Ignore 'expr is' outside of a statement.

pkg/analysis_server/test/services/correction/assist_test.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 test.services.correction.assist;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/edit/assist/assist_core.dart';
 import 'package:analysis_server/plugin/protocol/protocol.dart';
@@ skipping 2361 matching lines @@
   test_introduceLocalTestedType_BAD_notIsExpression() async {
     resolveTestUnit('''
 main(p) {
   if (p == null) {
   }
 }
 ''');
     await assertNoAssistAt('if (p', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE);
   }
 
+  test_introduceLocalTestedType_BAD_notStatement() async {
+    resolveTestUnit('''
+class C {
+  bool b;
+  C(v) : b = v is int;
+}''');
+    await assertNoAssistAt('is int', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE);
+  }
+
   test_introduceLocalTestedType_OK_if_is() async {
     resolveTestUnit('''
 class MyTypeName {}
 main(p) {
   if (p is MyTypeName) {
   }
   p = null;
 }
 ''');
     String expected = '''
@@ skipping 1554 matching lines @@
       positions.add(new Position(testFile, offset));
     }
     return positions;
   }
 
   void _setStartEndSelection() {
     offset = findOffset('// start\n') + '// start\n'.length;
     length = findOffset('// end') - offset;
   }
 }