From 9a053fc4db1d926824cf579cbfcabcd664618f9b Mon Sep 17 00:00:00 2001
From: David Vacca <dvacca@fb.com>
Date: Sun, 2 Jun 2019 16:00:54 -0700
Subject: [PATCH] Create base MapBuffer class and tests

Summary: This diff creates the base classes for MapBuffer and its tests

Reviewed By: shergin

Differential Revision: D15550730

fbshipit-source-id: a5a47edebd7c3e1b8b2c3ad2006aee0f8bdb7866
---
 ReactCommon/fabric/mapbuffer/MapBuffer.cpp    | 18 +++++++++
 ReactCommon/fabric/mapbuffer/MapBuffer.h      | 37 +++++++++++++++++++
 .../fabric/mapbuffer/tests/MapBufferTest.cpp  | 14 +++++++
 3 files changed, 69 insertions(+)
 create mode 100644 ReactCommon/fabric/mapbuffer/MapBuffer.cpp
 create mode 100644 ReactCommon/fabric/mapbuffer/MapBuffer.h
 create mode 100644 ReactCommon/fabric/mapbuffer/tests/MapBufferTest.cpp

diff --git a/ReactCommon/fabric/mapbuffer/MapBuffer.cpp b/ReactCommon/fabric/mapbuffer/MapBuffer.cpp
new file mode 100644
index 00000000000..330890f8832
--- /dev/null
+++ b/ReactCommon/fabric/mapbuffer/MapBuffer.cpp
@@ -0,0 +1,18 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "MapBuffer.h"
+
+namespace facebook {
+namespace react {
+
+MapBuffer::MapBuffer() {}
+
+MapBuffer::~MapBuffer() {}
+
+} // namespace react
+} // namespace facebook
diff --git a/ReactCommon/fabric/mapbuffer/MapBuffer.h b/ReactCommon/fabric/mapbuffer/MapBuffer.h
new file mode 100644
index 00000000000..e92a6f40635
--- /dev/null
+++ b/ReactCommon/fabric/mapbuffer/MapBuffer.h
@@ -0,0 +1,37 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <string>
+
+namespace facebook {
+namespace react {
+
+/**
+ * MapBuffer is an optimized map format for transferring data like props between
+ * C++ and other platforms The implemenation of this map is optimized to:
+ * - be compact to optimize space when sparse (sparse is the common case).
+ * - be accessible through JNI with zero/minimal copying via ByteBuffer.
+ * - be Have excellent C++ single-write and many-read performance by maximizing
+ *   CPU cache performance through compactness, data locality, and fixed offsets
+ *   where possible.
+ * - be optimized for iteration and intersection against other maps, but with
+ *   reasonably good random access as well.
+ * - Work recursively for nested maps/arrays.
+ * - Supports dynamic types that map to JSON.
+ * - Don't require mutability - single-write on creation.
+ * - have minimal APK size and build time impact.
+ */
+class MapBuffer {
+ public:
+  MapBuffer();
+  virtual ~MapBuffer();
+};
+
+} // namespace react
+} // namespace facebook
diff --git a/ReactCommon/fabric/mapbuffer/tests/MapBufferTest.cpp b/ReactCommon/fabric/mapbuffer/tests/MapBufferTest.cpp
new file mode 100644
index 00000000000..591f24f22cf
--- /dev/null
+++ b/ReactCommon/fabric/mapbuffer/tests/MapBufferTest.cpp
@@ -0,0 +1,14 @@
+/**
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include <memory>
+
+#include <gtest/gtest.h>
+
+TEST(MapBufferTest, testSomething) {
+  // TODO
+}