feat (doctor): add packager healthcheck to report if packager is running correctly

packages/cli-doctor/src/tools/healthchecks/index.ts

@@ -14,6 +14,7 @@ import iosDeploy from './iosDeploy';
 import {Healthchecks, HealthCheckCategory} from '../../types';
 import loadConfig from '@react-native-community/cli-config';
 import xcodeEnv from './xcodeEnv';
+import packager from './packager';
 
 export const HEALTHCHECK_TYPES = {
   ERROR: 'ERROR',
@@ -41,6 +42,7 @@ export const getHealthchecks = ({contributor}: Options): Healthchecks => {
         nodeJS,
         yarn,
         npm,
+        packager,
         ...(process.platform === 'darwin' ? [watchman] : []),
       ],
     },

packages/cli-doctor/src/tools/healthchecks/packager.ts

@@ -0,0 +1,51 @@
+import {
+  getDefaultUserTerminal,
+  isPackagerRunning,
+} from '@react-native-community/cli-tools';
+import {HealthCheckInterface} from '../../types';
+import {logManualInstallation} from './common';
+import {startServerInNewWindow} from '@react-native-community/cli-platform-android';
+
+export default {
+  label: 'Metro',
+  isRequired: false,
+  description: 'Required for bundling the JavaScript code',
+  getDiagnostics: async () => {
+    const status = await isPackagerRunning();
+    const needsToBeFixed = status === 'not_running';
+    if (needsToBeFixed) {
+      return {
+        description: 'Metro Bundler is not running',
+        needsToBeFixed,
+      };
+    }
+    return {
+      needsToBeFixed,
+    };
+  },
+  runAutomaticFix: async ({loader, config}) => {
+    loader.fail();
+    try {
+      const terminal = getDefaultUserTerminal();
+      const port = Number(process.env.RCT_METRO_PORT) || 8081;
+      if (terminal && config) {
+        startServerInNewWindow(
+          port,
+          terminal,
+          config.root,
+          config.reactNativePath,
+        );
+        return loader.succeed();
+      }
+      return logManualInstallation({
+        message:
+          'Could not start the packager. Please run "react-native start" command manually.',
+      });
+    } catch (error) {
+      return logManualInstallation({
+        message:
+          'Could not start the packager. Please run "react-native start" command manually.',
+      });
+    }
+  },
+} as HealthCheckInterface;

packages/cli-platform-android/src/index.ts

@@ -11,3 +11,4 @@ export {
 } from './commands/runAndroid';
 export {projectConfig, dependencyConfig} from './config';
 export {getAndroidProject, getPackageName} from './config/getAndroidProject';
+export {startServerInNewWindow} from './commands/buildAndroid/startServerInNewWindow';