From 642695615f55e750af23eec1d9a4613fa882a527 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Mon, 30 Mar 2020 09:50:04 -0700
Subject: [PATCH 1/9] Start project to codegen NM2 from spec files

---
 .../MyNativeModule.js                         |  32 ++++
 .../index.windows.js                          |   5 +
 .../SampleLibraryCPP/MyNativeModule.g.h       |  31 ++++
 .../windows/SampleLibraryCPP/MyNativeModule.h |  40 +++++
 .../SampleLibraryCPP/ReactPackageProvider.cpp |   3 +
 .../react-native-windows-codegen/.gitignore   |   2 +
 .../react-native-windows-codegen/README.md    |   7 +
 packages/react-native-windows-codegen/bin.js  |  12 ++
 .../react-native-windows-codegen/just-task.js |  20 +++
 .../react-native-windows-codegen/package.json |  34 ++++
 .../react-native-windows-codegen/src/Cli.ts   | 129 +++++++++++++++
 .../src/generators/GenerateNM2.ts             | 147 ++++++++++++++++++
 .../tsconfig.json                             |  15 ++
 yarn.lock                                     |  18 ++-
 14 files changed, 493 insertions(+), 2 deletions(-)
 create mode 100644 packages/microsoft-reactnative-sampleapps/MyNativeModule.js
 create mode 100644 packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h
 create mode 100644 packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.h
 create mode 100644 packages/react-native-windows-codegen/.gitignore
 create mode 100644 packages/react-native-windows-codegen/README.md
 create mode 100644 packages/react-native-windows-codegen/bin.js
 create mode 100644 packages/react-native-windows-codegen/just-task.js
 create mode 100644 packages/react-native-windows-codegen/package.json
 create mode 100644 packages/react-native-windows-codegen/src/Cli.ts
 create mode 100644 packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
 create mode 100644 packages/react-native-windows-codegen/tsconfig.json

diff --git a/packages/microsoft-reactnative-sampleapps/MyNativeModule.js b/packages/microsoft-reactnative-sampleapps/MyNativeModule.js
new file mode 100644
index 00000000000..eff7050bba2
--- /dev/null
+++ b/packages/microsoft-reactnative-sampleapps/MyNativeModule.js
@@ -0,0 +1,32 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ * Licensed under the MIT License.
+ *
+ * @flow
+ * @format
+ */
+
+'use strict';
+
+import type {TurboModule} from 'react-native/Libraries/TurboModule/RCTExport';
+import * as TurboModuleRegistry from 'react-native/Libraries/TurboModule/TurboModuleRegistry';
+
+export interface Spec extends TurboModule {
+  // Exported methods.
+  +getConstants: () => {|
+    const1: boolean,
+    const2: number,
+    const3: string,
+  |};
+  +voidFunc: () => void;
+  +getBool: (arg: boolean) => boolean;
+  +getNumber: (arg: number) => number;
+  +getString: (arg: string) => string;
+  // +getArray: (arg: Array<any>) => Array<any>;
+  // +getObject: (arg: Object) => Object;
+  // +getValue: (x: number, y: string, z: Object) => Object;
+  // +getValueWithCallback: (callback: (value: string) => void) => void;
+  // +getValueWithPromise: (error: boolean) => Promise<string>;
+}
+
+export default (TurboModuleRegistry.getEnforcing<Spec>('MyNativeModule'): Spec);
diff --git a/packages/microsoft-reactnative-sampleapps/index.windows.js b/packages/microsoft-reactnative-sampleapps/index.windows.js
index 8256f7c6253..5a271e0cc9b 100644
--- a/packages/microsoft-reactnative-sampleapps/index.windows.js
+++ b/packages/microsoft-reactnative-sampleapps/index.windows.js
@@ -14,12 +14,15 @@ import {
   UIManager,
   View,
   Linking,
+  Alert,
 } from 'react-native';
 
 import { NativeModules, NativeEventEmitter } from 'react-native';
 
 import {MyComp} from './myComp';
 
+import {default as MyNativeModule} from './MyNativeModule';
+
 // Creating event emitters
 const SampleModuleCSEmitter = new NativeEventEmitter(NativeModules.SampleModuleCS);
 const SampleModuleCppEmitter = new NativeEventEmitter(NativeModules.SampleModuleCpp);
@@ -278,6 +281,8 @@ class SampleApp extends Component {
           This app consumes custom Native Modules and View Managers.
         </Text>
 
+        <Button onPress={() => { Alert(MyNativeModule.getBool(true)); }} />
+
         <Button onPress={() => { this.onPressSampleModuleCS(); }} title="Call SampleModuleCS!" disabled={NativeModules.SampleModuleCS == null} />
         <Button onPress={() => { this.onPressSampleModuleCpp(); }} title="Call SampleModuleCpp!" disabled={NativeModules.SampleModuleCpp == null} />
 
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h
new file mode 100644
index 00000000000..51f8de1d2b6
--- /dev/null
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h
@@ -0,0 +1,31 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+// TODO: This file should be generated from the spec file
+
+#pragma once
+
+#include "NativeModules.h"
+#include "MyNativeModule.h"
+
+namespace SampleLibraryCpp {
+
+void RegisterModule(ReactModuleBuilder<MyNativeModule> &moduleBuilder) noexcept {
+  moduleBuilder.RegisterModuleName(L"MyNativeModule");
+  moduleBuilder.RegisterInitMethod(&MyNativeModule::Initialize);
+  moduleBuilder.RegisterConstant/*<bool>*/(&MyNativeModule::const1, L"const1");
+  moduleBuilder.RegisterConstant/*<number>*/(&MyNativeModule::const2, L"const2");
+  moduleBuilder.RegisterConstant/*<string>*/(&MyNativeModule::const3, L"const3");
+  moduleBuilder.RegisterMethod/*<void()>*/(&MyNativeModule::voidFunc, L"voidFunc");
+  moduleBuilder.RegisterMethod/*<bool(bool)>*/(&MyNativeModule::getBool, L"getBool");
+  moduleBuilder.RegisterMethod/*<number(number)>*/(&MyNativeModule::getNumber, L"getNumber");
+  moduleBuilder.RegisterMethod/*<string(string)>*/(&MyNativeModule::getString, L"getString");
+
+//  moduleBuilder.RegisterMethod/*<Array<any>(Array<any>)>*/(&MyNativeModule::getArray, L"getArray");
+//  moduleBuilder.RegisterMethod/*<Object(Object)>*/(&MyNativeModule::getObject, L"getObject");
+//  moduleBuilder.RegisterMethod/*<Object(number, string, Object)>*/(&MyNativeModule::getValue, L"getValue");
+//  moduleBuilder.RegisterMethod/*<void(callback)>*/(&MyNativeModule::getValueWithCallback, L"getValueWithCallback");
+//  moduleBuilder.RegisterMethod/*<promise(bool)>*/(&MyNativeModule::getValueWithPromise, L"getValueWithPromise");
+}
+
+} // namespace SampleLibraryCpp
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.h b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.h
new file mode 100644
index 00000000000..e2ad8fd99d7
--- /dev/null
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.h
@@ -0,0 +1,40 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+#pragma once
+
+#include "DebugHelpers.h"
+
+#define DEBUG_OUTPUT(...) DebugWriteLine("SampleModuleCppImpl", ##__VA_ARGS__);
+
+namespace SampleLibraryCpp {
+
+struct MyNativeModule {
+    void Initialize(IReactContext const & /*reactContext*/) noexcept {
+    }
+
+    const bool const1 = false;
+    const double const2 = 1.234;
+    const std::string const3 = "abc";
+
+    void voidFunc() noexcept {
+      DEBUG_OUTPUT("voidFunc");
+    }
+
+    bool getBool(bool arg) noexcept {
+      DEBUG_OUTPUT("getBool", arg);
+      return arg;
+    }
+
+    double getNumber(double arg) noexcept {
+      DEBUG_OUTPUT("getNumber", arg);
+      return arg;
+    }
+
+    std::string getString(std::string arg) noexcept {
+      DEBUG_OUTPUT("getString", arg);
+      return arg;
+    }
+};
+
+} // namespace SampleLibraryCpp
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
index ec971e59149..7c44ad797b2 100644
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
@@ -11,6 +11,9 @@
 #include "CustomUserControlViewManagerCpp.h"
 #include "SampleModuleCpp.h"
 
+// Not sure how the registration of this module should be..
+#include "MyNativeModule.g.h"
+
 using namespace winrt::Microsoft::ReactNative;
 
