react-native code-gen > C++ TurboModules enum example (#36083)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/36083

Changelog: [Internal]

Reviewed By: javache

Differential Revision: D43036612

fbshipit-source-id: fc70650bc4ba48d11f489556d1290ae9e7e58016

.babelrc

@@ -0,0 +1,8 @@
+{
+    "presets": [
+        "module:metro-react-native-babel-preset"
+    ],
+    "plugins": [
+        "babel-plugin-transform-flow-enums"
+    ]
+}

package.json

@@ -124,6 +124,7 @@
     "base64-js": "^1.1.2",
     "deprecated-react-native-prop-types": "^4.0.0",
     "event-target-shim": "^5.0.1",
+    "flow-enums-runtime": "^0.0.5",
     "invariant": "^2.2.4",
     "jest-environment-node": "^29.2.1",
     "jsc-android": "^250231.0.0",

packages/rn-tester/BUCK

@@ -75,6 +75,7 @@ rn_library(
     skip_processors = True,
     visibility = ["PUBLIC"],
     deps = [
+        "//xplat/js:node_modules__flow_19enums_19runtime",
         "//xplat/js:node_modules__nullthrows",
         "//xplat/js/RKJSModules/Libraries/Core:Core",
         "//xplat/js/RKJSModules/vendor/react:react",

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.cpp

@@ -33,7 +33,7 @@ ConstantsStruct NativeCxxModuleExample::getConstants(jsi::Runtime &rt) {
   return ConstantsStruct{true, 69, "react-native"};
 }
 
-int32_t NativeCxxModuleExample::getEnum(jsi::Runtime &rt, int32_t arg) {
+EnumInt NativeCxxModuleExample::getEnum(jsi::Runtime &rt, EnumInt arg) {
   return arg;
 }
 

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.h

@@ -53,6 +53,26 @@ struct Bridging<ValueStruct> : NativeCxxModuleExampleCxxBaseValueStructBridging<
                                    std::string,
                                    ObjectStruct> {};
 
+#pragma mark - enums
+enum EnumInt { A = 23, B = 42 };
+
+template <>
+struct Bridging<EnumInt> {
+  static EnumInt fromJs(jsi::Runtime &rt, int32_t value) {
+    if (value == 23) {
+      return EnumInt::A;
+    } else if (value == 42) {
+      return EnumInt::B;
+    } else {
+      throw jsi::JSError(rt, "Invalid enum value");
+    }
+  }
+
+  static jsi::Value toJs(jsi::Runtime &rt, EnumInt value) {
+    return bridging::toJs(rt, static_cast<int32_t>(value));
+  }
+};
+
 #pragma mark - implementation
 class NativeCxxModuleExample
     : public NativeCxxModuleExampleCxxSpec<NativeCxxModuleExample> {
@@ -71,7 +91,7 @@ class NativeCxxModuleExample
 
   ConstantsStruct getConstants(jsi::Runtime &rt);
 
-  int32_t getEnum(jsi::Runtime &rt, int32_t arg);
+  EnumInt getEnum(jsi::Runtime &rt, EnumInt arg);
 
   std::map<std::string, std::optional<int32_t>> getMap(
       jsi::Runtime &rt,

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.js

@@ -12,12 +12,10 @@ import type {TurboModule} from 'react-native/Libraries/TurboModule/RCTExport';
 
 import {TurboModuleRegistry} from 'react-native';
 
-/** FIXME: Enable flow-enum support
 export enum EnumInt {
   A = 23,
   B = 42,
 }
-*/
 
 export type UnionFloat = 1.44 | 2.88 | 5.76;
 export type UnionString = 'One' | 'Two' | 'Three';
@@ -45,8 +43,7 @@ export interface Spec extends TurboModule {
   +getArray: (arg: Array<ObjectStruct | null>) => Array<ObjectStruct | null>;
   +getBool: (arg: boolean) => boolean;
   +getConstants: () => ConstantsStruct;
-  // FIXME: Enable flow-enum support
-  +getEnum: (arg: number /*EnumInt*/) => number /*EnumInt*/;
+  +getEnum: (arg: EnumInt) => EnumInt;
   +getMap: (arg: {[key: string]: ?number}) => {[key: string]: ?number};
   +getNumber: (arg: number) => number;
   +getObject: (arg: ObjectStruct) => ObjectStruct;

