Remember and reuse derived map for external arrays

test/cctest/test-api.cc

 // Copyright 2007-2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 11580 matching lines @@
                         "      large_array[offset + 4 * i + 2] != 0 ||"
                         "      large_array[offset + 4 * i + 3] != 127) {"
                         "    failed = true;"
                         "  }"
                         "}"
                         "!failed;");
     CHECK_EQ(true, result->BooleanValue());
     free(large_array_data);
   }
 
+  // The "" property descriptor is overloaded to store information about
+  // the external array. Ensure that setting and accessing the "" property
+  // works (it should overwrite the information cached about the external
+  // array in the DescriptorArray) in various situations.
+  result = CompileRun("ext_array[\"\"] = 23; ext_array[\"\"]");

[Mads Ager (chromium), 2011/03/22 18:57:25]

You can use '' for the empty string in JS code here and below.

[danno, 2011/03/23 09:56:52]

Done.

+  CHECK_EQ(23, result->Int32Value());
+
+  // Property "" set after the external array is associated with the object.
+  {
+    v8::Handle<v8::Object> obj2 = v8::Object::New();
+    obj2->Set(v8_str("ee_test_field"), v8::Int32::New(256));
+    obj2->Set(v8_str(""), v8::Int32::New(1503));
+    // Set the elements to be the external array.
+    obj2->SetIndexedPropertiesToExternalArrayData(array_data,
+                                                  array_type,
+                                                  kElementCount);
+    context->Global()->Set(v8_str("ext_array"), obj2);
+    result = CompileRun("ext_array[\"\"]");
+    CHECK_EQ(1503, result->Int32Value());
+  }
+
+  // Property "" set after the external array is associated with the object.
+  {
+    v8::Handle<v8::Object> obj2 = v8::Object::New();
+    obj2->Set(v8_str("ee_test_field_2"), v8::Int32::New(256));
+    // Set the elements to be the external array.
+    obj2->SetIndexedPropertiesToExternalArrayData(array_data,
+                                                  array_type,
+                                                  kElementCount);
+    obj2->Set(v8_str(""), v8::Int32::New(1503));
+    context->Global()->Set(v8_str("ext_array"), obj2);
+    result = CompileRun("ext_array[\"\"]");
+    CHECK_EQ(1503, result->Int32Value());
+  }
+
+  // Should reuse the map from previous test.
+  {
+    v8::Handle<v8::Object> obj2 = v8::Object::New();
+    obj2->Set(v8_str("ee_test_field_2"), v8::Int32::New(256));
+    // Set the elements to be the external array. Should re-use the map
+    // from previous test.
+    obj2->SetIndexedPropertiesToExternalArrayData(array_data,
+                                                  array_type,
+                                                  kElementCount);
+    context->Global()->Set(v8_str("ext_array"), obj2);
+    result = CompileRun("ext_array[\"\"]");
+  }
+
+  // Property "" is a constant function that shouldn't not be interfered with
+  // when an external array is set.
+  {
+    v8::Handle<v8::Object> obj2 = v8::Object::New();
+    // Start
+    obj2->Set(v8_str("ee_test_field3"), v8::Int32::New(256));
+
+    // Add a constant function to an object.
+    context->Global()->Set(v8_str("ext_array"), obj2);
+    result = CompileRun("ext_array[\"\"] = function() {return 1503;};"
+                        "ext_array[\"\"]();");
+
+    // Add an external array transition to the same map that
+    // has the constant transition.
+    v8::Handle<v8::Object> obj3 = v8::Object::New();
+    obj3->Set(v8_str("ee_test_field3"), v8::Int32::New(256));
+    obj3->SetIndexedPropertiesToExternalArrayData(array_data,
+                                                  array_type,
+                                                  kElementCount);
+    context->Global()->Set(v8_str("ext_array"), obj3);
+  }
+
+  // If a external array transition is in the map, it should get clobbered
+  // by a constant function.
+  {
+    // Add an external array transition.
+    v8::Handle<v8::Object> obj3 = v8::Object::New();
+    obj3->Set(v8_str("ee_test_field4"), v8::Int32::New(256));
+    obj3->SetIndexedPropertiesToExternalArrayData(array_data,
+                                                  array_type,
+                                                  kElementCount);
+
+    // Add a constant function to the same map that just got an external array
+    // transition.
+    v8::Handle<v8::Object> obj2 = v8::Object::New();
+    obj2->Set(v8_str("ee_test_field4"), v8::Int32::New(256));
+    context->Global()->Set(v8_str("ext_array"), obj2);
+    result = CompileRun("ext_array[\"\"] = function() {return 1503;};"
+                        "ext_array[\"\"]();");
+  }
+
   free(array_data);
 }
 
 
 THREADED_TEST(ExternalByteArray) {
   ExternalArrayTestHelper<i::ExternalByteArray, int8_t>(
       v8::kExternalByteArray,
       -128,
       127);
 }
@@ skipping 1864 matching lines @@
   v8::Handle<v8::Function> define_property =
       CompileRun("(function() {"
                  "  Object.defineProperty("
                  "    this,"
                  "    1,"
                  "    { configurable: true, enumerable: true, value: 3 });"
                  "})").As<Function>();
   context->DetachGlobal();
   define_property->Call(proxy, 0, NULL);
 }