 namespace winrt::SampleLibraryCpp::implementation {
diff --git a/packages/react-native-windows-codegen/.gitignore b/packages/react-native-windows-codegen/.gitignore
new file mode 100644
index 00000000000..f42efbb9f7c
--- /dev/null
+++ b/packages/react-native-windows-codegen/.gitignore
@@ -0,0 +1,2 @@
+lib/
+lib-commonjs/
diff --git a/packages/react-native-windows-codegen/README.md b/packages/react-native-windows-codegen/README.md
new file mode 100644
index 00000000000..2950bcd0969
--- /dev/null
+++ b/packages/react-native-windows-codegen/README.md
@@ -0,0 +1,7 @@
+# react-native-windows-codegen
+
+Generators for react-native-codegen targeting react-native-windows
+
+## Usage
+
+Coming soon..
diff --git a/packages/react-native-windows-codegen/bin.js b/packages/react-native-windows-codegen/bin.js
new file mode 100644
index 00000000000..24e308197b6
--- /dev/null
+++ b/packages/react-native-windows-codegen/bin.js
@@ -0,0 +1,12 @@
+#!/usr/bin/env node
+
+/**
+ * Copyright (c) Microsoft Corporation.
+ * Licensed under the MIT License.
+ *
+ * @format
+ */
+
+// Yarn will fail to link workspace binaries if they haven't been built yet. Add
+// a simple JS file to forward to the CLI which is built after install.
+require('./lib-commonjs/Cli');
diff --git a/packages/react-native-windows-codegen/just-task.js b/packages/react-native-windows-codegen/just-task.js
new file mode 100644
index 00000000000..f5fac08c7f8
--- /dev/null
+++ b/packages/react-native-windows-codegen/just-task.js
@@ -0,0 +1,20 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ * Licensed under the MIT License.
+ *
+ * @format
+ * @ts-check
+ */
+
+const {eslintTask, series, task, taskPresets} = require('just-scripts');
+
+taskPresets.lib();
+
+task('eslint', () => {
+  return eslintTask();
+});
+task('eslint:fix', () => {
+  return eslintTask({fix: true});
+});
+task('lint', series('eslint'));
+task('lint:fix', series('eslint:fix'));
diff --git a/packages/react-native-windows-codegen/package.json b/packages/react-native-windows-codegen/package.json
new file mode 100644
index 00000000000..97c6b89da35
--- /dev/null
+++ b/packages/react-native-windows-codegen/package.json
@@ -0,0 +1,34 @@
+{
+  "name": "react-native-windows-codegen",
+  "version": "0.1.1",
+  "description": "Generators for react-native-codegen targeting react-native-windows",
+  "main": "index.js",
+  "repository": "https://github.com/microsoft/react-native-windows",
+  "license": "MIT",
+  "private": false,
+  "scripts": {
+    "build": "just-scripts build",
+    "clean": "just-scripts clean",
+    "lint": "just-scripts lint",
+    "lint:fix": "just-scripts lint:fix"
+  },
+  "bin": {
+    "react-native-windows-codegen": "./bin.js"
+  },
+  "dependencies": {
+    "chalk": "^3",
+    "react-native-tscodegen": "0.0.10",
+    "yargs": "^15.1.0"
+  },
+  "devDependencies": {
+    "@types/chalk": "^2.2.0",
+    "@types/yargs": "^15.0.3",
+    "just-scripts": "^0.36.1"
+  },
+  "files": [
+    "bin.js",
+    "lib-commonjs",
+    "README.md",
+    "react-native-codegen/src"
+  ]
+}
diff --git a/packages/react-native-windows-codegen/src/Cli.ts b/packages/react-native-windows-codegen/src/Cli.ts
new file mode 100644
index 00000000000..6476b876edb
--- /dev/null
+++ b/packages/react-native-windows-codegen/src/Cli.ts
@@ -0,0 +1,129 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ * Licensed under the MIT License.
+ *
+ * @format
+ */
+
+import * as yargs from 'yargs';
+import * as path from 'path';
+import * as fs from 'fs';
+import {generate as generateNM2} from './generators/GenerateNM2';
+// @ts-ignore
+import {parseFile} from 'react-native-tscodegen/lib/rncodegen/src/parsers/flow/modules';
+
+const schemaValidator = require('./react-native-codegen/src/SchemaValidator.js');
+
+const argv = yargs.options({
+  file: {
+    type: 'string',
+    describe: 'file which contains spec',
+  },
+}).argv;
+
+import {SchemaType} from 'react-native-tscodegen';
+
+interface Options {
+  libraryName: string;
+  schema: SchemaType;
+  outputDirectory: string;
+  moduleSpecName: string;
+}
+
+interface Config {
+  generators: any[] /*Generators[]*/;
+  test?: boolean;
+}
+
+/*
+const GENERATORS = {
+  descriptors: [generateComponentDescriptorH.generate],
+  events: [
+    generateEventEmitterCpp.generate,
+    generateEventEmitterH.generate,
+    generateModuleHObjCpp.generate,
+    generateModuleMm.generate,
+  ],
+  props: [
+    generateComponentHObjCpp.generate,
+    generatePropsCpp.generate,
+    generatePropsH.generate,
+    generatePropsJavaInterface.generate,
+    generatePropsJavaDelegate.generate,
+  ],
+  modules: [generateModuleCpp.generate, generateModuleH.generate],
+  tests: [generateTests.generate],
+  'shadow-nodes': [
+    generateShadowNodeCpp.generate,
+    generateShadowNodeH.generate,
+  ],
+};
+*/
+
+function checkFilesForChanges(
+  map: Map<string, string>,
+  outputDir: string,
+): boolean {
+  let hasChanged = false;
+
+  map.forEach((contents: string, fileName: string) => {
+    const location = path.join(outputDir, fileName);
+    const currentContents = fs.readFileSync(location, 'utf8');
+    if (currentContents !== contents) {
+      console.error(`- ${fileName} has changed`);
+
+      hasChanged = true;
+    }
+  });
+
+  return !hasChanged;
+}
+
+function writeMapToFiles(map: Map<string, string>, outputDir: string) {
+  let success = true;
+  map.forEach((contents: string, fileName: string) => {
+    try {
+      const location = path.join(outputDir, fileName);
+      fs.writeFileSync(location, contents);
+    } catch (error) {
+      success = false;
+      console.error(`Failed to write ${fileName} to ${outputDir}`, error);
+    }
+  });
+
+  return success;
+}
+
+function generate(
+  {libraryName, schema, outputDirectory, moduleSpecName}: Options,
+  {/*generators,*/ test}: Config,
+): boolean {
+  schemaValidator.validate(schema);
+
+  const generatedFiles = [];
+  /*
+  for (const name of generators) {
+    for (const generator of GENERATORS[name]) {
+      generatedFiles.push(...generator(libraryName, schema, moduleSpecName));
+    }
+  }
+*/
+  generatedFiles.push(...generateNM2(libraryName, schema, moduleSpecName));
+
+  const filesToUpdate = new Map<string, string>([...generatedFiles]);
+
+  if (test === true) {
+    return checkFilesForChanges(filesToUpdate, outputDirectory);
+  }
+
+  return writeMapToFiles(filesToUpdate, outputDirectory);
+}
+
+const schema: SchemaType = parseFile(argv.file);
+const libraryName = 'libraryName';
+const moduleSpecName = 'moduleSpecName';
+const outputDirectory = 'codegen-out-dir';
+generate(
+  {libraryName, schema, outputDirectory, moduleSpecName},
+  {generators: [], test: true},
+);
diff --git a/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
new file mode 100644
index 00000000000..8ddda953a31
--- /dev/null
+++ b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
@@ -0,0 +1,147 @@
+/**
+ * Copyright (c) Microsoft Corporation.
+ * Licensed under the MIT License.
+ */
+
+'use strict';
+
+import {
+  SchemaType,
+  FunctionTypeAnnotationParamTypeAnnotation,
+  FunctionTypeAnnotationReturn,
+} from 'react-native-tscodegen';
+
+type FilesOutput = Map<string, string>;
+
+const moduleTemplate = `
+class JSI_EXPORT Native::_MODULE_NAME_::CxxSpecJSI : public TurboModule {
+protected:
+  Native::_MODULE_NAME_::CxxSpecJSI(std::shared_ptr<CallInvoker> jsInvoker);
+
+public:
+::_MODULE_PROPERTIES_::
+
+};`;
+
+const template = `
+/**
+ * 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 <ReactCommon/TurboModule.h>
+
+namespace facebook {
+namespace react {
+::_MODULES_::
+
+} // namespace react
+} // namespace facebook
+`;
+
+function translatePrimitiveJSTypeToCpp(
+  type:
+    | FunctionTypeAnnotationParamTypeAnnotation
+    | FunctionTypeAnnotationReturn,
+  error: string,
+) {
+  switch (type.type) {
+    case 'VoidTypeAnnotation':
+      return 'void';
+    case 'StringTypeAnnotation':
+      return 'jsi::String';
+    case 'NumberTypeAnnotation':
+    case 'FloatTypeAnnotation':
+      return 'double';
+    case 'Int32TypeAnnotation':
+      return 'int';
+    case 'BooleanTypeAnnotation':
+      return 'bool';
+    case 'GenericObjectTypeAnnotation':
+    case 'ObjectTypeAnnotation':
+      return 'jsi::Object';
+    case 'ArrayTypeAnnotation':
+      return 'jsi::Array';
+    case 'FunctionTypeAnnotation':
+      return 'jsi::Function';
+    case 'GenericPromiseTypeAnnotation':
+      return 'jsi::Value';
+
+    default:
+      throw new Error(error);
+  }
+}
+const propertyTemplate =
+  'virtual ::_RETURN_VALUE_:: ::_PROPERTY_NAME_::(jsi::Runtime &rt::_ARGS_::) = 0;';
+
+export function generate(
+  libraryName: string,
+  schema: SchemaType,
+  moduleSpecName: string,
+): FilesOutput {
+  const nativeModules = Object.keys(schema.modules)
+    .map(moduleName => {
+      const modules = schema.modules[moduleName].nativeModules;
+      if (modules == null) {
+        return null;
+      }
+
+      return modules;
+    })
+    .filter(Boolean)
+    .reduce((acc, components) => Object.assign(acc, components), {});
+
+  const modules = Object.keys(nativeModules)
+    .map(name => {
+      const {properties} = nativeModules[name];
+      const traversedProperties = properties
+        .map(prop => {
+          const traversedArgs = prop.typeAnnotation.params
+            .map(param => {
+              const translatedParam = translatePrimitiveJSTypeToCpp(
+                param.typeAnnotation,
+                `Unspopported type for param "${param.name}" in ${
+                  prop.name
+                }. Found: ${param.typeAnnotation.type}`,
+              );
+              const isObject = translatedParam.startsWith('jsi::');
+              return (
+                (isObject
+                  ? 'const ' + translatedParam + ' &'
+                  : translatedParam + ' ') + param.name
+              );
+            })
+            .join(', ');
+          return propertyTemplate
+            .replace('::_PROPERTY_NAME_::', prop.name)
+            .replace(
+              '::_RETURN_VALUE_::',
+              translatePrimitiveJSTypeToCpp(
+                prop.typeAnnotation.returnTypeAnnotation,
+                `Unspopported return type for ${prop.name}. Found: ${
+                  prop.typeAnnotation.returnTypeAnnotation.type
+                }`,
+              ),
+            )
+            .replace(
+              '::_ARGS_::',
+              traversedArgs === '' ? '' : ', ' + traversedArgs,
+            );
+        })
+        .join('\n');
+      return moduleTemplate
+        .replace(/::_MODULE_PROPERTIES_::/g, traversedProperties)
+        .replace(/::_MODULE_NAME_::/g, name)
+        .replace('::_PROPERTIES_MAP_::', '');
+    })
+    .join('\n');
+
+  const fileName = 'NativeModules.h';
+  const replacedTemplate = template.replace(/::_MODULES_::/g, modules);
+
+  return new Map([[fileName, replacedTemplate]]);
+}
diff --git a/packages/react-native-windows-codegen/tsconfig.json b/packages/react-native-windows-codegen/tsconfig.json
new file mode 100644
index 00000000000..955be039942
--- /dev/null
+++ b/packages/react-native-windows-codegen/tsconfig.json
@@ -0,0 +1,15 @@
+{
+  "compilerOptions": {
+    "baseUrl": ".",
+    "target": "es6",
+    "sourceMap": true,
+    "noImplicitAny": true,
+    "preserveConstEnums": true,
+    "moduleResolution": "node",
+    "noUnusedLocals": true,
+    "skipLibCheck": true,
+    "rootDirs": ["src"],
+  },
+  "include": ["src"],
+  "exclude": ["node_modules"]
+}
diff --git a/yarn.lock b/yarn.lock
index 0bd4e1d829e..c9d317ea52b 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -8540,7 +8540,7 @@ jsc-android@^245459.0.0:
   resolved "https://registry.yarnpkg.com/jsc-android/-/jsc-android-245459.0.0.tgz#e584258dd0b04c9159a27fb104cd5d491fd202c9"
   integrity sha512-wkjURqwaB1daNkDi2OYYbsLnIdC/lUM2nPXQKRs5pqEU9chDg435bjvo+LSaHotDENygHQDHe+ntUkkw2gwMtg==
 
-jscodeshift@^0.6.2:
+jscodeshift@0.6.4, jscodeshift@^0.6.2:
   version "0.6.4"
   resolved "https://registry.yarnpkg.com/jscodeshift/-/jscodeshift-0.6.4.tgz#e19ab86214edac86a75c4557fc88b3937d558a8e"
   integrity sha512-+NF/tlNbc2WEhXUuc4WEJLsJumF84tnaMUZW2hyJw3jThKKRvsPX4sPJVgO1lPE28z0gNL+gwniLG9d8mYvQCQ==
@@ -10351,7 +10351,7 @@ npm-run-path@^2.0.0:
     gauge "~2.7.3"
     set-blocking "~2.0.0"
 
-nullthrows@^1.1.0:
+nullthrows@1.1.1, nullthrows@^1.1.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/nullthrows/-/nullthrows-1.1.1.tgz#7818258843856ae971eae4208ad7d7eb19a431b1"
   integrity sha512-2vPPEi+Z7WqML2jZYddDIfy5Dqb0r2fze2zTxNNknZaFpVHU3mFB3R+DWeJWGVx0ecvttSGlJTI+WG+8Z4cDWw==
@@ -11358,6 +11358,15 @@ react-is@^16.8.1, react-is@^16.8.4, react-is@^16.8.6:
   resolved "https://registry.yarnpkg.com/react-is/-/react-is-16.9.0.tgz#21ca9561399aad0ff1a7701c01683e8ca981edcb"
   integrity sha512-tJBzzzIgnnRfEm046qRcURvwQnZVXmuCbscxUO5RWrGTXpon2d4c8mI0D8WE6ydVIm29JiLB6+RslkIvym9Rjw==
 
+react-native-tscodegen@0.0.10:
+  version "0.0.10"
+  resolved "https://registry.yarnpkg.com/react-native-tscodegen/-/react-native-tscodegen-0.0.10.tgz#2997f039625e55aac91a367ac3d6b496c50f1265"
+  integrity sha512-MwG76JC/YpelWgcOmPQIiYdIAL+4uwafFROVUMNHI1ko5LkSay1sY1D7FDdAq9fXE0kZoHna7YHD50DR6CLj8w==
+  dependencies:
+    jscodeshift "0.6.4"
+    nullthrows "1.1.1"
+    typescript "^3.5.3"
+
 react-native@0.61.5:
   version "0.61.5"
   resolved "https://registry.yarnpkg.com/react-native/-/react-native-0.61.5.tgz#6e21acb56cbd75a3baeb1f70201a66f42600bba8"
@@ -13278,6 +13287,11 @@ typescript@^3.5.1, typescript@~3.7.2:
   resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.7.2.tgz#27e489b95fa5909445e9fef5ee48d81697ad18fb"
   integrity sha512-ml7V7JfiN2Xwvcer+XAf2csGO1bPBdRbFCkYBczNZggrBZ9c7G3riSUeJmqEU5uOtXNPMhE3n+R4FA/3YOAWOQ==
 
+typescript@^3.5.3:
+  version "3.8.3"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.8.3.tgz#409eb8544ea0335711205869ec458ab109ee1061"
+  integrity sha512-MYlEfn5VrLNsgudQTVJeNaQFUAI7DkhnOjdpAp4T+ku1TfQClewlbSuTVHiA+8skNBgaf02TL/kLOvig4y3G8w==
+
 typical@^2.6.1:
   version "2.6.1"
   resolved "https://registry.yarnpkg.com/typical/-/typical-2.6.1.tgz#5c080e5d661cbbe38259d2e70a3c7253e873881d"

From baee0f67b4d9cb12a370c3b06b7b32eb82fa5d2f Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Tue, 31 Mar 2020 09:16:29 -0700
Subject: [PATCH 2/9] Basic codegen working.