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

@@ -20,7 +20,9 @@ import {
   RootTagContext,
 } from 'react-native';
 import * as React from 'react';
-import NativeCxxModuleExample /*EnumInt,*/ from '../../../NativeCxxModuleExample/NativeCxxModuleExample';
+import NativeCxxModuleExample, {
+  EnumInt,
+} from '../../../NativeCxxModuleExample/NativeCxxModuleExample';
 
 type State = {|
   testResults: {
@@ -72,7 +74,7 @@ class NativeCxxModuleExampleExample extends React.Component<{||}, State> {
       ]),
     getBool: () => NativeCxxModuleExample?.getBool(true),
     getConstants: () => NativeCxxModuleExample?.getConstants(),
-    getEnum: () => NativeCxxModuleExample?.getEnum(/*EnumInt.A*/ 2),
+    getEnum: () => NativeCxxModuleExample?.getEnum(EnumInt.A),
     getMap: () => NativeCxxModuleExample?.getMap({a: 1, b: null, c: 3}),
     getNumber: () => NativeCxxModuleExample?.getNumber(99.95),
     getObject: () =>

packages/rn-tester/package.json

@@ -21,13 +21,15 @@
   },
   "dependencies": {
     "invariant": "^2.2.4",
-    "nullthrows": "^1.1.1"
+    "nullthrows": "^1.1.1",
+    "flow-enums-runtime": "^0.0.5"
   },
   "peerDependencies": {
     "react": "18.2.0",
     "react-native": "*"
   },
   "devDependencies": {
+    "babel-plugin-transform-flow-enums":"^0.0.2",
     "connect": "^3.6.5",
     "ws": "^6.2.2"
   },

yarn.lock

@@ -494,7 +494,7 @@
   dependencies:
     "@babel/helper-plugin-utils" "^7.8.3"
 
-"@babel/plugin-syntax-flow@^7.0.0", "@babel/plugin-syntax-flow@^7.18.6", "@babel/plugin-syntax-flow@^7.2.0":
+"@babel/plugin-syntax-flow@^7.0.0", "@babel/plugin-syntax-flow@^7.12.1", "@babel/plugin-syntax-flow@^7.18.6", "@babel/plugin-syntax-flow@^7.2.0":
   version "7.18.6"
   resolved "https://registry.yarnpkg.com/@babel/plugin-syntax-flow/-/plugin-syntax-flow-7.18.6.tgz#774d825256f2379d06139be0c723c4dd444f3ca1"
   integrity sha512-LUbR+KNTBWCUAqRG9ex5Gnzu2IOkt8jRJbHHXFT9q+L9zm7M/QQbEqXyw1n1pohYvOyWC8CjeyjrSaIwiYjK7A==
@@ -2951,6 +2951,13 @@ babel-plugin-syntax-trailing-function-commas@^7.0.0-beta.0:
   resolved "https://registry.yarnpkg.com/babel-plugin-syntax-trailing-function-commas/-/babel-plugin-syntax-trailing-function-commas-7.0.0-beta.0.tgz#aa213c1435e2bffeb6fca842287ef534ad05d5cf"
   integrity sha512-Xj9XuRuz3nTSbaTXWv3itLOcxyF4oPD8douBBmj7U9BBC6nEBYfyOJYQMf/8PJAFotC62UY5dFfIGEPr7WswzQ==
 
+babel-plugin-transform-flow-enums@^0.0.2:
+  version "0.0.2"
+  resolved "https://registry.yarnpkg.com/babel-plugin-transform-flow-enums/-/babel-plugin-transform-flow-enums-0.0.2.tgz#d1d0cc9bdc799c850ca110d0ddc9f21b9ec3ef25"
+  integrity sha512-g4aaCrDDOsWjbm0PUUeVnkcVd6AKJsVc/MbnPhEotEpkeJQP6b8nzewohQi7+QS8UyPehOhGWn0nOwjvWpmMvQ==
+  dependencies:
+    "@babel/plugin-syntax-flow" "^7.12.1"
+
 babel-preset-current-node-syntax@^1.0.0:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/babel-preset-current-node-syntax/-/babel-preset-current-node-syntax-1.0.1.tgz#b4399239b89b2a011f9ddbe3e4f401fc40cff73b"
@@ -4404,6 +4411,11 @@ flow-bin@^0.199.1:
   resolved "https://registry.yarnpkg.com/flow-bin/-/flow-bin-0.199.1.tgz#678eac2303fa898227f4d103264b6ce49f4430c1"
   integrity sha512-Ic0Mp9iZ2exbH0mNj/XhzUWPZa9JylHb6uQARZnnYCTRwumOpjNOP0qwyRTltWrbCpfHjnWngNO9VLaVKHz2aQ==
 
+flow-enums-runtime@^0.0.5:
+  version "0.0.5"
+  resolved "https://registry.yarnpkg.com/flow-enums-runtime/-/flow-enums-runtime-0.0.5.tgz#95884bfcc82edaf27eef7e1dd09732331cfbafbc"
+  integrity sha512-PSZF9ZuaZD03sT9YaIs0FrGJ7lSUw7rHZIex+73UYVXg46eL/wxN5PaVcPJFudE2cJu5f0fezitV5aBkLHPUOQ==
+
 flow-parser@0.*, flow-parser@^0.185.0:
   version "0.185.0"
   resolved "https://registry.yarnpkg.com/flow-parser/-/flow-parser-0.185.0.tgz#56bde60805bad19b2934ebfc50c9485e5c5424f9"