[CLI] Support Hermes (microsoft#5)

This PR adds support of Hermes for the code-push cli.
It will try checking if hermes is enabled in the build.gradle or Podfile
and run the hermes compiler if it is enabled.

Author: DmitriyKirakosyan

cli/README.md

@@ -392,6 +392,9 @@ code-push-standalone release-react <appName> <platform>
 [--sourcemapOutput <sourcemapOutput>]
 [--targetBinaryVersion <targetBinaryVersion>]
 [--rollout <rolloutPercentage>]
+[--useHermes <useHermes>]
+[--podFile <podFile>]
+[--extraHermesFlags <extraHermesFlags>]
 ```
 
 The `release-react` command is a React Native-specific version of the "vanilla" [`release`](#releasing-app-updates) command, which supports all of the same parameters (e.g. `--mandatory`, `--description`), yet simplifies the process of releasing updates by performing the following additional behavior:
@@ -521,6 +524,24 @@ This specifies the relative path to where the assets, JS bundle and sourcemap fi
 
 _NOTE: This parameter can be set using either --outputDir or -o_
 
+#### Use Hermes parameter
+
+This parameter enforces the use of the Hermes compiler. If not specified, the automatic checks will be performed, inspecting the `build.gradle` and `Podfile` for the Hermes flag.
+
+_NOTE: This parameter can be set using either --hermesEnabled or -h_
+
+#### Podfile parameter (iOS only)
+
+The Podfile path will be used for Hermes automatic check. Not used if `--useHermes` is specified.
+
+_NOTE: This parameter can be set using either --podfile or -pod_
+
+#### Extra hermes flags parameter
+
+Hermes flags which will be passed to Hermes compiler.
+
+_NOTE: This parameter can be set using either --extraHermesFlags or -hf_
+
 ## Debugging CodePush Integration
 
 Once you've released an update, React Native plugin has been integrated into your app, it can be helpful to diagnose how the plugin is behaving, especially if you run into an issue and want to understand why. In order to debug the CodePush update discovery experience, you can run the following command in order to easily view the diagnostic logs produced by the CodePush plugin within your app:

cli/script/command-executor.ts

@@ -36,6 +36,12 @@ import {
   Session,
   UpdateMetrics,
 } from "../script/types";
+import {
+  fileDoesNotExistOrIsDirectory,
+  getAndroidHermesEnabled,
+  getiOSHermesEnabled,
+  runHermesEmitBinaryCommand
+} from "./react-native-utils";
 
 const configFilePath: string = path.join(process.env.LOCALAPPDATA || process.env.HOME, ".code-push.config");
 const emailValidator = require("email-validator");
@@ -550,14 +556,6 @@ export function execute(command: cli.ICommand) {
   });
 }
 
-function fileDoesNotExistOrIsDirectory(filePath: string): boolean {
-  try {
-    return fs.lstatSync(filePath).isDirectory();
-  } catch (error) {
-    return true;
-  }
-}
-
 function getTotalActiveFromDeploymentMetrics(metrics: DeploymentMetrics): number {
   let totalActive = 0;
   Object.keys(metrics).forEach((label: string) => {
@@ -1307,6 +1305,24 @@ export const releaseReact = (command: cli.IReleaseReactCommand): Promise<void> =
           command.sourcemapOutput
         )
       )
+      .then(async () => {
+        const isHermesEnabled =
+        command.useHermes ||
+        (platform === "android" && (await getAndroidHermesEnabled(command.gradleFile))) || // Check if we have to run hermes to compile JS to Byte Code if Hermes is enabled in build.gradle and we're releasing an Android build
+        (platform === "ios" && (await getiOSHermesEnabled(command.podFile))); // Check if we have to run hermes to compile JS to Byte Code if Hermes is enabled in Podfile and we're releasing an iOS build
+
+        if (isHermesEnabled) {
+          log(chalk.cyan("\nRunning hermes compiler...\n"));
+          await runHermesEmitBinaryCommand(
+            bundleName,
+            outputFolder,
+            command.sourcemapOutput,
+            command.extraHermesFlags,
+            command.gradleFile
+          );
+        }
+
+      })
       .then(() => {
         log(chalk.cyan("\nReleasing update contents to CodePush:\n"));
         return release(releaseCommand);

cli/script/command-parser.ts

@@ -775,6 +775,28 @@ yargs
           "Path to where the bundle and sourcemap should be written. If omitted, a bundle and sourcemap will not be written.",
         type: "string",
       })
+      .option("useHermes", {
+        alias: "h",
+        default: false,
+        demand: false,
+        description: "Enable hermes and bypass automatic checks",
+        type: "boolean",
+      })
+      .option("podFile", {
+        alias: "pod",
+        default: null,
+        demand: false,
+        description:  "Path to the cocopods config file (iOS only).",
+        type: "string",
+      })
+      .option("extraHermesFlags", {
+        alias: "hf",
+        default: [],
+        demand: false,
+        description:
+          "Flags that get passed to Hermes, JavaScript to bytecode compiler. Can be specified multiple times.",
+        type: "array",
+      })
       .check((argv: any, aliases: { [aliases: string]: string }): any => {
         return checkValidReleaseOptions(argv);
       });
@@ -1169,6 +1191,9 @@ export function createCommand(): cli.ICommand {
           releaseReactCommand.rollout = getRolloutValue(argv["rollout"] as any);
           releaseReactCommand.sourcemapOutput = argv["sourcemapOutput"] as any;
           releaseReactCommand.outputDir = argv["outputDir"] as any;
+          releaseReactCommand.useHermes = argv["useHermes"] as any;
+          releaseReactCommand.extraHermesFlags = argv["extraHermesFlags"] as any;
+          releaseReactCommand.podFile = argv["podFile"] as any;
         }
         break;