---
 .../{MyNativeModule.js => NativeMyModule.js}  |   4 +-
 .../codegen/NativeModules.g.h                 |  66 +++++++
 .../index.windows.js                          |   4 +-
 .../package.json                              |   2 +
 .../{MyNativeModule.h => MyModule.h}          |  12 +-
 .../SampleLibraryCPP/MyNativeModule.g.h       |  31 ---
 .../SampleLibraryCPP/ReactPackageProvider.cpp |  16 +-
 .../react-native-windows-codegen/package.json |   2 +-
 .../react-native-windows-codegen/src/Cli.ts   |  35 ++--
 .../src/generators/GenerateNM2.ts             | 176 +++++++++++-------
 10 files changed, 228 insertions(+), 120 deletions(-)
 rename packages/microsoft-reactnative-sampleapps/{MyNativeModule.js => NativeMyModule.js} (91%)
 create mode 100644 packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
 rename packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/{MyNativeModule.h => MyModule.h} (69%)
 delete mode 100644 packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h

diff --git a/packages/microsoft-reactnative-sampleapps/MyNativeModule.js b/packages/microsoft-reactnative-sampleapps/NativeMyModule.js
similarity index 91%
rename from packages/microsoft-reactnative-sampleapps/MyNativeModule.js
rename to packages/microsoft-reactnative-sampleapps/NativeMyModule.js
index eff7050bba2..1663d29a2eb 100644
--- a/packages/microsoft-reactnative-sampleapps/MyNativeModule.js
+++ b/packages/microsoft-reactnative-sampleapps/NativeMyModule.js
@@ -13,11 +13,13 @@ import * as TurboModuleRegistry from 'react-native/Libraries/TurboModule/TurboMo
 
 export interface Spec extends TurboModule {
   // Exported methods.
+  /*
   +getConstants: () => {|
     const1: boolean,
     const2: number,
     const3: string,
   |};
+  */
   +voidFunc: () => void;
   +getBool: (arg: boolean) => boolean;
   +getNumber: (arg: number) => number;
@@ -29,4 +31,4 @@ export interface Spec extends TurboModule {
   // +getValueWithPromise: (error: boolean) => Promise<string>;
 }
 
-export default (TurboModuleRegistry.getEnforcing<Spec>('MyNativeModule'): Spec);
+export default (TurboModuleRegistry.getEnforcing<Spec>('MyModule'): Spec);
diff --git a/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h b/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
new file mode 100644
index 00000000000..82325392c59
--- /dev/null
+++ b/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
@@ -0,0 +1,66 @@
+
+/**
+ * This file is auto-generated from a TurboModule Spec file
+ */
+
+#pragma once
+
+#include "NativeModules.h"
+
+namespace SampleLibraryCpp {
+
+/*
+ * This function registers a class as implementing a TurboModule Spec
+ * The class must implement all the methods as required by the Spec.
+ * Methods may be implemented using one of the method signatures provided above the RegisterMethod calls
+ *
+ * Note that methods can be optionally written using a veriety of method signatures which may be preferable
+ * depending on your scenario.
+ * 
+ * An example implementation you could copy/paste is provided here:
+
+class MyModule {
+  void Initialize() {
+  }
+
+  void MyModule::voidFunc() noexcept {
+    throw std::logic_error("MyModule::voidFunc not yet implemented.");
+  }
+
+  bool MyModule::getBool(bool) noexcept {
+    throw std::logic_error("MyModule::getBool not yet implemented.");
+  }
+
+  double MyModule::getNumber(double) noexcept {
+    throw std::logic_error("MyModule::getNumber not yet implemented.");
+  }
+
+  std::string MyModule::getString(std::string) noexcept {
+    throw std::logic_error("MyModule::getString not yet implemented.");
+  }
+};
+
+ */
+template <typename TMyModuleImpl>
+void RegisterMyModuleModule(ReactModuleBuilder<TMyModuleImpl> &moduleBuilder) noexcept {
+  moduleBuilder.RegisterModuleName(L"MyModule");
+  moduleBuilder.RegisterInitMethod(&TMyModuleImpl::Initialize);
+
+  // This method can be implemented using the following method signature:
+  // void TMyModuleImpl::voidFunc() noexcept;
+  moduleBuilder.RegisterMethod/*<void()>*/(&TMyModuleImpl::voidFunc, L"voidFunc");
+
+  // This method can be implemented using the following method signature:
+  // bool TMyModuleImpl::getBool(bool) noexcept;
+  moduleBuilder.RegisterSyncMethod/*<bool(bool)>*/(&TMyModuleImpl::getBool, L"getBool");
+
+  // This method can be implemented using the following method signature:
+  // double TMyModuleImpl::getNumber(double) noexcept;
+  moduleBuilder.RegisterSyncMethod/*<double(double)>*/(&TMyModuleImpl::getNumber, L"getNumber");
+
+  // This method can be implemented using the following method signature:
+  // std::string TMyModuleImpl::getString(std::string) noexcept;
+  moduleBuilder.RegisterSyncMethod/*<std::string(std::string)>*/(&TMyModuleImpl::getString, L"getString");
+}
+
+} // namespace SampleLibraryCpp
diff --git a/packages/microsoft-reactnative-sampleapps/index.windows.js b/packages/microsoft-reactnative-sampleapps/index.windows.js
index 5a271e0cc9b..3da9c211313 100644
--- a/packages/microsoft-reactnative-sampleapps/index.windows.js
+++ b/packages/microsoft-reactnative-sampleapps/index.windows.js
@@ -21,7 +21,7 @@ import { NativeModules, NativeEventEmitter } from 'react-native';
 
 import {MyComp} from './myComp';
 
-import {default as MyNativeModule} from './MyNativeModule';
+import {default as MyModule} from './NativeMyModule';
 
 // Creating event emitters
 const SampleModuleCSEmitter = new NativeEventEmitter(NativeModules.SampleModuleCS);
@@ -281,7 +281,7 @@ class SampleApp extends Component {
           This app consumes custom Native Modules and View Managers.
         </Text>
 
-        <Button onPress={() => { Alert(MyNativeModule.getBool(true)); }} />
+        <Button onPress={() => { MyModule.voidFunc(); }} title="Call MyModule tests"/>
 
         <Button onPress={() => { this.onPressSampleModuleCS(); }} title="Call SampleModuleCS!" disabled={NativeModules.SampleModuleCS == null} />
         <Button onPress={() => { this.onPressSampleModuleCpp(); }} title="Call SampleModuleCpp!" disabled={NativeModules.SampleModuleCpp == null} />
diff --git a/packages/microsoft-reactnative-sampleapps/package.json b/packages/microsoft-reactnative-sampleapps/package.json
index cf6e53d3a90..85edda2c0d8 100644
--- a/packages/microsoft-reactnative-sampleapps/package.json
+++ b/packages/microsoft-reactnative-sampleapps/package.json
@@ -7,6 +7,7 @@
     "bundle-cpp": "just-scripts prepareBundle && react-native bundle --platform windows --entry-file index.windows.js --bundle-output windows/SampleAppCpp/Bundle/index.windows.bundle --assets-dest windows/SampleAppCpp/Bundle",
     "bundle-cs": "just-scripts prepareBundle && react-native bundle --platform windows --entry-file index.windows.js --bundle-output windows/SampleAppCS/Bundle/index.windows.bundle --assets-dest windows/SampleAppCS/Bundle",
     "clean": "just-scripts clean",
+    "codegen": "react-native-windows-codegen --file NativeMyModule.js --namespace SampleLibraryCpp",
     "postinstall": "node postinstall.js",
     "start": "react-native start",
     "lint": "just-scripts lint",
@@ -26,6 +27,7 @@
     "@types/react-native": "~0.61.5",
     "just-scripts": "^0.36.1",
     "metro-react-native-babel-preset": "0.55.0",
+    "react-native-windows-codegen": "0.0.1",
     "react-test-renderer": "16.8.6"
   }
 }
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.h b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
similarity index 69%
rename from packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.h
rename to packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
index e2ad8fd99d7..f4ecad285aa 100644
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.h
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
@@ -5,11 +5,11 @@
 
 #include "DebugHelpers.h"
 
-#define DEBUG_OUTPUT(...) DebugWriteLine("SampleModuleCppImpl", ##__VA_ARGS__);
+#define DEBUG_MYMODULE_OUTPUT(...) DebugWriteLine("MyModule", ##__VA_ARGS__);
 
 namespace SampleLibraryCpp {
 
-struct MyNativeModule {
+struct MyModule {
     void Initialize(IReactContext const & /*reactContext*/) noexcept {
     }
 
@@ -18,21 +18,21 @@ struct MyNativeModule {
     const std::string const3 = "abc";
 
     void voidFunc() noexcept {
-      DEBUG_OUTPUT("voidFunc");
+      DEBUG_MYMODULE_OUTPUT("voidFunc");
     }
 
     bool getBool(bool arg) noexcept {
-      DEBUG_OUTPUT("getBool", arg);
+      DEBUG_MYMODULE_OUTPUT("getBool", arg);
       return arg;
     }
 
     double getNumber(double arg) noexcept {
-      DEBUG_OUTPUT("getNumber", arg);
+      DEBUG_MYMODULE_OUTPUT("getNumber", arg);
       return arg;
     }
 
     std::string getString(std::string arg) noexcept {
-      DEBUG_OUTPUT("getString", arg);
+      DEBUG_MYMODULE_OUTPUT("getString", arg);
       return arg;
     }
 };
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h
deleted file mode 100644
index 51f8de1d2b6..00000000000
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyNativeModule.g.h
+++ /dev/null
@@ -1,31 +0,0 @@
-// Copyright (c) Microsoft Corporation. All rights reserved.
-// Licensed under the MIT License.
-
-// TODO: This file should be generated from the spec file
-
-#pragma once
-
-#include "NativeModules.h"
-#include "MyNativeModule.h"
-
-namespace SampleLibraryCpp {
-
-void RegisterModule(ReactModuleBuilder<MyNativeModule> &moduleBuilder) noexcept {
-  moduleBuilder.RegisterModuleName(L"MyNativeModule");
-  moduleBuilder.RegisterInitMethod(&MyNativeModule::Initialize);
-  moduleBuilder.RegisterConstant/*<bool>*/(&MyNativeModule::const1, L"const1");
-  moduleBuilder.RegisterConstant/*<number>*/(&MyNativeModule::const2, L"const2");
-  moduleBuilder.RegisterConstant/*<string>*/(&MyNativeModule::const3, L"const3");
-  moduleBuilder.RegisterMethod/*<void()>*/(&MyNativeModule::voidFunc, L"voidFunc");
-  moduleBuilder.RegisterMethod/*<bool(bool)>*/(&MyNativeModule::getBool, L"getBool");
-  moduleBuilder.RegisterMethod/*<number(number)>*/(&MyNativeModule::getNumber, L"getNumber");
-  moduleBuilder.RegisterMethod/*<string(string)>*/(&MyNativeModule::getString, L"getString");
-
-//  moduleBuilder.RegisterMethod/*<Array<any>(Array<any>)>*/(&MyNativeModule::getArray, L"getArray");
-//  moduleBuilder.RegisterMethod/*<Object(Object)>*/(&MyNativeModule::getObject, L"getObject");
-//  moduleBuilder.RegisterMethod/*<Object(number, string, Object)>*/(&MyNativeModule::getValue, L"getValue");
-//  moduleBuilder.RegisterMethod/*<void(callback)>*/(&MyNativeModule::getValueWithCallback, L"getValueWithCallback");
-//  moduleBuilder.RegisterMethod/*<promise(bool)>*/(&MyNativeModule::getValueWithPromise, L"getValueWithPromise");
-}
-
-} // namespace SampleLibraryCpp
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
index 7c44ad797b2..0803c5502fa 100644
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
@@ -11,15 +11,27 @@
 #include "CustomUserControlViewManagerCpp.h"
 #include "SampleModuleCpp.h"
 
-// Not sure how the registration of this module should be..
-#include "MyNativeModule.g.h"
+// Import generated definitions
+#include "..\..\codegen\NativeModules.g.h"
+
+// Import impls of modules
+#include "MyModule.h"
 
 using namespace winrt::Microsoft::ReactNative;
 
