RFC: Add @react-native/metro-config package

packages/metro-config/index.js

@@ -0,0 +1,86 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow
+ * @noformat
+ */
+
+/*:: import type {ConfigT} from 'metro-config'; */
+
+const {getDefaultConfig: getBaseConfig, mergeConfig} = require('metro-config');
+
+const INTERNAL_CALLSITES_REGEX = new RegExp(
+  [
+    '/Libraries/Renderer/implementations/.+\\.js$',
+    '/Libraries/BatchedBridge/MessageQueue\\.js$',
+    '/Libraries/YellowBox/.+\\.js$',
+    '/Libraries/LogBox/.+\\.js$',
+    '/Libraries/Core/Timers/.+\\.js$',
+    '/Libraries/WebSocket/.+\\.js$',
+    '/Libraries/vendor/.+\\.js$',
+    '/node_modules/react-devtools-core/.+\\.js$',
+    '/node_modules/react-refresh/.+\\.js$',
+    '/node_modules/scheduler/.+\\.js$',
+    '/node_modules/event-target-shim/.+\\.js$',
+    '/node_modules/invariant/.+\\.js$',
+    '/node_modules/react-native/index.js$',
+    '/metro-runtime/.+\\.js$',
+    '^\\[native code\\]$',
+  ].join('|'),
+);
+
+/**
+ * Get the base Metro configuration for a React Native project.
+ */
+function getDefaultConfig(
+  projectRoot /*: string */
+) /*: ConfigT */ {
+  const config = {
+    resolver: {
+      resolverMainFields: ['react-native', 'browser', 'main'],
+      platforms: ['android', 'ios'],
+      unstable_conditionNames: ['import', 'require', 'react-native'],
+    },
+    serializer: {
+      getPolyfills: () => require('@react-native/js-polyfills')(),
+    },
+    server: {
+      port: Number(process.env.RCT_METRO_PORT) || 8081,
+    },
+    symbolicator: {
+      customizeFrame: (frame /*: $ReadOnly<{file: ?string, ...}>*/) => {
+        const collapse = Boolean(
+          frame.file && INTERNAL_CALLSITES_REGEX.test(frame.file),
+        );
+        return {collapse};
+      },
+    },
+    transformer: {
+      allowOptionalDependencies: true,
+      assetRegistryPath: 'react-native/Libraries/Image/AssetRegistry',
+      asyncRequireModulePath: require.resolve(
+        'metro-runtime/src/modules/asyncRequire',
+      ),
+      babelTransformerPath: require.resolve(
+        'metro-react-native-babel-transformer',
+      ),
+      getTransformOptions: async () => ({
+        transform: {
+          experimentalImportSupport: false,
+          inlineRequires: true,
+        },
+      }),
+    },
+    watchFolders: [],
+  };
+
+  return mergeConfig(
+    getBaseConfig.getDefaultValues(projectRoot),
+    config,
+  );
+}
+
+module.exports = {getDefaultConfig};

packages/metro-config/package.json

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+{
+  "name": "@react-native/metro-config",
+  "version": "0.72.0",
+  "description": "Metro configuration for React Native.",
+  "repository": {
+    "type": "git",
+    "url": "git@github.com:facebook/react-native.git",
+    "directory": "packages/metro-config"
+  },
+  "license": "MIT",
+  "exports": "./index.js",
+  "dependencies": {
+    "@react-native/js-polyfills": "^0.72.1",
+    "metro-config": "0.75.1"
+  }
+}