[snapshot] revisit snapshot API.

test/cctest/test-serialize.cc

 // Copyright 2007-2010 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 1899 matching lines @@
     blob =
         creator.CreateBlob(v8::SnapshotCreator::FunctionCodeHandling::kClear);
   }
 
   v8::Isolate::CreateParams params;
   params.snapshot_blob = &blob;
   params.array_buffer_allocator = CcTest::array_buffer_allocator();
   v8::Isolate* isolate = v8::Isolate::New(params);
   {
     v8::Isolate::Scope isolate_scope(isolate);
-    v8::ExtensionConfiguration* no_extension = nullptr;
-    v8::Local<v8::ObjectTemplate> no_template = v8::Local<v8::ObjectTemplate>();
-    v8::Local<v8::Value> no_object = v8::Local<v8::Value>();
     {
       v8::HandleScope handle_scope(isolate);
       v8::Local<v8::Context> context =
-          v8::Context::New(isolate, no_extension, no_template, no_object, 0);
+          v8::Context::FromSnapshot(isolate, 0).ToLocalChecked();
       v8::Context::Scope context_scope(context);
       ExpectInt32("f()", 1);
     }
     {
       v8::HandleScope handle_scope(isolate);
       v8::Local<v8::Context> context =
-          v8::Context::New(isolate, no_extension, no_template, no_object, 1);
+          v8::Context::FromSnapshot(isolate, 1).ToLocalChecked();
       v8::Context::Scope context_scope(context);
       ExpectInt32("f()", 2);
     }
     {
       v8::HandleScope handle_scope(isolate);
       v8::Local<v8::Context> context =
-          v8::Context::New(isolate, no_extension, no_template, no_object, 2);
+          v8::Context::FromSnapshot(isolate, 2).ToLocalChecked();
       v8::Context::Scope context_scope(context);
       ExpectUndefined("this.f");
     }
   }
 
   isolate->Dispose();
   delete[] blob.data;
 }
 
 static void SerializedCallback(
@@ skipping 37 matching lines @@
   // Deserialize with the original external reference.
   {
     v8::Isolate::CreateParams params;
     params.snapshot_blob = &blob;
     params.array_buffer_allocator = CcTest::array_buffer_allocator();
     params.external_references = original_external_references;
     v8::Isolate* isolate = v8::Isolate::New(params);
     {
       v8::Isolate::Scope isolate_scope(isolate);
       v8::HandleScope handle_scope(isolate);
-      v8::ExtensionConfiguration* no_extension = nullptr;
-      v8::Local<v8::ObjectTemplate> no_template =
-          v8::Local<v8::ObjectTemplate>();
-      v8::Local<v8::Value> no_object = v8::Local<v8::Value>();
       v8::Local<v8::Context> context =
-          v8::Context::New(isolate, no_extension, no_template, no_object, 0);
+          v8::Context::FromSnapshot(isolate, 0).ToLocalChecked();
       v8::Context::Scope context_scope(context);
       ExpectInt32("f()", 42);
     }
     isolate->Dispose();
   }
 
   // Deserialize with the some other external reference.
   {
     v8::Isolate::CreateParams params;
     params.snapshot_blob = &blob;
     params.array_buffer_allocator = CcTest::array_buffer_allocator();
     params.external_references = replaced_external_references;
     v8::Isolate* isolate = v8::Isolate::New(params);
     {
       v8::Isolate::Scope isolate_scope(isolate);
       v8::HandleScope handle_scope(isolate);
-      v8::ExtensionConfiguration* no_extension = nullptr;
-      v8::Local<v8::ObjectTemplate> no_template =
-          v8::Local<v8::ObjectTemplate>();
-      v8::Local<v8::Value> no_object = v8::Local<v8::Value>();
       v8::Local<v8::Context> context =
-          v8::Context::New(isolate, no_extension, no_template, no_object, 0);
+          v8::Context::FromSnapshot(isolate, 0).ToLocalChecked();
       v8::Context::Scope context_scope(context);
       ExpectInt32("f()", 1337);
     }
     isolate->Dispose();
   }
   delete[] blob.data;
 }
 