+namespace SampleLibraryCpp {
+
+// Lame that we need this right now
+void RegisterModule(ReactModuleBuilder<::SampleLibraryCpp::MyModule> &moduleBuilder) {
+  RegisterMyModuleModule(moduleBuilder);
+}
+}
+
 namespace winrt::SampleLibraryCpp::implementation {
 
 void ReactPackageProvider::CreatePackage(IReactPackageBuilder const &packageBuilder) noexcept {
   AddAttributedModules(packageBuilder);
+  packageBuilder.AddModule(L"MyModule", MakeModuleProvider<::SampleLibraryCpp::MyModule>());
   packageBuilder.AddViewManager(
       L"CustomUserControlViewManagerCpp", []() { return winrt::make<CustomUserControlViewManagerCpp>(); });
   packageBuilder.AddViewManager(L"CircleViewManagerCpp", []() { return winrt::make<CircleViewManagerCpp>(); });
diff --git a/packages/react-native-windows-codegen/package.json b/packages/react-native-windows-codegen/package.json
index 97c6b89da35..680e0aaaf05 100644
--- a/packages/react-native-windows-codegen/package.json
+++ b/packages/react-native-windows-codegen/package.json
@@ -1,6 +1,6 @@
 {
   "name": "react-native-windows-codegen",
-  "version": "0.1.1",
+  "version": "0.0.1",
   "description": "Generators for react-native-codegen targeting react-native-windows",
   "main": "index.js",
   "repository": "https://github.com/microsoft/react-native-windows",
diff --git a/packages/react-native-windows-codegen/src/Cli.ts b/packages/react-native-windows-codegen/src/Cli.ts
index 6476b876edb..d8ea11a57dd 100644
--- a/packages/react-native-windows-codegen/src/Cli.ts
+++ b/packages/react-native-windows-codegen/src/Cli.ts
@@ -8,17 +8,26 @@
 import * as yargs from 'yargs';
 import * as path from 'path';
 import * as fs from 'fs';
-import {generate as generateNM2} from './generators/GenerateNM2';
+import {createNM2Generator} from './generators/GenerateNM2';
 // @ts-ignore
-import {parseFile} from 'react-native-tscodegen/lib/rncodegen/src/parsers/flow/modules';
-
-const schemaValidator = require('./react-native-codegen/src/SchemaValidator.js');
+import {parseFile} from 'react-native-tscodegen/lib/rncodegen/src/parsers/flow';
+// @ts-ignore
+import * as schemaValidator from 'react-native-tscodegen/lib/rncodegen/src/schemaValidator';
 
 const argv = yargs.options({
   file: {
     type: 'string',
     describe: 'file which contains spec',
   },
+  test: {
+    type: 'boolean',
+    describe: 'Verify that the generated output is unchanged',
+  },
+  namespace: {
+    type: 'string',
+    describe: 'C++/C# Namespace to put generated native modules in',
+    default: 'MyNamespace',
+  },
 }).argv;
 
 import {SchemaType} from 'react-native-tscodegen';
@@ -64,19 +73,20 @@ function checkFilesForChanges(
   map: Map<string, string>,
   outputDir: string,
 ): boolean {
-  let hasChanged = false;
-
   map.forEach((contents: string, fileName: string) => {
     const location = path.join(outputDir, fileName);
+    if (!fs.existsSync(location)) {
+      return true;
+    }
+
     const currentContents = fs.readFileSync(location, 'utf8');
     if (currentContents !== contents) {
       console.error(`- ${fileName} has changed`);
-
-      hasChanged = true;
+      return true;
     }
   });
 
-  return !hasChanged;
+  return false;
 }
 
 function writeMapToFiles(map: Map<string, string>, outputDir: string) {
@@ -108,6 +118,9 @@ function generate(
     }
   }
 */
+
+  const generateNM2 = createNM2Generator({namespace: argv.namespace});
+
   generatedFiles.push(...generateNM2(libraryName, schema, moduleSpecName));
 
   const filesToUpdate = new Map<string, string>([...generatedFiles]);
@@ -122,8 +135,8 @@ function generate(
 const schema: SchemaType = parseFile(argv.file);
 const libraryName = 'libraryName';
 const moduleSpecName = 'moduleSpecName';
-const outputDirectory = 'codegen-out-dir';
+const outputDirectory = 'codegen';
 generate(
   {libraryName, schema, outputDirectory, moduleSpecName},
-  {generators: [], test: true},
+  {generators: [], test: false},
 );
diff --git a/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
index 8ddda953a31..d78edb6a370 100644
--- a/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
+++ b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
@@ -7,6 +7,8 @@
 
 import {
   SchemaType,
+  MethodTypeShape,
+  //FunctionTypeAnnotationParam,
   FunctionTypeAnnotationParamTypeAnnotation,
   FunctionTypeAnnotationReturn,
 } from 'react-native-tscodegen';
@@ -14,46 +16,64 @@ import {
 type FilesOutput = Map<string, string>;
 
 const moduleTemplate = `
-class JSI_EXPORT Native::_MODULE_NAME_::CxxSpecJSI : public TurboModule {
-protected:
-  Native::_MODULE_NAME_::CxxSpecJSI(std::shared_ptr<CallInvoker> jsInvoker);
+/*
+ * This function registers a class as implementing a TurboModule Spec
+ * The class must implement all the methods as required by the Spec.
+ * Methods may be implemented using one of the method signatures provided above the RegisterMethod calls
+ *
+ * Note that methods can be optionally written using a veriety of method signatures which may be preferable
+ * depending on your scenario.
+ * 
+ * An example implementation you could copy/paste is provided here:
+
+class ::_MODULE_NAME_:: {
+  void Initialize() {
+  }
+::_EXAMPLE_MODULE_PROPERTIES_::
+};
 
-public:
+ */
+template <typename TMyModuleImpl>
+void Register::_MODULE_NAME_::Module(ReactModuleBuilder<::_MODULE_IMPL_NAME_::> &moduleBuilder) noexcept {
+  moduleBuilder.RegisterModuleName(L"::_MODULE_NAME_::");
+  moduleBuilder.RegisterInitMethod(&::_MODULE_IMPL_NAME_::::Initialize);
 ::_MODULE_PROPERTIES_::
+}`;
 
-};`;
+const moduleMethodTemplate = `
+  // This method can be implemented using the following method signature:
+  // ::_METHOD_RETURN_TYPE_:: ::_MODULE_IMPL_NAME_::::::_METHOD_NAME_::(::_METHOD_ARGS_::) noexcept;
+  moduleBuilder.Register::_METHOD_SYNC_::Method/*<::_METHOD_TYPE_::>*/(&::_MODULE_IMPL_NAME_::::::_METHOD_NAME_::, L"::_METHOD_NAME_::");`;
+
+const exampleMethodTemplate = `
+  ::_METHOD_RETURN_TYPE_:: ::_MODULE_NAME_::::::_METHOD_NAME_::(::_METHOD_ARGS_::) noexcept {
+    throw std::logic_error("::_MODULE_NAME_::::::_METHOD_NAME_:: not yet implemented.");
+  }`;
 
 const template = `
 /**
- * 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.
+ * This file is auto-generated from a TurboModule Spec file
  */
 
 #pragma once
 
-#include <ReactCommon/TurboModule.h>
+#include "NativeModules.h"
 
-namespace facebook {
-namespace react {
+namespace ::_NAMESPACE_:: {
 ::_MODULES_::
 
-} // namespace react
-} // namespace facebook
+} // namespace ::_NAMESPACE_::
 `;
 
 function translatePrimitiveJSTypeToCpp(
-  type:
-    | FunctionTypeAnnotationParamTypeAnnotation
-    | FunctionTypeAnnotationReturn,
+  type:    FunctionTypeAnnotationParamTypeAnnotation    | FunctionTypeAnnotationReturn,
   error: string,
 ) {
   switch (type.type) {
     case 'VoidTypeAnnotation':
       return 'void';
     case 'StringTypeAnnotation':
-      return 'jsi::String';
+      return 'std::string';
     case 'NumberTypeAnnotation':
     case 'FloatTypeAnnotation':
       return 'double';
@@ -64,25 +84,77 @@ function translatePrimitiveJSTypeToCpp(
     case 'GenericObjectTypeAnnotation':
     case 'ObjectTypeAnnotation':
       return 'jsi::Object';
+/*
     case 'ArrayTypeAnnotation':
       return 'jsi::Array';
     case 'FunctionTypeAnnotation':
       return 'jsi::Function';
     case 'GenericPromiseTypeAnnotation':
       return 'jsi::Value';
-
+*/
     default:
       throw new Error(error);
   }
 }
-const propertyTemplate =
-  'virtual ::_RETURN_VALUE_:: ::_PROPERTY_NAME_::(jsi::Runtime &rt::_ARGS_::) = 0;';
-
-export function generate(
-  libraryName: string,
-  schema: SchemaType,
-  moduleSpecName: string,
-): FilesOutput {
+
+function renderProperties(properties : ReadonlyArray<MethodTypeShape>, example : boolean) : string {
+  return properties
+  .map(prop => {
+
+    const isMethodSync = prop.typeAnnotation.returnTypeAnnotation.type !== 'VoidTypeAnnotation';
+
+    let params = prop.typeAnnotation.params;
+
+    /*
+    let hasCallback = false;
+    // If last arg is a callback
+    if (prop.typeAnnotation.returnTypeAnnotation.type === 'VoidTypeAnnotation' &&
+      params.length && params[params.length - 1].typeAnnotation.type === 'FunctionTypeAnnotation') {
+      hasCallback = true;
+    }
+    */
+
+    const traversedArgs = params
+      .map(param => {
+        const translatedParam = translatePrimitiveJSTypeToCpp(
+          param.typeAnnotation,
+          `Unspopported type for param "${param.name}" in ${
+            prop.name
+          }. Found: ${param.typeAnnotation.type}`,
+        );
+        return `${translatedParam}`;
+        /*
+        const isObject = translatedParam.startsWith('jsi::');
+        return (
+          (isObject
+            ? 'const ' + translatedParam + ' &'
+            : translatedParam + ' ') + param.name
+        );
+        */
+      })
+      .join(', ');
+
+    const translatedReturnParam = translatePrimitiveJSTypeToCpp(
+      prop.typeAnnotation.returnTypeAnnotation,
+      `Unsupported return type for ${prop.name}. Found: ${
+        prop.typeAnnotation.returnTypeAnnotation.type
+      }`);
+
+    return (example ? exampleMethodTemplate : moduleMethodTemplate)
+      .replace('::_METHOD_SYNC_::', isMethodSync ? 'Sync' : '')
+      .replace(/::_METHOD_NAME_::/g, prop.name)
+      .replace('::_METHOD_RETURN_TYPE_::', translatedReturnParam)
+      .replace('::_METHOD_ARGS_::', traversedArgs)
+      .replace('::_METHOD_TYPE_::', `${translatedReturnParam}(${traversedArgs})`);
+  })
+  .join('\n');
+}
+
+export function createNM2Generator({namespace} : {namespace: string}) {
+  return (  _libraryName: string,
+    schema: SchemaType,
+    _moduleSpecName: string) : FilesOutput => {
+
   const nativeModules = Object.keys(schema.modules)
     .map(moduleName => {
       const modules = schema.modules[moduleName].nativeModules;
@@ -95,53 +167,25 @@ export function generate(
     .filter(Boolean)
     .reduce((acc, components) => Object.assign(acc, components), {});
 
+
   const modules = Object.keys(nativeModules)
     .map(name => {
       const {properties} = nativeModules[name];
-      const traversedProperties = properties
-        .map(prop => {
-          const traversedArgs = prop.typeAnnotation.params
-            .map(param => {
-              const translatedParam = translatePrimitiveJSTypeToCpp(
-                param.typeAnnotation,
-                `Unspopported type for param "${param.name}" in ${
-                  prop.name
-                }. Found: ${param.typeAnnotation.type}`,
-              );
-              const isObject = translatedParam.startsWith('jsi::');
-              return (
-                (isObject
-                  ? 'const ' + translatedParam + ' &'
-                  : translatedParam + ' ') + param.name
-              );
-            })
-            .join(', ');
-          return propertyTemplate
-            .replace('::_PROPERTY_NAME_::', prop.name)
-            .replace(
-              '::_RETURN_VALUE_::',
-              translatePrimitiveJSTypeToCpp(
-                prop.typeAnnotation.returnTypeAnnotation,
-                `Unspopported return type for ${prop.name}. Found: ${
-                  prop.typeAnnotation.returnTypeAnnotation.type
-                }`,
-              ),
-            )
-            .replace(
-              '::_ARGS_::',
-              traversedArgs === '' ? '' : ', ' + traversedArgs,
-            );
-        })
-        .join('\n');
+      const traversedProperties = renderProperties(properties, false);
+      const traversedExampleProperties = renderProperties(properties, true);
+
+
       return moduleTemplate
+        .replace(/::_EXAMPLE_MODULE_PROPERTIES_::/g, traversedExampleProperties)
         .replace(/::_MODULE_PROPERTIES_::/g, traversedProperties)
-        .replace(/::_MODULE_NAME_::/g, name)
-        .replace('::_PROPERTIES_MAP_::', '');
+        .replace(/::_MODULE_IMPL_NAME_::/g, `T${name}Impl`)
+        .replace(/::_MODULE_NAME_::/g, name);
     })
     .join('\n');
 
