Verify that required param constants are accessible outside the declaring lib (#26440).

pkg/analyzer/test/generated/hint_code_test.dart

 // Copyright (c) 2016, 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.test.generated.hint_code_test;
 
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/source_io.dart';
 import 'package:unittest/unittest.dart';
@@ skipping 1720 matching lines @@
 }
 f() {
   new A().m();
 }
 ''');
     computeLibrarySourceErrors(source);
     assertErrors(source, [HintCode.MISSING_REQUIRED_PARAM_WITH_DETAILS]);
     verify([source]);
   }
 
+  void test_required_method_param_in_other_lib() {
+    addNamedSource(
+        '/a_lib.dart',
+        r'''
+library a_lib;
+import 'package:meta/meta.dart';
+class A {
+  void m({@Required('must specify an `a`') int a}) {}
+}
+''');
+
+    Source source = addSource(r'''
+import "a_lib.dart";
+f() {
+  new A().m();
+}
+''');
+
+    computeLibrarySourceErrors(source);
+    assertErrors(source, [HintCode.MISSING_REQUIRED_PARAM_WITH_DETAILS]);
+    verify([source]);
+  }
+
   void test_typeCheck_type_is_Null() {
     Source source = addSource(r'''
 m(i) {
   bool b = i is Null;
 }''');
     computeLibrarySourceErrors(source);
     assertErrors(source, [HintCode.TYPE_CHECK_IS_NULL]);
     verify([source]);
   }
 
   void test_typeCheck_type_not_Null() {
     Source source = addSource(r'''
 m(i) {
   bool b = i is! Null;
 }''');
     computeLibrarySourceErrors(source);
     assertErrors(source, [HintCode.TYPE_CHECK_IS_NOT_NULL]);
     verify([source]);
   }
 
   void test_undefinedIdentifier_importHide() {
     Source source = addSource(r'''
 library L;
 import 'lib1.dart' hide a;''');
     addNamedSource("/lib1.dart", "library lib1;");
     computeLibrarySourceErrors(source);
     assertErrors(
-        source,
-        [HintCode.UNUSED_IMPORT, HintCode.UNDEFINED_HIDDEN_NAME]);
+        source, [HintCode.UNUSED_IMPORT, HintCode.UNDEFINED_HIDDEN_NAME]);
     verify([source]);
   }
 
   void test_undefinedIdentifier_importShow() {
     Source source = addSource(r'''
 library L;
 import 'lib1.dart' show a;''');
     addNamedSource("/lib1.dart", "library lib1;");
     computeLibrarySourceErrors(source);
     assertErrors(
-        source,
-        [HintCode.UNUSED_IMPORT, HintCode.UNDEFINED_SHOWN_NAME]);
+        source, [HintCode.UNUSED_IMPORT, HintCode.UNDEFINED_SHOWN_NAME]);
     verify([source]);
   }
 
   void test_undefinedIdentifier_exportHide() {
     Source source = addSource(r'''
 library L;
 export 'lib1.dart' hide a;''');
     addNamedSource("/lib1.dart", "library lib1;");
     computeLibrarySourceErrors(source);
     assertErrors(source, [HintCode.UNDEFINED_HIDDEN_NAME]);
@@ skipping 1542 matching lines @@
   n() {
     var a = m(), b = m();
   }
 }''');
     computeLibrarySourceErrors(source);
     assertErrors(
         source, [HintCode.USE_OF_VOID_RESULT, HintCode.USE_OF_VOID_RESULT]);
     verify([source]);
   }
 }