 TEST(SnapshotCreatorTemplates) {
   DisableTurbofan();
@@ skipping 25 matching lines @@
     v8::Isolate::CreateParams params;
     params.snapshot_blob = &blob;
     params.array_buffer_allocator = CcTest::array_buffer_allocator();
     params.external_references = original_external_references;
     v8::Isolate* isolate = v8::Isolate::New(params);
     {
       v8::Isolate::Scope isolate_scope(isolate);
       {
         // Create a new context without a new object template.
         v8::HandleScope handle_scope(isolate);
-        v8::ExtensionConfiguration* no_extension = nullptr;
-        v8::Local<v8::ObjectTemplate> no_template =
-            v8::Local<v8::ObjectTemplate>();
-        v8::Local<v8::Value> no_object = v8::Local<v8::Value>();
         v8::Local<v8::Context> context =
-            v8::Context::New(isolate, no_extension, no_template, no_object, 0);
+            v8::Context::FromSnapshot(isolate, 0).ToLocalChecked();
         v8::Context::Scope context_scope(context);
         ExpectInt32("f()", 42);
 
         // Retrieve the snapshotted object template.
         v8::Local<v8::ObjectTemplate> obj_template =
-            v8::ObjectTemplate::FromSnapshot(isolate, 1);
+            v8::ObjectTemplate::FromSnapshot(isolate, 1).ToLocalChecked();
         CHECK(!obj_template.IsEmpty());
         v8::Local<v8::Object> object =
             obj_template->NewInstance(context).ToLocalChecked();
         CHECK(context->Global()->Set(context, v8_str("o"), object).FromJust());
         ExpectInt32("o.f()", 42);
         // Check that it instantiates to the same prototype.
         ExpectTrue("o.f.prototype === f.prototype");
 
         // Retrieve the snapshotted function template.
         v8::Local<v8::FunctionTemplate> fun_template =
-            v8::FunctionTemplate::FromSnapshot(isolate, 0);
+            v8::FunctionTemplate::FromSnapshot(isolate, 0).ToLocalChecked();
         CHECK(!fun_template.IsEmpty());
         v8::Local<v8::Function> fun =
             fun_template->GetFunction(context).ToLocalChecked();
         CHECK(context->Global()->Set(context, v8_str("g"), fun).FromJust());
         ExpectInt32("g()", 42);
         // Check that it instantiates to the same prototype.
         ExpectTrue("g.prototype === f.prototype");
+
+        // Accessing out of bound returns empty MaybeHandle.
+        CHECK(v8::ObjectTemplate::FromSnapshot(isolate, 2).IsEmpty());
+        CHECK(v8::FunctionTemplate::FromSnapshot(isolate, 2).IsEmpty());
+        CHECK(v8::Context::FromSnapshot(isolate, 2).IsEmpty());
       }
 
       {
         // Create a context with a new object template. It is merged into the
         // deserialized global object.
         v8::HandleScope handle_scope(isolate);
         v8::ExtensionConfiguration* no_extension = nullptr;
         v8::Local<v8::ObjectTemplate> global_template =
             v8::ObjectTemplate::New(isolate);
         global_template->Set(
             v8_str("g"),
             v8::FunctionTemplate::New(isolate, SerializedCallbackReplacement));
-        v8::Local<v8::Value> no_object = v8::Local<v8::Value>();
-        v8::Local<v8::Context> context = v8::Context::New(
-            isolate, no_extension, global_template, no_object, 0);
+        v8::Local<v8::Context> context =
+            v8::Context::FromSnapshot(isolate, 0, no_extension, global_template)
+                .ToLocalChecked();
         v8::Context::Scope context_scope(context);
         ExpectInt32("g()", 1337);
         ExpectInt32("f()", 42);
       }
     }
     isolate->Dispose();
   }
   delete[] blob.data;
 }
 
 TEST(SerializationMemoryStats) {
   FLAG_profile_deserialization = true;
   FLAG_always_opt = false;
   v8::StartupData blob = v8::V8::CreateSnapshotDataBlob();
   delete[] blob.data;
 }