-  const fileName = 'NativeModules.h';
-  const replacedTemplate = template.replace(/::_MODULES_::/g, modules);
+  const fileName = 'NativeModules.g.h';
+  const replacedTemplate = template.replace(/::_NAMESPACE_::/g, namespace).replace(/::_MODULES_::/g, modules);
 
   return new Map([[fileName, replacedTemplate]]);
+};
 }

From 6fefd943694c987834097168649a77834891ad32 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Tue, 31 Mar 2020 09:17:04 -0700
Subject: [PATCH 3/9] formatting

---
 .../windows/SampleLibraryCPP/ReactPackageProvider.cpp           | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
index 0803c5502fa..738efaf934b 100644
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
@@ -25,7 +25,7 @@ namespace SampleLibraryCpp {
 void RegisterModule(ReactModuleBuilder<::SampleLibraryCpp::MyModule> &moduleBuilder) {
   RegisterMyModuleModule(moduleBuilder);
 }
-}
+} // namespace SampleLibraryCpp
 
 namespace winrt::SampleLibraryCpp::implementation {
 

From fac99a024f387e71698bc18cc89c0365b86eb408 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Tue, 31 Mar 2020 09:17:29 -0700
Subject: [PATCH 4/9] formatting

---
 .../windows/SampleLibraryCPP/MyModule.h       | 49 +++++++++----------
 1 file changed, 24 insertions(+), 25 deletions(-)

diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
index f4ecad285aa..ac16929b89b 100644
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
@@ -10,31 +10,30 @@
 namespace SampleLibraryCpp {
 
 struct MyModule {
-    void Initialize(IReactContext const & /*reactContext*/) noexcept {
-    }
-
-    const bool const1 = false;
-    const double const2 = 1.234;
-    const std::string const3 = "abc";
-
-    void voidFunc() noexcept {
-      DEBUG_MYMODULE_OUTPUT("voidFunc");
-    }
-
-    bool getBool(bool arg) noexcept {
-      DEBUG_MYMODULE_OUTPUT("getBool", arg);
-      return arg;
-    }
-
-    double getNumber(double arg) noexcept {
-      DEBUG_MYMODULE_OUTPUT("getNumber", arg);
-      return arg;
-    }
-
-    std::string getString(std::string arg) noexcept {
-      DEBUG_MYMODULE_OUTPUT("getString", arg);
-      return arg;
-    }
+  void Initialize(IReactContext const & /*reactContext*/) noexcept {}
+
+  const bool const1 = false;
+  const double const2 = 1.234;
+  const std::string const3 = "abc";
+
+  void voidFunc() noexcept {
+    DEBUG_MYMODULE_OUTPUT("voidFunc");
+  }
+
+  bool getBool(bool arg) noexcept {
+    DEBUG_MYMODULE_OUTPUT("getBool", arg);
+    return arg;
+  }
+
+  double getNumber(double arg) noexcept {
+    DEBUG_MYMODULE_OUTPUT("getNumber", arg);
+    return arg;
+  }
+
+  std::string getString(std::string arg) noexcept {
+    DEBUG_MYMODULE_OUTPUT("getString", arg);
+    return arg;
+  }
 };
 
 } // namespace SampleLibraryCpp

From ea1549663c8c96d67b9370da4b1b9f6cbfba1496 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Wed, 22 Apr 2020 13:27:56 -0700
Subject: [PATCH 5/9] Get basic codegen sample working.

---
 .../NativeMyModule.js                         |  12 +-
 .../codegen/NativeModules.g.h                 | 114 +++---
 .../just-task.js                              |  10 +-
 .../windows/SampleLibraryCPP/MyModule.h       |  44 ++-
 .../SampleLibraryCPP/ReactPackageProvider.cpp |  12 +-
 .../react-native-windows-codegen/package.json |   9 +-
 .../src/generators/GenerateNM2.ts             | 353 ++++++++++++------
 yarn.lock                                     |  53 +++
 8 files changed, 410 insertions(+), 197 deletions(-)

diff --git a/packages/microsoft-reactnative-sampleapps/NativeMyModule.js b/packages/microsoft-reactnative-sampleapps/NativeMyModule.js
index 1663d29a2eb..bb647a3e3d1 100644
--- a/packages/microsoft-reactnative-sampleapps/NativeMyModule.js
+++ b/packages/microsoft-reactnative-sampleapps/NativeMyModule.js
@@ -13,22 +13,20 @@ import * as TurboModuleRegistry from 'react-native/Libraries/TurboModule/TurboMo
 
 export interface Spec extends TurboModule {
   // Exported methods.
-  /*
   +getConstants: () => {|
     const1: boolean,
     const2: number,
     const3: string,
   |};
-  */
   +voidFunc: () => void;
   +getBool: (arg: boolean) => boolean;
   +getNumber: (arg: number) => number;
   +getString: (arg: string) => string;
-  // +getArray: (arg: Array<any>) => Array<any>;
-  // +getObject: (arg: Object) => Object;
-  // +getValue: (x: number, y: string, z: Object) => Object;
-  // +getValueWithCallback: (callback: (value: string) => void) => void;
-  // +getValueWithPromise: (error: boolean) => Promise<string>;
+  +getArray: (arg: Array<any>) => Array<any>;
+  +getObject: (arg: Object) => Object;
+  +getValue: (x: number, y: string, z: Object) => Object;
+  +getValueWithCallback: (callback: (value: string) => void) => void;
+  +getValueWithPromise: (error: boolean) => Promise<string>;
 }
 
 export default (TurboModuleRegistry.getEnforcing<Spec>('MyModule'): Spec);
diff --git a/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h b/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
index 82325392c59..5a6559c3cf3 100644
--- a/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
+++ b/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
@@ -1,66 +1,82 @@
 
 /**
- * This file is auto-generated from a TurboModule Spec file
+ * This file is auto-generated.
  */
 
 #pragma once
 
 #include "NativeModules.h"
+#include <tuple>
 
 namespace SampleLibraryCpp {
 
 /*
  * This function registers a class as implementing a TurboModule Spec
  * The class must implement all the methods as required by the Spec.
- * Methods may be implemented using one of the method signatures provided above the RegisterMethod calls
- *
- * Note that methods can be optionally written using a veriety of method signatures which may be preferable
- * depending on your scenario.
- * 
- * An example implementation you could copy/paste is provided here:
-
-class MyModule {
-  void Initialize() {
-  }
-
-  void MyModule::voidFunc() noexcept {
-    throw std::logic_error("MyModule::voidFunc not yet implemented.");
-  }
-
-  bool MyModule::getBool(bool) noexcept {
-    throw std::logic_error("MyModule::getBool not yet implemented.");
-  }
-
-  double MyModule::getNumber(double) noexcept {
-    throw std::logic_error("MyModule::getNumber not yet implemented.");
-  }
-
-  std::string MyModule::getString(std::string) noexcept {
-    throw std::logic_error("MyModule::getString not yet implemented.");
+ */
+struct MyModuleSpec : winrt::Microsoft::ReactNative::TurboModuleSpec {
+  static constexpr auto methods = std::tuple{
+      Method<void() noexcept>{0, L"voidFunc"},
+      SyncMethod<bool(bool) noexcept>{1, L"getBool"},
+      SyncMethod<double(double) noexcept>{2, L"getNumber"},
+      SyncMethod<std::string(std::string) noexcept>{3, L"getString"},
+      SyncMethod<JSValueArray(JSValueArray) noexcept>{4, L"getArray"},
+      SyncMethod<JSValueObject(JSValueObject) noexcept>{5, L"getObject"},
+      SyncMethod<JSValueObject(double,std::string,JSValueObject) noexcept>{6, L"getValue"},
+      Method<void(Callback<JSValue>) noexcept>{7, L"getValueWithCallback"},
+      Method<void(bool,Promise<JSValue>) noexcept>{8, L"getValueWithPromise"},
+  };
+
+  template <class TModule>
+  static constexpr void ValidateModule() noexcept {
+    constexpr auto methodCheckResults = CheckMethods<TModule, MyModuleSpec>();
+
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          0,
+          "voidFunc",
+          "    REACT_METHOD(voidFunc) void voidFunc() noexcept { /* implementation */ }}",
+          "    REACT_METHOD(voidFunc) static void voidFunc() noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          1,
+          "getBool",
+          "    REACT_SYNC_METHOD(getBool) bool getBool(bool arg) noexcept { /* implementation */ }}",
+          "    REACT_SYNC_METHOD(getBool) static bool getBool(bool arg) noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          2,
+          "getNumber",
+          "    REACT_SYNC_METHOD(getNumber) double getNumber(double arg) noexcept { /* implementation */ }}",
+          "    REACT_SYNC_METHOD(getNumber) static double getNumber(double arg) noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          3,
+          "getString",
+          "    REACT_SYNC_METHOD(getString) std::string getString(std::string arg) noexcept { /* implementation */ }}",
+          "    REACT_SYNC_METHOD(getString) static std::string getString(std::string arg) noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          4,
+          "getArray",
+          "    REACT_SYNC_METHOD(getArray) React::JSValueArray getArray(React::JSValueArray && arg) noexcept { /* implementation */ }}",
+          "    REACT_SYNC_METHOD(getArray) static React::JSValueArray getArray(React::JSValueArray && arg) noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          5,
+          "getObject",
+          "    REACT_SYNC_METHOD(getObject) React::JSValueObject getObject(React::JSValueObject && arg) noexcept { /* implementation */ }}",
+          "    REACT_SYNC_METHOD(getObject) static React::JSValueObject getObject(React::JSValueObject && arg) noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          6,
+          "getValue",
+          "    REACT_SYNC_METHOD(getValue) React::JSValueObject getValue(double x, std::string y, React::JSValueObject && z) noexcept { /* implementation */ }}",
+          "    REACT_SYNC_METHOD(getValue) static React::JSValueObject getValue(double x, std::string y, React::JSValueObject && z) noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          7,
+          "getValueWithCallback",
+          "    REACT_METHOD(getValueWithCallback) void getValueWithCallback(std::function<void(React::JSValue const &)> const & callback) noexcept { /* implementation */ }}",
+          "    REACT_METHOD(getValueWithCallback) static void getValueWithCallback(std::function<void(React::JSValue const &)> const & callback) noexcept { /* implementation */ }}");
+    REACT_SHOW_METHOD_SPEC_ERRORS(
+          8,
+          "getValueWithPromise",
+          "    REACT_METHOD(getValueWithPromise) void getValueWithPromise(bool error, React::ReactPromise<React::JSValue> &&result) noexcept { /* implementation */ }}",
+          "    REACT_METHOD(getValueWithPromise) static void getValueWithPromise(bool error, React::ReactPromise<React::JSValue> &&result) noexcept { /* implementation */ }}");
   }
 };
 
- */
-template <typename TMyModuleImpl>
-void RegisterMyModuleModule(ReactModuleBuilder<TMyModuleImpl> &moduleBuilder) noexcept {
-  moduleBuilder.RegisterModuleName(L"MyModule");
-  moduleBuilder.RegisterInitMethod(&TMyModuleImpl::Initialize);
-
-  // This method can be implemented using the following method signature:
-  // void TMyModuleImpl::voidFunc() noexcept;
-  moduleBuilder.RegisterMethod/*<void()>*/(&TMyModuleImpl::voidFunc, L"voidFunc");
-
-  // This method can be implemented using the following method signature:
-  // bool TMyModuleImpl::getBool(bool) noexcept;
-  moduleBuilder.RegisterSyncMethod/*<bool(bool)>*/(&TMyModuleImpl::getBool, L"getBool");
-
-  // This method can be implemented using the following method signature:
-  // double TMyModuleImpl::getNumber(double) noexcept;
-  moduleBuilder.RegisterSyncMethod/*<double(double)>*/(&TMyModuleImpl::getNumber, L"getNumber");
-
-  // This method can be implemented using the following method signature:
-  // std::string TMyModuleImpl::getString(std::string) noexcept;
-  moduleBuilder.RegisterSyncMethod/*<std::string(std::string)>*/(&TMyModuleImpl::getString, L"getString");
-}
-
 } // namespace SampleLibraryCpp
diff --git a/packages/microsoft-reactnative-sampleapps/just-task.js b/packages/microsoft-reactnative-sampleapps/just-task.js
index df5a61a38b7..9339105da9c 100644
--- a/packages/microsoft-reactnative-sampleapps/just-task.js
+++ b/packages/microsoft-reactnative-sampleapps/just-task.js
@@ -8,6 +8,7 @@
 const {
   task,
   series,
+  parallel,
   option,
   argv,
   tscTask,
@@ -15,6 +16,7 @@ const {
 } = require('just-scripts');
 const fs = require('fs');
 const path = require('path');
+const {execSync} = require('child_process');
 
 option('production');
 option('clean');
@@ -36,6 +38,12 @@ task('ts', () => {
   });
 });
 
