Validation of `@protected` method invocations.

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

 // Copyright (c) 2014, 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.generated.error;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart' show AstNode;
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 3515 matching lines @@
    *
    * Parameters:
    * 0: the name of the right hand side type
    * 1: the name of the left hand side type
    */
   static const HintCode INVALID_ASSIGNMENT = const HintCode(
       'INVALID_ASSIGNMENT',
       "A value of type '{0}' cannot be assigned to a variable of type '{1}'");
 
   /**
+   * This hint is generated anywhere where a member annotated with `@protected`
+   * is used outside an instance member of a subclass.
+   *
+   * Parameters:
+   * 0: the name of the member
+   * 1: the name of the defining class
+   */
+  static const HintCode INVALID_USE_OF_PROTECTED_MEMBER = const HintCode(
+      'INVALID_USE_OF_PROTECTED_MEMBER',
+      "The member '{0}' can only be used within instance members of subclasses of '{1}'");
+
+  /**
    * Generate a hint for methods or functions that have a return type, but do
    * not have a non-void return statement on all branches. At the end of methods
    * or functions with no return, Dart implicitly returns `null`, avoiding these
    * implicit returns is considered a best practice.
    *
    * Parameters:
    * 0: the name of the declared return type
    */
   static const HintCode MISSING_RETURN = const HintCode(
       'MISSING_RETURN',
@@ skipping 2145 matching lines @@
    * Initialize a newly created error code to have the given [name].
    */
   const TodoCode(String name) : super(name, "{0}");
 
   @override
   ErrorSeverity get errorSeverity => ErrorSeverity.INFO;
 
   @override
   ErrorType get type => ErrorType.TODO;
 }