Add jsi::HostObject example to rn-tester (facebook#36909)

Summary:
Pull Request resolved: facebook#36909

Changelog: [Internal]

Reviewed By: javache

Differential Revision: D44978689

fbshipit-source-id: 0e31b5c37a7890744694706994ea672c3e619341

Author: christophpurrer

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.cpp

@@ -40,6 +40,19 @@ CustomEnumInt NativeCxxModuleExample::getCustomEnum(
   return arg;
 }
 
+std::shared_ptr<CustomHostObject> NativeCxxModuleExample::getCustomHostObject(
+    jsi::Runtime &rt) {
+  return std::make_shared<CustomHostObject>(
+      std::make_shared<CustomHostObjectRef>("answer", 42));
+}
+
+std::string NativeCxxModuleExample::consumeCustomHostObject(
+    jsi::Runtime &rt,
+    std::shared_ptr<CustomHostObject> arg) {
+  auto value = arg->getValue();
+  return value->a_ + std::to_string(value->b_);
+}
+
 NativeCxxModuleExampleCxxEnumFloat NativeCxxModuleExample::getNumEnum(
     jsi::Runtime &rt,
     NativeCxxModuleExampleCxxEnumInt arg) {

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.h

@@ -73,6 +73,30 @@ struct Bridging<CustomEnumInt> {
   }
 };
 
+#pragma mark - jsi::HostObjects
+template <typename T>
+class HostObjectWrapper : public jsi::HostObject {
+ public:
+  HostObjectWrapper(std::shared_ptr<T> value) : value_(std::move(value)) {}
+
+  std::shared_ptr<T> getValue() const {
+    return value_;
+  }
+
+  ~HostObjectWrapper() override = default;
+
+ private:
+  std::shared_ptr<T> value_;
+};
+
+struct CustomHostObjectRef {
+  CustomHostObjectRef(std::string a, int32_t b) : a_(a), b_(b) {}
+  std::string a_;
+  int32_t b_;
+};
+
+using CustomHostObject = HostObjectWrapper<CustomHostObjectRef>;
+
 #pragma mark - implementation
 class NativeCxxModuleExample
     : public NativeCxxModuleExampleCxxSpec<NativeCxxModuleExample> {
@@ -93,6 +117,12 @@ class NativeCxxModuleExample
 
   CustomEnumInt getCustomEnum(jsi::Runtime &rt, CustomEnumInt arg);
 
+  std::shared_ptr<CustomHostObject> getCustomHostObject(jsi::Runtime &rt);
+
+  std::string consumeCustomHostObject(
+      jsi::Runtime &rt,
+      std::shared_ptr<CustomHostObject> arg);
+
   NativeCxxModuleExampleCxxEnumFloat getNumEnum(
       jsi::Runtime &rt,
       NativeCxxModuleExampleCxxEnumInt arg);

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.js

@@ -54,11 +54,15 @@ export type ValueStruct = {|
   z: ObjectStruct,
 |};
 
+export type CustomHostObject = {};
+
 export interface Spec extends TurboModule {
   +getArray: (arg: Array<ObjectStruct | null>) => Array<ObjectStruct | null>;
   +getBool: (arg: boolean) => boolean;
   +getConstants: () => ConstantsStruct;
   +getCustomEnum: (arg: EnumInt) => EnumInt;
+  +getCustomHostObject: () => CustomHostObject;
+  +consumeCustomHostObject: (customHostObject: CustomHostObject) => string;
   +getNumEnum: (arg: EnumInt) => EnumFloat;
   +getStrEnum: (arg: EnumNone) => EnumStr;
   +getMap: (arg: {[key: string]: ?number}) => {[key: string]: ?number};

packages/rn-tester/js/examples/TurboModule/NativeCxxModuleExampleExample.js

@@ -87,6 +87,10 @@ class NativeCxxModuleExampleExample extends React.Component<{||}, State> {
     getBool: () => NativeCxxModuleExample?.getBool(true),
     getConstants: () => NativeCxxModuleExample?.getConstants(),
     getCustomEnum: () => NativeCxxModuleExample?.getCustomEnum(EnumInt.IB),
+    getCustomHostObject: () =>
+      NativeCxxModuleExample?.consumeCustomHostObject(
+        NativeCxxModuleExample?.getCustomHostObject(),
+      ),
     getNumEnum: () => NativeCxxModuleExample?.getNumEnum(EnumInt.IB),
     getStrEnum: () => NativeCxxModuleExample?.getStrEnum(EnumNone.NB),
     getNumber: () => NativeCxxModuleExample?.getNumber(99.95),