+task('codegen', () => {
+  execSync(
+    'npx react-native-windows-codegen --file NativeMyModule.js --namespace SampleLibraryCpp',
+  );
+});
+
 function ensureDirectoryExists(filePath) {
   const dir = path.dirname(filePath);
   if (!fs.existsSync(dir)) {
@@ -49,6 +57,6 @@ task('prepareBundle', () => {
   ensureDirectoryExists('windows/SampleAppCPP/Bundle');
 });
 
-task('build', series('ts'));
+task('build', parallel('ts', 'codegen'));
 task('lint', series('eslint'));
 task('lint:fix', series('eslint:fix'));
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
index ac16929b89b..c9d9415ac12 100644
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/MyModule.h
@@ -9,31 +9,67 @@
 
 namespace SampleLibraryCpp {
 
+REACT_MODULE(MyModule)
 struct MyModule {
-  void Initialize(IReactContext const & /*reactContext*/) noexcept {}
-
-  const bool const1 = false;
+  // The spec file does not currently validate constants
+  REACT_CONSTANT(const1)
+  const bool const1 = true;
+  REACT_CONSTANT(const2)
   const double const2 = 1.234;
-  const std::string const3 = "abc";
+  REACT_CONSTANT(const3)
+  const std::string const3{"const3"};
 
+  REACT_METHOD(voidFunc)
   void voidFunc() noexcept {
     DEBUG_MYMODULE_OUTPUT("voidFunc");
   }
 
+  REACT_SYNC_METHOD(getBool)
   bool getBool(bool arg) noexcept {
     DEBUG_MYMODULE_OUTPUT("getBool", arg);
     return arg;
   }
 
+  REACT_SYNC_METHOD(getNumber)
   double getNumber(double arg) noexcept {
     DEBUG_MYMODULE_OUTPUT("getNumber", arg);
     return arg;
   }
 
+  REACT_SYNC_METHOD(getString)
   std::string getString(std::string arg) noexcept {
     DEBUG_MYMODULE_OUTPUT("getString", arg);
     return arg;
   }
+
+  REACT_SYNC_METHOD(getArray)
+  React::JSValueArray getArray(React::JSValueArray && /*arg*/) noexcept {
+    return React::JSValueArray{"X", 4, true};
+  }
+
+  REACT_SYNC_METHOD(getObject)
+  React::JSValueObject getObject(React::JSValueObject && /*arg*/) noexcept {
+    return React::JSValueObject{{"X", 4}, {"Y", 2}};
+  }
+
+  REACT_SYNC_METHOD(getValue)
+  React::JSValueObject getValue(double x, std::string y, JSValueObject &&z) noexcept {
+    return React::JSValueObject{{"X", x}, {"Y", y}, {"Z", std::move(z)}};
+  }
+
+  REACT_METHOD(getValueWithCallback)
+  void getValueWithCallback(std::function<void(React::JSValue const &)> const &callback) noexcept {
+    callback(React::JSValue{"some string"});
+  }
+
+  REACT_METHOD(getValueWithPromise)
+  void getValueWithPromise(bool error, React::ReactPromise<React::JSValue> &&result) noexcept {
+    if (error) {
+      result.Reject("Failure");
+    } else {
+      result.Resolve(React::JSValue{"Succeeded"});
+    }
+  }
 };
 
 } // namespace SampleLibraryCpp
diff --git a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
index 738efaf934b..c7dd9c8c335 100644
--- a/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
+++ b/packages/microsoft-reactnative-sampleapps/windows/SampleLibraryCPP/ReactPackageProvider.cpp
@@ -19,19 +19,13 @@
 
 using namespace winrt::Microsoft::ReactNative;
 
-namespace SampleLibraryCpp {
-
-// Lame that we need this right now
-void RegisterModule(ReactModuleBuilder<::SampleLibraryCpp::MyModule> &moduleBuilder) {
-  RegisterMyModuleModule(moduleBuilder);
-}
-} // namespace SampleLibraryCpp
-
 namespace winrt::SampleLibraryCpp::implementation {
 
 void ReactPackageProvider::CreatePackage(IReactPackageBuilder const &packageBuilder) noexcept {
   AddAttributedModules(packageBuilder);
-  packageBuilder.AddModule(L"MyModule", MakeModuleProvider<::SampleLibraryCpp::MyModule>());
+
+  packageBuilder.AddModule(
+      L"MyModule", MakeTurboModuleProvider<::SampleLibraryCpp::MyModule, ::SampleLibraryCpp::MyModuleSpec>());
   packageBuilder.AddViewManager(
       L"CustomUserControlViewManagerCpp", []() { return winrt::make<CustomUserControlViewManagerCpp>(); });
   packageBuilder.AddViewManager(L"CircleViewManagerCpp", []() { return winrt::make<CircleViewManagerCpp>(); });
diff --git a/packages/react-native-windows-codegen/package.json b/packages/react-native-windows-codegen/package.json
index 680e0aaaf05..43dc41c6959 100644
--- a/packages/react-native-windows-codegen/package.json
+++ b/packages/react-native-windows-codegen/package.json
@@ -18,17 +18,12 @@
   "dependencies": {
     "chalk": "^3",
     "react-native-tscodegen": "0.0.10",
+    "react-native-codegen": "0.0.2",
     "yargs": "^15.1.0"
   },
   "devDependencies": {
     "@types/chalk": "^2.2.0",
     "@types/yargs": "^15.0.3",
     "just-scripts": "^0.36.1"
-  },
-  "files": [
-    "bin.js",
-    "lib-commonjs",
-    "README.md",
-    "react-native-codegen/src"
-  ]
+  }
 }
diff --git a/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
index d78edb6a370..4e63e324b5f 100644
--- a/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
+++ b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
@@ -1,6 +1,7 @@
 /**
  * Copyright (c) Microsoft Corporation.
  * Licensed under the MIT License.
+ * @format
  */
 
 'use strict';
@@ -8,7 +9,8 @@
 import {
   SchemaType,
   MethodTypeShape,
-  //FunctionTypeAnnotationParam,
+  // FunctionTypeAnnotation,
+  FunctionTypeAnnotationParam,
   FunctionTypeAnnotationParamTypeAnnotation,
   FunctionTypeAnnotationReturn,
 } from 'react-native-tscodegen';
@@ -19,45 +21,29 @@ const moduleTemplate = `
 /*
  * This function registers a class as implementing a TurboModule Spec
  * The class must implement all the methods as required by the Spec.
- * Methods may be implemented using one of the method signatures provided above the RegisterMethod calls
- *
- * Note that methods can be optionally written using a veriety of method signatures which may be preferable
- * depending on your scenario.
- * 
- * An example implementation you could copy/paste is provided here:
-
-class ::_MODULE_NAME_:: {
-  void Initialize() {
-  }
-::_EXAMPLE_MODULE_PROPERTIES_::
-};
-
  */
-template <typename TMyModuleImpl>
-void Register::_MODULE_NAME_::Module(ReactModuleBuilder<::_MODULE_IMPL_NAME_::> &moduleBuilder) noexcept {
-  moduleBuilder.RegisterModuleName(L"::_MODULE_NAME_::");
-  moduleBuilder.RegisterInitMethod(&::_MODULE_IMPL_NAME_::::Initialize);
-::_MODULE_PROPERTIES_::
-}`;
-
-const moduleMethodTemplate = `
-  // This method can be implemented using the following method signature:
-  // ::_METHOD_RETURN_TYPE_:: ::_MODULE_IMPL_NAME_::::::_METHOD_NAME_::(::_METHOD_ARGS_::) noexcept;
-  moduleBuilder.Register::_METHOD_SYNC_::Method/*<::_METHOD_TYPE_::>*/(&::_MODULE_IMPL_NAME_::::::_METHOD_NAME_::, L"::_METHOD_NAME_::");`;
-
-const exampleMethodTemplate = `
-  ::_METHOD_RETURN_TYPE_:: ::_MODULE_NAME_::::::_METHOD_NAME_::(::_METHOD_ARGS_::) noexcept {
-    throw std::logic_error("::_MODULE_NAME_::::::_METHOD_NAME_:: not yet implemented.");
-  }`;
+struct ::_MODULE_NAME_::Spec : winrt::Microsoft::ReactNative::TurboModuleSpec {
+  static constexpr auto methods = std::tuple{
+::_MODULE_PROPERTIES_TUPLE_::
+  };
+
+  template <class TModule>
+  static constexpr void ValidateModule() noexcept {
+    constexpr auto methodCheckResults = CheckMethods<TModule, ::_MODULE_NAME_::Spec>();
+
+::_MODULE_PROPERTIES_SPEC_ERRORS_::
+  }
+};`;
 
 const template = `
 /**
- * This file is auto-generated from a TurboModule Spec file
+ * This file is auto-generated.
  */
 
 #pragma once
 
 #include "NativeModules.h"
+#include <tuple>
 
 namespace ::_NAMESPACE_:: {
 ::_MODULES_::
@@ -65,9 +51,66 @@ namespace ::_NAMESPACE_:: {
 } // namespace ::_NAMESPACE_::
 `;
 
-function translatePrimitiveJSTypeToCpp(
-  type:    FunctionTypeAnnotationParamTypeAnnotation    | FunctionTypeAnnotationReturn,
-  error: string,
+function translateSpecFunctionParam(
+  param: FunctionTypeAnnotationParam,
+): string {
+  switch (param.typeAnnotation.type) {
+    case 'StringTypeAnnotation':
+      return 'std::string';
+    case 'NumberTypeAnnotation':
+    case 'FloatTypeAnnotation':
+      return 'double';
+    case 'Int32TypeAnnotation':
+      return 'int';
+    case 'BooleanTypeAnnotation':
+      return 'bool';
+    case 'FunctionTypeAnnotation': {
+      // Ideally we'd get more information about the expected parameters of the callback
+      // But the current schema doesn't seem to provide the necessary information.
+      return 'Callback<JSValue>';
+    }
+    case 'ArrayTypeAnnotation':
+      // Ideally we'd get more information about the expected type of the array
+      // But the current schema doesn't seem to provide the necessary information.
+      return 'JSValueArray';
+    case 'GenericObjectTypeAnnotation':
+      return 'JSValueObject';
+    default:
+      throw new Error(`Unhandled type: ${param.typeAnnotation.type}`);
+  }
+}
+
+function translateFunctionParam(param: FunctionTypeAnnotationParam): string {
+  switch (param.typeAnnotation.type) {
+    case 'StringTypeAnnotation':
+      return 'std::string';
+    case 'NumberTypeAnnotation':
+    case 'FloatTypeAnnotation':
+      return 'double';
+    case 'Int32TypeAnnotation':
+      return 'int';
+    case 'BooleanTypeAnnotation':
+      return 'bool';
+    case 'FunctionTypeAnnotation': {
+      // Ideally we'd get more information about the expected parameters of the callback
+      // But the current schema doesn't seem to provide the necessary information.
+      return 'std::function<void(React::JSValue const &)> const &';
+    }
+    case 'ArrayTypeAnnotation':
+      // Ideally we'd get more information about the expected type of the array
+      // But the current schema doesn't seem to provide the necessary information.
+      return 'React::JSValueArray &&';
+    case 'GenericObjectTypeAnnotation':
+      return 'React::JSValueObject &&';
+    default:
+      throw new Error(`Unhandled type: ${param.typeAnnotation.type}`);
+  }
+}
+
+function translateSpecReturnType(
+  type:
+    | FunctionTypeAnnotationParamTypeAnnotation
+    | FunctionTypeAnnotationReturn,
 ) {
   switch (type.type) {
     case 'VoidTypeAnnotation':
@@ -81,111 +124,181 @@ function translatePrimitiveJSTypeToCpp(
       return 'int';
     case 'BooleanTypeAnnotation':
       return 'bool';
-    case 'GenericObjectTypeAnnotation':
-    case 'ObjectTypeAnnotation':
-      return 'jsi::Object';
-/*
+    case 'GenericPromiseTypeAnnotation':
+      return 'void';
     case 'ArrayTypeAnnotation':
-      return 'jsi::Array';
-    case 'FunctionTypeAnnotation':
-      return 'jsi::Function';
+      // Ideally we'd get more information about the expected type of the array
+      // But the current schema doesn't seem to provide the necessary information.
+      return 'JSValueArray';
+    case 'GenericObjectTypeAnnotation':
+      return 'JSValueObject';
+    default:
+      throw new Error(`Unhandled type: ${type.type}`);
+  }
+}
+
+function translateImplReturnType(
+  type:
+    | FunctionTypeAnnotationParamTypeAnnotation
+    | FunctionTypeAnnotationReturn,
+) {
+  switch (type.type) {
+    case 'VoidTypeAnnotation':
+      return 'void';
+    case 'StringTypeAnnotation':
+      return 'std::string';
+    case 'NumberTypeAnnotation':
+    case 'FloatTypeAnnotation':
+      return 'double';
+    case 'Int32TypeAnnotation':
+      return 'int';
+    case 'BooleanTypeAnnotation':
+      return 'bool';
     case 'GenericPromiseTypeAnnotation':
-      return 'jsi::Value';
-*/
+      return 'void';
+    case 'ArrayTypeAnnotation':
+      // Ideally we'd get more information about the expected type of the array
+      // But the current schema doesn't seem to provide the necessary information.
+      return 'React::JSValueArray';
+    case 'GenericObjectTypeAnnotation':
+      return 'React::JSValueObject';
     default:
-      throw new Error(error);
+      throw new Error(`Unhandled type: ${type.type}`);
   }
 }
 
