Remove NullPointerException.

runtime/lib/regexp.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 "platform/assert.h"
 #include "vm/bootstrap_natives.h"
 #include "vm/exceptions.h"
 #include "vm/native_entry.h"
 #include "vm/object.h"
 
 #include "lib/regexp_jsc.h"
 
 namespace dart {
 
-static void CheckAndThrowExceptionIfNull(const Instance& obj) {
-  if (obj.IsNull()) {
-    GrowableArray<const Object*> args;
-    Exceptions::ThrowByType(Exceptions::kNullPointer, args);
-  }
-}
-
 
 DEFINE_NATIVE_ENTRY(JSSyntaxRegExp_factory, 4) {
   ASSERT(AbstractTypeArguments::CheckedHandle(
       arguments->NativeArgAt(0)).IsNull());
-  const Instance& arg1 = Instance::CheckedHandle(arguments->NativeArgAt(1));
-  CheckAndThrowExceptionIfNull(arg1);

[Lasse Reichstein Nielsen, 2012/11/19 15:02:48]

Was this code actually necessary to test for getting zero arguments?

[regis, 2012/11/19 19:45:31]

I am not familiar with this code. The first argument, NativeArgAt(0), to the
factory is the type argument vector. In this case, we check that it is null,
because JSSyntaxRegExp is not generic.

The second argument, NativeArgAt(1), is checked for null. I have no idea why.
This would only make sense if the Jscre::Compile call cannot handle a null
pattern.

   GET_NATIVE_ARGUMENT(String, pattern, arguments->NativeArgAt(1));
   GET_NATIVE_ARGUMENT(Instance, handle_multi_line, arguments->NativeArgAt(2));
   GET_NATIVE_ARGUMENT(Instance, handle_ignore_case, arguments->NativeArgAt(3));
   bool ignore_case = handle_ignore_case.raw() == Bool::True();
   bool multi_line = handle_multi_line.raw() == Bool::True();
   return Jscre::Compile(pattern, multi_line, ignore_case);
 }
 
 
 DEFINE_NATIVE_ENTRY(JSSyntaxRegExp_getPattern, 1) {
@@ skipping 30 matching lines @@
   args.Add(&pattern);
   args.Add(&errmsg);
   Exceptions::ThrowByType(Exceptions::kIllegalJSRegExp, args);
   return Object::null();
 }
 
 
 DEFINE_NATIVE_ENTRY(JSSyntaxRegExp_ExecuteMatch, 3) {
   const JSRegExp& regexp = JSRegExp::CheckedHandle(arguments->NativeArgAt(0));
   ASSERT(!regexp.IsNull());
-  const Instance& arg1 = Instance::CheckedHandle(arguments->NativeArgAt(1));
-  CheckAndThrowExceptionIfNull(arg1);
   GET_NATIVE_ARGUMENT(String, str, arguments->NativeArgAt(1));
   GET_NATIVE_ARGUMENT(Smi, start_index, arguments->NativeArgAt(2));
   return Jscre::Execute(regexp, str, start_index.Value());
 }
 
 }  // namespace dart