ResolverVisitor resolver,
+  }) : _resolver = resolver;
+
+  ErrorReporter get errorReporter => _resolver.errorReporter;
+
+  /// Report any named fields in the record literal [node] that use a previously
+  /// defined name.
+  void reportDuplicateFieldDefinitions(RecordLiteralImpl node) {
+    var fields = node.fields;
+    var usedNames = <String, NamedExpression>{};
+    for (var field in fields) {
+      if (field is NamedExpression) {
+        var nameNode = field.name.label;
+        var name = nameNode.name;
+        var previousField = usedNames[name];
+        if (previousField != null) {
+          errorReporter.reportError(DiagnosticFactory()
+              .duplicateFieldDefinition(
+                  errorReporter.source, field, previousField));
+        } else {
+          usedNames[name] = field;
+        }
+      }
+    }
+  }
+
+  void resolve(RecordLiteralImpl node, {required DartType? contextType}) {
+    // TODO(brianwilkerson) Move resolution from the `visitRecordLiteral`
+    //  methods of `ResolverVisitor` and `StaticTypeAnalyzer` to this class.
+  }
+}

pkg/analyzer/lib/src/diagnostic/diagnostic_factory.dart

@@ -61,6 +61,29 @@ class DiagnosticFactory {
     );
   }
 
+  /// Return a diagnostic indicating that [duplicateField] reuses a name
+  /// already used by [originalField].
+  AnalysisError duplicateFieldDefinition(Source source,
+      NamedExpression duplicateField, NamedExpression originalField) {
+    var duplicateNode = duplicateField.name.label;
+    var duplicateName = duplicateNode.name;
+    return AnalysisError(
+      source,
+      duplicateNode.offset,
+      duplicateNode.length,
+      CompileTimeErrorCode.DUPLICATE_FIELD_NAME,
+      [duplicateName],
+      [
+        DiagnosticMessageImpl(
+            filePath: source.fullName,
+            length: duplicateName.length,
+            message: 'The first ',
+            offset: originalField.name.label.offset,
+            url: source.uri.toString()),
+      ],
+    );
+  }
+
   /// Return a diagnostic indicating that the [duplicateElement] (in a constant
   /// set) is a duplicate of the [originalElement].
   AnalysisError equalElementsInConstSet(

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

@@ -1130,6 +1130,12 @@ class CompileTimeErrorCode extends AnalyzerErrorCode {
     hasPublishedDocs: true,
   );
 
+  static const CompileTimeErrorCode DUPLICATE_FIELD_NAME = CompileTimeErrorCode(
+    'DUPLICATE_FIELD_NAME',
+    "The field name '{0}' is already used.",
+    correctionMessage: "Try renaming the field.",
+  );
+
   ///  Parameters:
   ///  0: the name of the parameter that was duplicated
   static const CompileTimeErrorCode DUPLICATE_NAMED_ARGUMENT =

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

@@ -50,6 +50,7 @@ import 'package:analyzer/src/dart/resolver/postfix_expression_resolver.dart';
 import 'package:analyzer/src/dart/resolver/prefix_expression_resolver.dart';
 import 'package:analyzer/src/dart/resolver/prefixed_identifier_resolver.dart';
 import 'package:analyzer/src/dart/resolver/property_element_resolver.dart';
+import 'package:analyzer/src/dart/resolver/record_literal_resolver.dart';
 import 'package:analyzer/src/dart/resolver/scope.dart';
 import 'package:analyzer/src/dart/resolver/simple_identifier_resolver.dart';
 import 'package:analyzer/src/dart/resolver/this_lookup.dart';
@@ -248,6 +249,9 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
   late final PropertyElementResolver _propertyElementResolver =
       PropertyElementResolver(this);
 
+  late final RecordLiteralResolver _recordLiteralResolver =
+      RecordLiteralResolver(resolver: this);
+
   late final AnnotationResolver _annotationResolver = AnnotationResolver(this);
 
   final bool genericMetadataIsEnabled;
@@ -2215,6 +2219,7 @@ class ResolverVisitor extends ThrowingAstVisitor<void>
       }
     }
     typeAnalyzer.visitRecordLiteral(node, contextType: contextType);
+    _recordLiteralResolver.reportDuplicateFieldDefinitions(node);
   }
 
   @override

pkg/analyzer/messages.yaml

@@ -3361,6 +3361,9 @@ CompileTimeErrorCode:
       int x = 0;
       int y = 1;
       ```
+  DUPLICATE_FIELD_NAME:
+    problemMessage: The field name '{0}' is already used.
+    correctionMessage: Try renaming the field.
   DUPLICATE_FIELD_FORMAL_PARAMETER:
     problemMessage: "The field '{0}' can't be initialized by multiple parameters in the same constructor."
     correctionMessage: Try removing one of the parameters, or using different fields.

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

@@ -0,0 +1,32 @@
+// 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 '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(DuplicateFieldNameTest);
+  });
+}
+
+@reflectiveTest
+class DuplicateFieldNameTest extends PubPackageResolutionTest {
+  test_duplicated() async {
+    await assertErrorsInCode(r'''
+var r = (a: 1, a: 2);
+''', [
+      error(CompileTimeErrorCode.DUPLICATE_FIELD_NAME, 15, 1,
+          contextMessages: [message('/home/test/lib/test.dart', 9, 1)]),
+    ]);
+  }
+
+  test_notDuplicated() async {
+    await assertNoErrorsInCode(r'''
+var r = (a: 1, b: 2);
+''');
+  }
+}

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

@@ -153,6 +153,7 @@ import 'duplicate_constructor_name_test.dart' as duplicate_constructor_name;
 import 'duplicate_definition_test.dart' as duplicate_definition;
 import 'duplicate_field_formal_parameter_test.dart'
     as duplicate_field_formal_parameter;
+import 'duplicate_field_name_test.dart' as duplicate_field_name;
 import 'duplicate_hidden_name_test.dart' as duplicate_hidden_name;
 import 'duplicate_ignore_test.dart' as duplicate_ignore;
 import 'duplicate_import_test.dart' as duplicate_import;
@@ -904,6 +905,7 @@ main() {
     duplicate_constructor_default.main();
     duplicate_constructor_name.main();
     duplicate_definition.main();
+    duplicate_field_name.main();
     duplicate_field_formal_parameter.main();
     duplicate_hidden_name.main();
     duplicate_ignore.main();