-function renderProperties(properties : ReadonlyArray<MethodTypeShape>, example : boolean) : string {
-  return properties
-  .map(prop => {
+function translateSpecArgs(params: ReadonlyArray<FunctionTypeAnnotationParam>) {
+  return params.map(param => {
+    const translatedParam = translateSpecFunctionParam(param);
+    return `${translatedParam}`;
+  });
+}
+
+function translateArgs(params: ReadonlyArray<FunctionTypeAnnotationParam>) {
+  return params.map(param => {
+    const translatedParam = translateFunctionParam(param);
+    return `${translatedParam} ${param.name}`;
+  });
+}
 
-    const isMethodSync = prop.typeAnnotation.returnTypeAnnotation.type !== 'VoidTypeAnnotation';
+function isMethodSync(prop: MethodTypeShape) {
+  return (
+    prop.typeAnnotation.returnTypeAnnotation.type !== 'VoidTypeAnnotation' &&
+    prop.typeAnnotation.returnTypeAnnotation.type !==
+      'GenericPromiseTypeAnnotation'
+  );
+}
 
-    let params = prop.typeAnnotation.params;
+function isPromise(prop: MethodTypeShape) {
+  return (
+    prop.typeAnnotation.returnTypeAnnotation.type ===
+    'GenericPromiseTypeAnnotation'
+  );
+}
 
-    /*
-    let hasCallback = false;
-    // If last arg is a callback
-    if (prop.typeAnnotation.returnTypeAnnotation.type === 'VoidTypeAnnotation' &&
-      params.length && params[params.length - 1].typeAnnotation.type === 'FunctionTypeAnnotation') {
-      hasCallback = true;
-    }
-    */
-
-    const traversedArgs = params
-      .map(param => {
-        const translatedParam = translatePrimitiveJSTypeToCpp(
-          param.typeAnnotation,
-          `Unspopported type for param "${param.name}" in ${
-            prop.name
-          }. Found: ${param.typeAnnotation.type}`,
-        );
-        return `${translatedParam}`;
-        /*
-        const isObject = translatedParam.startsWith('jsi::');
-        return (
-          (isObject
-            ? 'const ' + translatedParam + ' &'
-            : translatedParam + ' ') + param.name
-        );
-        */
-      })
-      .join(', ');
-
-    const translatedReturnParam = translatePrimitiveJSTypeToCpp(
-      prop.typeAnnotation.returnTypeAnnotation,
-      `Unsupported return type for ${prop.name}. Found: ${
-        prop.typeAnnotation.returnTypeAnnotation.type
-      }`);
-
-    return (example ? exampleMethodTemplate : moduleMethodTemplate)
-      .replace('::_METHOD_SYNC_::', isMethodSync ? 'Sync' : '')
-      .replace(/::_METHOD_NAME_::/g, prop.name)
-      .replace('::_METHOD_RETURN_TYPE_::', translatedReturnParam)
-      .replace('::_METHOD_ARGS_::', traversedArgs)
-      .replace('::_METHOD_TYPE_::', `${translatedReturnParam}(${traversedArgs})`);
-  })
-  .join('\n');
+function getPossibleMethodSignatures(prop: MethodTypeShape): string[] {
+  let args = translateArgs(prop.typeAnnotation.params);
+  if (isPromise(prop)) {
+    // Sadly, currently, the schema doesn't currently provide us information on the type of the promise.
+    args.push('React::ReactPromise<React::JSValue> &&result');
+  }
+
+  // TODO be much more exhastive on the possible method signatures that can be used..
+  let sig = `REACT_${isMethodSync(prop) ? 'SYNC_' : ''}METHOD(${
+    prop.name
+  }) ${translateImplReturnType(prop.typeAnnotation.returnTypeAnnotation)} ${
+    prop.name
+  }(${args.join(', ')}) noexcept { /* implementation */ }}`;
+  let staticsig = `REACT_${isMethodSync(prop) ? 'SYNC_' : ''}METHOD(${
+    prop.name
+  }) static ${translateImplReturnType(
+    prop.typeAnnotation.returnTypeAnnotation,
+  )} ${prop.name}(${args.join(', ')}) noexcept { /* implementation */ }}`;
+
+  return [sig, staticsig];
 }
 
-export function createNM2Generator({namespace} : {namespace: string}) {
-  return (  _libraryName: string,
-    schema: SchemaType,
-    _moduleSpecName: string) : FilesOutput => {
+function translatePossibleMethodSignatures(prop: MethodTypeShape): string {
+  return getPossibleMethodSignatures(prop)
+    .map(sig => `"    ${sig}"`)
+    .join(',\n          ');
+}
+
+function renderProperties(
+  properties: ReadonlyArray<MethodTypeShape>,
+  tuple: boolean,
+): string {
+  // We skip the constants for now, since we dont have Spec file validation of them.
+  return properties
+    .filter(prop => prop.name !== 'getConstants')
+    .map((prop, index) => {
+      let params = prop.typeAnnotation.params;
 
-  const nativeModules = Object.keys(schema.modules)
-    .map(moduleName => {
-      const modules = schema.modules[moduleName].nativeModules;
-      if (modules == null) {
-        return null;
+      const traversedArgs = translateSpecArgs(params);
+
+      const translatedReturnParam = translateSpecReturnType(
+        prop.typeAnnotation.returnTypeAnnotation,
+      );
+
+      if (isPromise(prop)) {
+        // Sadly, currently, the schema doesn't currently provide us information on the type of the promise.
+        traversedArgs.push('Promise<JSValue>');
       }
 
-      return modules;
+      if (tuple) {
+        return `      ${
+          isMethodSync(prop) ? 'Sync' : ''
+        }Method<${translatedReturnParam}(${traversedArgs.join(
+          ',',
+        )}) noexcept>{${index}, L"${prop.name}"},`;
+      } else {
+        return `    REACT_SHOW_METHOD_SPEC_ERRORS(
+          ${index},
+          "${prop.name}",
+          ${translatePossibleMethodSignatures(prop)});`;
+      }
     })
-    .filter(Boolean)
-    .reduce((acc, components) => Object.assign(acc, components), {});
+    .join('\n');
+}
 
+export function createNM2Generator({namespace}: {namespace: string}) {
+  return (
+    _libraryName: string,
+    schema: SchemaType,
+    _moduleSpecName: string,
+  ): FilesOutput => {
+    // console.log(JSON.stringify(schema, null, 2));
 
-  const modules = Object.keys(nativeModules)
-    .map(name => {
-      const {properties} = nativeModules[name];
-      const traversedProperties = renderProperties(properties, false);
-      const traversedExampleProperties = renderProperties(properties, true);
+    const nativeModules = Object.keys(schema.modules)
+      .map(moduleName => {
+        const modules = schema.modules[moduleName].nativeModules;
+        if (modules == null) {
+          return null;
+        }
 
+        return modules;
+      })
+      .filter(Boolean)
+      .reduce((acc, components) => Object.assign(acc, components), {});
 
-      return moduleTemplate
-        .replace(/::_EXAMPLE_MODULE_PROPERTIES_::/g, traversedExampleProperties)
-        .replace(/::_MODULE_PROPERTIES_::/g, traversedProperties)
-        .replace(/::_MODULE_IMPL_NAME_::/g, `T${name}Impl`)
-        .replace(/::_MODULE_NAME_::/g, name);
-    })
-    .join('\n');
+    const modules = Object.keys(nativeModules)
+      .map(name => {
+        const {properties} = nativeModules[name];
+        const traversedProperties = renderProperties(properties, false);
+        const traversedPropertyTuples = renderProperties(properties, true);
+
+        return moduleTemplate
+          .replace(/::_MODULE_PROPERTIES_TUPLE_::/g, traversedPropertyTuples)
+          .replace(/::_MODULE_PROPERTIES_SPEC_ERRORS_::/g, traversedProperties)
+          .replace(/::_MODULE_NAME_::/g, name);
+      })
+      .join('\n');
 
-  const fileName = 'NativeModules.g.h';
-  const replacedTemplate = template.replace(/::_NAMESPACE_::/g, namespace).replace(/::_MODULES_::/g, modules);
+    const fileName = 'NativeModules.g.h';
+    const replacedTemplate = template
+      .replace(/::_NAMESPACE_::/g, namespace)
+      .replace(/::_MODULES_::/g, modules);
 
-  return new Map([[fileName, replacedTemplate]]);
-};
+    return new Map([[fileName, replacedTemplate]]);
+  };
 }
diff --git a/yarn.lock b/yarn.lock
index e024d4f06fb..fe1b4f80952 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4143,6 +4143,11 @@ ast-types@0.11.7:
   resolved "https://registry.yarnpkg.com/ast-types/-/ast-types-0.11.7.tgz#f318bf44e339db6a320be0009ded64ec1471f46c"
   integrity sha512-2mP3TwtkY/aTv5X3ZsMpNAbOnyoC/aMJwJSoaELPkHId0nSQgFcnU4dRW3isxiz7+zBexk0ym3WNVjMiQBnJSw==
 
+ast-types@0.13.3:
+  version "0.13.3"
+  resolved "https://registry.yarnpkg.com/ast-types/-/ast-types-0.13.3.tgz#50da3f28d17bdbc7969a3a2d83a0e4a72ae755a7"
+  integrity sha512-XTZ7xGML849LkQP86sWdQzfhwbt3YwIO6MqbX9mUNYY98VKaaVZP7YNNm70IpwecbkkxmfC5IYAzOQ/2p29zRA==
+
 astral-regex@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/astral-regex/-/astral-regex-1.0.0.tgz#6c8c3fb827dd43ee3918f27b82782ab7658a6fd9"
@@ -6853,6 +6858,11 @@ flow-parser@0.*:
   resolved "https://registry.yarnpkg.com/flow-parser/-/flow-parser-0.113.0.tgz#5b5913c54833918d0c3136ba69f6cf0cdd85fc20"
   integrity sha512-+hRyEB1sVLNMTMniDdM1JIS8BJ3HUL7IFIJaxX+t/JUy0GNYdI0Tg1QLx8DJmOF8HeoCrUDcREpnDAc/pPta3w==
 
+flow-parser@^0.121.0:
+  version "0.121.0"
+  resolved "https://registry.yarnpkg.com/flow-parser/-/flow-parser-0.121.0.tgz#9f9898eaec91a9f7c323e9e992d81ab5c58e618f"
+  integrity sha512-1gIBiWJNR0tKUNv8gZuk7l9rVX06OuLzY9AoGio7y/JT4V1IZErEMEq2TJS+PFcw/y0RshZ1J/27VfK1UQzYVg==
+
 flush-write-stream@^1.0.0:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/flush-write-stream/-/flush-write-stream-1.1.1.tgz#8dd7d873a1babc207d94ead0c2e0e44276ebf2e8"
@@ -8566,6 +8576,30 @@ jscodeshift@0.6.4, jscodeshift@^0.6.2:
     temp "^0.8.1"
     write-file-atomic "^2.3.0"
 
+jscodeshift@^0.7.0:
+  version "0.7.0"
+  resolved "https://registry.yarnpkg.com/jscodeshift/-/jscodeshift-0.7.0.tgz#4eee7506fd4fdacbd80340287d61575af991fdab"
+  integrity sha512-Kt6rpTa1HVhAWagD6J0y6qxxqRmDgkFvczerLgOsDNSGoUZSmq2CO1vFRcda9OV1BaZKSHCIh+VREPts5tB/Ig==
+  dependencies:
+    "@babel/core" "^7.1.6"
+    "@babel/parser" "^7.1.6"
+    "@babel/plugin-proposal-class-properties" "^7.1.0"
+    "@babel/plugin-proposal-object-rest-spread" "^7.0.0"
+    "@babel/preset-env" "^7.1.6"
+    "@babel/preset-flow" "^7.0.0"
+    "@babel/preset-typescript" "^7.1.0"
+    "@babel/register" "^7.0.0"
+    babel-core "^7.0.0-bridge.0"
+    colors "^1.1.2"
+    flow-parser "0.*"
+    graceful-fs "^4.1.11"
+    micromatch "^3.1.10"
+    neo-async "^2.5.0"
+    node-dir "^0.1.17"
+    recast "^0.18.1"
+    temp "^0.8.1"
+    write-file-atomic "^2.3.0"
+
 jsdom@^11.5.1:
   version "11.12.0"
   resolved "https://registry.yarnpkg.com/jsdom/-/jsdom-11.12.0.tgz#1a80d40ddd378a1de59656e9e6dc5a3ba8657bc8"
@@ -11378,6 +11412,15 @@ react-is@^16.8.1, react-is@^16.8.4, react-is@^16.9.0:
   resolved "https://registry.yarnpkg.com/react-is/-/react-is-16.13.1.tgz#789729a4dc36de2999dc156dd6c1d9c18cea56a4"
   integrity sha512-24e6ynE2H+OKt4kqsOvNd8kBpV65zoxbA4BVsEOB3ARVWQki/DHzaUoC5KuON/BiccDaCCTZBuOcfZs70kR8bQ==
 
