C++ style enums 1/N: Generator

Summary:
This adds logic to the enum generator to generate C++ style scoped enums.

This gives us a few nicities over C enums, even if both must exist:
1. We can add types and keep unsgined enums directly in bitfields
2. Style/readability
3. Avoiding implicit int conversion

Differential Revision: D49267996

fbshipit-source-id: 0ba9a79e19616f55abdc15012fbfd26933c6d179

yoga/enums/NodeType.h

@@ -0,0 +1,45 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+// @generated by enums.py
+// clang-format off
+#pragma once
+
+#include <cstdint>
+#include <yoga/YGEnums.h>
+#include <yoga/enums/YogaEnums.h>
+
+namespace facebook::yoga {
+
+enum class NodeType : uint8_t {
+  Default = YGNodeTypeDefault,
+  Text = YGNodeTypeText,
+};
+
+template <>
+constexpr inline int32_t ordinalCount<NodeType>() {
+  return 2;
+} 
+
+template <>
+constexpr inline int32_t bitCount<NodeType>() {
+  return 1;
+} 
+
+constexpr inline NodeType scopedEnum(YGNodeType unscoped) {
+  return static_cast<NodeType>(unscoped);
+}
+
+constexpr inline YGNodeType unscopedEnum(NodeType scoped) {
+  return static_cast<YGNodeType>(scoped);
+}
+
+inline const char* toString(NodeType e) {
+  return YGNodeTypeToString(unscopedEnum(e));
+}
+
+} // namespace facebook::yoga