[VM] Fix deserialization of arrays with type arguments in ApiMessageReader.

runtime/vm/snapshot_test.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/globals.h"
 
 #include "include/dart_tools_api.h"
 #include "platform/assert.h"
 #include "vm/class_finalizer.h"
 #include "vm/clustered_snapshot.h"
@@ skipping 582 matching lines @@
   EXPECT_EQ(Dart_CObject_kArray, root->type);
   EXPECT_EQ(kArrayLength, root->value.as_array.length);
   for (int i = 0; i < kArrayLength; i++) {
     Dart_CObject* element = root->value.as_array.values[i];
     EXPECT_EQ(Dart_CObject_kInt32, element->type);
     EXPECT_EQ(i, element->value.as_int32);
   }
   CheckEncodeDecodeMessage(root);
 }
 
+TEST_CASE(SerializeArrayWithTypeArgument) {
+  // Write snapshot with object content.
+  const int kArrayLength = 10;
+  Array& array = Array::Handle(Array::New(kArrayLength));
+
+  TypeArguments& type_args = TypeArguments::Handle();
+  type_args ^= TypeArguments::New(1);
+  type_args.SetTypeAt(0, Type::Handle(Type::ObjectType()));
+  type_args = type_args.Canonicalize();
+
+  array.SetTypeArguments(type_args);
+
+  Smi& smi = Smi::Handle();
+  for (int i = 0; i < kArrayLength; i++) {
+    smi ^= Smi::New(i);
+    array.SetAt(i, smi);
+  }
+  uint8_t* buffer;
+  MessageWriter writer(&buffer, &zone_allocator, &zone_deallocator, true);
+  writer.WriteMessage(array);
+  intptr_t buffer_len = writer.BytesWritten();
+
+  // Read object back from the snapshot.
+  MessageSnapshotReader reader(buffer, buffer_len, thread);
+  Array& serialized_array = Array::Handle();
+  serialized_array ^= reader.ReadObject();
+  EXPECT(array.CanonicalizeEquals(serialized_array));
+
+  // Read object back from the snapshot into a C structure.
+  ApiNativeScope scope;
+  ApiMessageReader api_reader(buffer, buffer_len);
+  Dart_CObject* root = api_reader.ReadMessage();
+  EXPECT_EQ(Dart_CObject_kArray, root->type);
+  EXPECT_EQ(kArrayLength, root->value.as_array.length);
+  for (int i = 0; i < kArrayLength; i++) {
+    Dart_CObject* element = root->value.as_array.values[i];
+    EXPECT_EQ(Dart_CObject_kInt32, element->type);
+    EXPECT_EQ(i, element->value.as_int32);
+  }
+  CheckEncodeDecodeMessage(root);
+}
+
 TEST_CASE(FailSerializeLargeArray) {
   Dart_CObject root;
   root.type = Dart_CObject_kArray;
   root.value.as_array.length = Array::kMaxElements + 1;
   root.value.as_array.values = NULL;
   ExpectEncodeFail(&root);
 }
 
 TEST_CASE(FailSerializeLargeNestedArray) {
   Dart_CObject parent;
@@ skipping 2479 matching lines @@
   StackZone zone(Thread::Current());
   uint8_t* buffer;
   MessageWriter writer(&buffer, &zone_allocator, &zone_deallocator, true);
   writer.WriteInlinedObjectHeader(kOmittedObjectId);
   // For performance, we'd like single-byte headers when ids are omitted.
   // If this starts failing, consider renumbering the snapshot ids.
   EXPECT_EQ(1, writer.BytesWritten());
 }
 
 }  // namespace dart