Detect missing with clause in mixing applications

runtime/vm/parser.cc

 // Copyright (c) 2012, 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.
 
 #include "vm/parser.h"
 
 #include "lib/invocation_mirror.h"
 #include "platform/utils.h"
 #include "vm/bootstrap.h"
 #include "vm/class_finalizer.h"
@@ skipping 3892 matching lines @@
                "class '%s' may not extend 'dynamic'",
                class_name.ToCString());
     }
     if (super_type.IsTypeParameter()) {
       ErrorMsg(type_pos,
                "class '%s' may not extend type parameter '%s'",
                class_name.ToCString(),
                String::Handle(super_type.UserVisibleName()).ToCString());
     }
     // The class finalizer will check whether the super type is malbounded.
+    if (is_mixin_declaration) {
+      if (CurrentToken() != Token::kWITH) {
+        ErrorMsg("mixin application clause 'with type' expected");
+      }
+      cls.set_is_mixin_app_alias();
+      cls.set_is_synthesized_class();
+    }
     if (CurrentToken() == Token::kWITH) {
       super_type = ParseMixins(super_type);
     }
-    if (is_mixin_declaration) {
-      cls.set_is_mixin_app_alias();
-      cls.set_is_synthesized_class();
-    }
   } else {
     // No extends clause: implicitly extend Object, unless Object itself.
     if (!cls.IsObjectClass()) {
       super_type = Type::ObjectType();
     }
   }
   ASSERT(!super_type.IsNull() || cls.IsObjectClass());
   cls.set_super_type(super_type);
 
   if (CurrentToken() == Token::kIMPLEMENTS) {
@@ skipping 6823 matching lines @@
 void Parser::SkipQualIdent() {
   ASSERT(IsIdentifier());
   ConsumeToken();
   if (CurrentToken() == Token::kPERIOD) {
     ConsumeToken();  // Consume the kPERIOD token.
     ExpectIdentifier("identifier expected after '.'");
   }
 }
 
 }  // namespace dart