+react-native-codegen@0.0.2:
+  version "0.0.2"
+  resolved "https://registry.yarnpkg.com/react-native-codegen/-/react-native-codegen-0.0.2.tgz#2a1c15a9deb80b62a5e9c0f215bb29900216f7ee"
+  integrity sha512-cZ28TUlYanjpca6dcxyGmZi4JKTmeaE4vJhjTABMRD+R7Rw6FtTAUqU2BoAKksEsrf8dJN5pQEUOSb4Cv0502Q==
+  dependencies:
+    flow-parser "^0.121.0"
+    jscodeshift "^0.7.0"
+    nullthrows "^1.1.1"
+
 react-native-tscodegen@0.0.10:
   version "0.0.10"
   resolved "https://registry.yarnpkg.com/react-native-tscodegen/-/react-native-tscodegen-0.0.10.tgz#2997f039625e55aac91a367ac3d6b496c50f1265"
@@ -11591,6 +11634,16 @@ recast@^0.16.1:
     private "~0.1.5"
     source-map "~0.6.1"
 
+recast@^0.18.1:
+  version "0.18.10"
+  resolved "https://registry.yarnpkg.com/recast/-/recast-0.18.10.tgz#605ebbe621511eb89b6356a7e224bff66ed91478"
+  integrity sha512-XNvYvkfdAN9QewbrxeTOjgINkdY/odTgTS56ZNEWL9Ml0weT4T3sFtvnTuF+Gxyu46ANcRm1ntrF6F5LAJPAaQ==
+  dependencies:
+    ast-types "0.13.3"
+    esprima "~4.0.0"
+    private "^0.1.8"
+    source-map "~0.6.1"
+
 rechoir@^0.6.2:
   version "0.6.2"
   resolved "https://registry.yarnpkg.com/rechoir/-/rechoir-0.6.2.tgz#85204b54dba82d5742e28c96756ef43af50e3384"

From 328b820887c431050a8380a6751668b5ff775e31 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Wed, 22 Apr 2020 13:39:30 -0700
Subject: [PATCH 6/9] minor change

---
 .../codegen/NativeModules.g.h                 |  7 ++--
 .../package.json                              |  2 +-
 .../src/generators/GenerateNM2.ts             |  7 ++--
 yarn.lock                                     | 41 -------------------
 4 files changed, 9 insertions(+), 48 deletions(-)

diff --git a/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h b/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
index 5a6559c3cf3..22d7b869d01 100644
--- a/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
+++ b/packages/microsoft-reactnative-sampleapps/codegen/NativeModules.g.h
@@ -1,6 +1,6 @@
 
 /**
- * This file is auto-generated.
+ * This file is auto-generated from a NativeModule spec file in js.
  */
 
 #pragma once
@@ -11,8 +11,9 @@
 namespace SampleLibraryCpp {
 
 /*
- * This function registers a class as implementing a TurboModule Spec
- * The class must implement all the methods as required by the Spec.
+ * This is a C++ Spec class that should be used with MakeTurboModuleProvider to register native modules
+ * in a way that also verifies at compile time that the native module matches the interface required
+ * by the TurboModule JS spec.
  */
 struct MyModuleSpec : winrt::Microsoft::ReactNative::TurboModuleSpec {
   static constexpr auto methods = std::tuple{
diff --git a/packages/microsoft-reactnative-sampleapps/package.json b/packages/microsoft-reactnative-sampleapps/package.json
index 7eefaa8fd26..e202169c606 100644
--- a/packages/microsoft-reactnative-sampleapps/package.json
+++ b/packages/microsoft-reactnative-sampleapps/package.json
@@ -26,7 +26,7 @@
     "@types/react": "16.9.0",
     "@types/react-native": "^0.62.2",
     "just-scripts": "^0.36.1",
-    "metro-react-native-babel-preset": "0.56.0",
+    "metro-react-native-babel-preset": "^0.56.0",
     "react-native-windows-codegen": "0.0.1",
     "react-test-renderer": "16.9.0"
   }
diff --git a/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
index 4e63e324b5f..190e09c6821 100644
--- a/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
+++ b/packages/react-native-windows-codegen/src/generators/GenerateNM2.ts
@@ -19,8 +19,9 @@ type FilesOutput = Map<string, string>;
 
 const moduleTemplate = `
 /*
- * This function registers a class as implementing a TurboModule Spec
- * The class must implement all the methods as required by the Spec.
+ * This is a C++ Spec class that should be used with MakeTurboModuleProvider to register native modules
+ * in a way that also verifies at compile time that the native module matches the interface required
+ * by the TurboModule JS spec.
  */
 struct ::_MODULE_NAME_::Spec : winrt::Microsoft::ReactNative::TurboModuleSpec {
   static constexpr auto methods = std::tuple{
@@ -37,7 +38,7 @@ struct ::_MODULE_NAME_::Spec : winrt::Microsoft::ReactNative::TurboModuleSpec {
 
 const template = `
 /**
- * This file is auto-generated.
+ * This file is auto-generated from a NativeModule spec file in js.
  */
 
 #pragma once
diff --git a/yarn.lock b/yarn.lock
index fe1b4f80952..95232c8022e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -9570,47 +9570,6 @@ metro-minify-uglify@0.58.0:
   dependencies:
     uglify-es "^3.1.9"
 
-metro-react-native-babel-preset@0.56.0:
-  version "0.56.0"
-  resolved "https://registry.yarnpkg.com/metro-react-native-babel-preset/-/metro-react-native-babel-preset-0.56.0.tgz#fa47dfd5f7678e89cffd1249020b8add6938fc48"
-  integrity sha512-MAo1fm0dNn6MVZmylaz6k2HC1MINHLTLfE7O3a9Xz3fAtbGbApisp06rBUfK5uUqIJDmAaKgbiT34lHJSIiE6Q==
-  dependencies:
-    "@babel/plugin-proposal-class-properties" "^7.0.0"
-    "@babel/plugin-proposal-export-default-from" "^7.0.0"
-    "@babel/plugin-proposal-nullish-coalescing-operator" "^7.0.0"
-    "@babel/plugin-proposal-object-rest-spread" "^7.0.0"
-    "@babel/plugin-proposal-optional-catch-binding" "^7.0.0"
-    "@babel/plugin-proposal-optional-chaining" "^7.0.0"
-    "@babel/plugin-syntax-dynamic-import" "^7.0.0"
-    "@babel/plugin-syntax-export-default-from" "^7.0.0"
-    "@babel/plugin-syntax-flow" "^7.2.0"
-    "@babel/plugin-transform-arrow-functions" "^7.0.0"
-    "@babel/plugin-transform-block-scoping" "^7.0.0"
-    "@babel/plugin-transform-classes" "^7.0.0"
-    "@babel/plugin-transform-computed-properties" "^7.0.0"
-    "@babel/plugin-transform-destructuring" "^7.0.0"
-    "@babel/plugin-transform-exponentiation-operator" "^7.0.0"
-    "@babel/plugin-transform-flow-strip-types" "^7.0.0"
-    "@babel/plugin-transform-for-of" "^7.0.0"
-    "@babel/plugin-transform-function-name" "^7.0.0"
-    "@babel/plugin-transform-literals" "^7.0.0"
-    "@babel/plugin-transform-modules-commonjs" "^7.0.0"
-    "@babel/plugin-transform-object-assign" "^7.0.0"
-    "@babel/plugin-transform-parameters" "^7.0.0"
-    "@babel/plugin-transform-react-display-name" "^7.0.0"
-    "@babel/plugin-transform-react-jsx" "^7.0.0"
-    "@babel/plugin-transform-react-jsx-source" "^7.0.0"
-    "@babel/plugin-transform-regenerator" "^7.0.0"
-    "@babel/plugin-transform-runtime" "^7.0.0"
-    "@babel/plugin-transform-shorthand-properties" "^7.0.0"
-    "@babel/plugin-transform-spread" "^7.0.0"
-    "@babel/plugin-transform-sticky-regex" "^7.0.0"
-    "@babel/plugin-transform-template-literals" "^7.0.0"
-    "@babel/plugin-transform-typescript" "^7.0.0"
-    "@babel/plugin-transform-unicode-regex" "^7.0.0"
-    "@babel/template" "^7.0.0"
-    react-refresh "^0.4.0"
-
 metro-react-native-babel-preset@0.58.0:
   version "0.58.0"
   resolved "https://registry.yarnpkg.com/metro-react-native-babel-preset/-/metro-react-native-babel-preset-0.58.0.tgz#18f48d33fe124280ffabc000ab8b42c488d762a2"

From 3d3e5acf59e07e9fd0e91d78d27fda575d637061 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Wed, 22 Apr 2020 13:42:36 -0700
Subject: [PATCH 7/9] minor change

---
 packages/microsoft-reactnative-sampleapps/package.json | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/microsoft-reactnative-sampleapps/package.json b/packages/microsoft-reactnative-sampleapps/package.json
index e202169c606..1d4ebd0d403 100644
--- a/packages/microsoft-reactnative-sampleapps/package.json
+++ b/packages/microsoft-reactnative-sampleapps/package.json
@@ -7,7 +7,6 @@
     "bundle-cpp": "just-scripts prepareBundle && react-native bundle --platform windows --entry-file index.windows.js --bundle-output windows/SampleAppCpp/Bundle/index.windows.bundle --assets-dest windows/SampleAppCpp/Bundle",
     "bundle-cs": "just-scripts prepareBundle && react-native bundle --platform windows --entry-file index.windows.js --bundle-output windows/SampleAppCS/Bundle/index.windows.bundle --assets-dest windows/SampleAppCS/Bundle",
     "clean": "just-scripts clean",
-    "codegen": "react-native-windows-codegen --file NativeMyModule.js --namespace SampleLibraryCpp",
     "start": "react-native start",
     "lint": "just-scripts lint",
     "lint:fix": "just-scripts lint:fix",

From 7cf0a57a04f387e20865fd01d8772d236d9e4952 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Wed, 22 Apr 2020 13:47:54 -0700
Subject: [PATCH 8/9] minor changes

---
 packages/microsoft-reactnative-sampleapps/index.windows.js | 1 -
 1 file changed, 1 deletion(-)

diff --git a/packages/microsoft-reactnative-sampleapps/index.windows.js b/packages/microsoft-reactnative-sampleapps/index.windows.js
index 3da9c211313..6adf5cdaf99 100644
--- a/packages/microsoft-reactnative-sampleapps/index.windows.js
+++ b/packages/microsoft-reactnative-sampleapps/index.windows.js
@@ -14,7 +14,6 @@ import {
   UIManager,
   View,
   Linking,
-  Alert,
 } from 'react-native';
 
 import { NativeModules, NativeEventEmitter } from 'react-native';

From 08f8d143702205558a1ac975c0f91b0c845e5d74 Mon Sep 17 00:00:00 2001
From: "Andrew Coates (REDMOND)" <acoates@microsoft.com>
Date: Wed, 22 Apr 2020 13:49:54 -0700
Subject: [PATCH 9/9] Change files

---
 ...ve-windows-codegen-2020-04-22-13-49-54-codegennm2.json | 8 ++++++++
 1 file changed, 8 insertions(+)
 create mode 100644 change/react-native-windows-codegen-2020-04-22-13-49-54-codegennm2.json

diff --git a/change/react-native-windows-codegen-2020-04-22-13-49-54-codegennm2.json b/change/react-native-windows-codegen-2020-04-22-13-49-54-codegennm2.json
new file mode 100644
index 00000000000..6d75f195f59
--- /dev/null
+++ b/change/react-native-windows-codegen-2020-04-22-13-49-54-codegennm2.json
@@ -0,0 +1,8 @@
+{
+  "type": "patch",
+  "comment": "Initial react-native-windows-codegen",
+  "packageName": "react-native-windows-codegen",
+  "email": "acoates@microsoft.com",
+  "dependentChangeType": "patch",
+  "date": "2020-04-22T20:49:54.580Z"
+}