Remove extra CompileTimeErrorCode.DUPLICATE_DEFINITION.

pkg/analyzer/lib/src/task/dart.dart

 // Copyright (c) 2015, 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.
 
 library analyzer.src.task.dart;
 
 import 'dart:collection';
 import 'dart:math' as math;
 
 import 'package:analyzer/src/context/cache.dart';
@@ skipping 397 matching lines @@
  *
  * The list will be empty if there were no errors, but will not be `null`.
  *
  * The result is only available for [LibrarySpecificUnit]s.
  */
 final ListResultDescriptor<AnalysisError> VERIFY_ERRORS =
     new ListResultDescriptor<AnalysisError>(
         'VERIFY_ERRORS', AnalysisError.NO_ERRORS);
 
 /**
+ * Remove [CompileTimeErrorCode.DUPLICATE_DEFINITION] errors from the given
+ * [errors] list.
+ */
+void removeDuplicateDefinitionErrors(List<AnalysisError> errors) {
+  if (errors.isNotEmpty) {
+    errors.removeWhere((error) {
+      ErrorCode errorCode = error.errorCode;
+      return errorCode == CompileTimeErrorCode.DUPLICATE_DEFINITION;
+    });
+  }
+}
+
+/**
  * A task that builds implicit constructors for a [ClassElement], or keeps
  * the existing explicit constructors if the class has them.
  */
 class BuildClassConstructorsTask extends SourceBasedAnalysisTask {
   /**
    * The name of the [CONSTRUCTORS] input for the superclass.
    */
   static const String SUPER_CONSTRUCTORS = 'SUPER_CONSTRUCTORS';
 
   /**
@@ skipping 726 matching lines @@
     // Resolve FunctionTypeAlias declarations.
     //
     TypeResolverVisitor visitor = new TypeResolverVisitor.con2(
         libraryElement, source, typeProvider, errorListener);
     for (CompilationUnitMember member in unit.declarations) {
       if (member is FunctionTypeAlias) {
         member.accept(visitor);
       }
     }
     //
+    // Prepare errors.
+    //
+    List<AnalysisError> errors = errorListener.errors;
+    removeDuplicateDefinitionErrors(errors);
+    //
     // Record outputs.
     //
-    outputs[BUILD_FUNCTION_TYPE_ALIASES_ERRORS] = errorListener.errors;
+    outputs[BUILD_FUNCTION_TYPE_ALIASES_ERRORS] = errors;
     outputs[RESOLVED_UNIT3] = unit;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(LibrarySpecificUnit target) {
     return <String, TaskInput>{
@@ skipping 1813 matching lines @@
     CompilationUnit unit = getRequiredInput(UNIT_INPUT);
     CompilationUnitElement unitElement = unit.element;
     TypeProvider typeProvider = getRequiredInput(TYPE_PROVIDER_INPUT);
     //
     // Resolve TypeName nodes.
     //
     TypeResolverVisitor visitor = new TypeResolverVisitor.con2(
         library, unitElement.source, typeProvider, errorListener);
     unit.accept(visitor);
     //
+    // Prepare errors.
+    //
+    List<AnalysisError> errors = errorListener.errors;
+    removeDuplicateDefinitionErrors(errors);
+    //
     // Record outputs.
     //
-    outputs[RESOLVE_TYPE_NAMES_ERRORS] = errorListener.errors;
+    outputs[RESOLVE_TYPE_NAMES_ERRORS] = errors;
     outputs[RESOLVED_UNIT4] = unit;
   }
 
   /**
    * Return a map from the names of the inputs of this kind of task to the task
    * input descriptors describing those inputs for a task with the
    * given [target].
    */
   static Map<String, TaskInput> buildInputs(LibrarySpecificUnit target) {
     return <String, TaskInput>{
@@ skipping 373 matching lines @@
   @override
   bool moveNext() {
     if (_newSources.isEmpty) {
       return false;
     }
     currentTarget = _newSources.first;
     _newSources.remove(currentTarget);
     return true;
   }
 }