Expose build entry point for AssetRegistry (#57232)

Summary:
Pull Request resolved: #57232

**Problem**

Following D108750303, we now expose an `AssetsRegistry` API from `'react-native'`.

This is great, as we need to replace a deep `/Libraries/...` import in Metro configs (`transformer.assetRegistryPath`):

https://www.internalfb.com/code/fbsource/[31661d52e803d77356725429f44331135601b634]/xplat/js/react-native-github/packages/metro-config/src/index.flow.js?lines=87

**Unfortunately**, we can't quite reuse the new `AssetRegistry` API from the index module, as we'd break Metro's API contract (generate an inline require) — we need a dedicated wrapper module that can be read without destructuring.

**This diff**

Adds a new `'react-native/asset-registry'` secondary entry point, intended/documented for this Metro config use case — and deprecates `react-native/assets-registry/registry`.

- Solves the above problem (migrated in our own `react-native/metro-config` use).
- Remains consistent with D108750302 (we intend to remove `react-native/assets-registry` at a later date).
- As a bonus, fixes the longstanding naming inconsistency between `react-native/assets-registry` and `'react-native/Libraries/Image/AssetRegistry'` — `AssetRegistry` (singular) is now canonical.

Changelog:
- [General][Breaking] - `react-native/Libraries/Image/AssetRegistry` is removed. Please use the `AssetRegistry` API (apps/library code) and/or the `react-native/asset-registry` entrypoint (Metro/build configs).
- [General][Deprecated] - **assets-registry**: `react-native/assets-registry/registry` is deprecated. Please use the `AssetRegistry` API (apps/library code) and/or the `react-native/asset-registry` entrypoint (Metro/build configs).

Reviewed By: javache

Differential Revision: D108750303

Author: huntie

packages/assets-registry/README.md

@@ -11,10 +11,14 @@ Most apps never import this directly — assets are handled through `<Image>`.
 
 ## API
 
-### `@react-native/assets-registry/registry`
-
-> [!Note]
-> Aliases to [`AssetRegistry`](https://reactnative.dev/docs/assetregistry) (since 0.87). Prefer importing directly from the `'react-native'` package in libraries.
+### `@react-native/assets-registry/registry` (DEPRECATED)
+
+> [!Warning]
+> **Deprecated**: Aliases to [`AssetRegistry`](https://reactnative.dev/docs/assetregistry) (since 0.87).
+>
+> Please use:
+> - `import { AssetRegistry } from 'react-native';` (apps/library code)
+> - `'react-native/asset-registry'` (entrypoint for Metro/build configs)
 
 | Export | Signature | Notes |
 |---|---|---|

packages/assets-registry/registry.d.ts

@@ -7,8 +7,14 @@
  * @format
  */
 
+/**
+ * @deprecated Use `import type {AssetDestPathResolver} from 'react-native'` instead.
+ */
 export type AssetDestPathResolver = 'android' | 'generic';
 
+/**
+ * @deprecated Use `import type {PackagerAsset} from 'react-native'` instead.
+ */
 export type PackagerAsset = {
   readonly __packager_asset: boolean;
   readonly fileSystemLocation: string;
@@ -22,6 +28,12 @@ export type PackagerAsset = {
   readonly resolver?: AssetDestPathResolver | undefined;
 };
 
+/**
+ * @deprecated Use `import {AssetRegistry} from 'react-native'` instead.
+ */
 export function registerAsset(asset: PackagerAsset): number;
 
+/**
+ * @deprecated Use `import {AssetRegistry} from 'react-native'` instead.
+ */
 export function getAssetByID(assetId: number): PackagerAsset;

packages/eslint-plugin-react-native/no-deep-imports.js

@@ -32,6 +32,7 @@ module.exports = {
         if (
           !isDeepReactNativeImport(node.source) ||
           isInitializeCoreImport(node.source) ||
+          isSecondaryEntryPoint(node.source) ||
           isFbInternalImport(node.source)
         ) {
           return;
@@ -88,6 +89,7 @@ module.exports = {
         if (
           !isDeepRequire(node) ||
           isInitializeCoreImport(node.arguments[0]) ||
+          isSecondaryEntryPoint(node.arguments[0]) ||
           isFbInternalImport(node.arguments[0])
         ) {
           return;
@@ -173,6 +175,14 @@ module.exports = {
       return source.value === 'react-native/Libraries/Core/InitializeCore';
     }
 
+    function isSecondaryEntryPoint(source) {
+      if (source.type !== 'Literal' || typeof source.value !== 'string') {
+        return false;
+      }
+
+      return source.value === 'react-native/asset-registry';
+    }
+
     function isFbInternalImport(source) {
       if (source.type !== 'Literal' || typeof source.value !== 'string') {
         return false;

packages/metro-config/src/index.flow.js

@@ -84,7 +84,7 @@ export function getDefaultConfig(projectRoot: string): ConfigT {
     },
     transformer: {
       allowOptionalDependencies: true,
-      assetRegistryPath: 'react-native/Libraries/Image/AssetRegistry',
+      assetRegistryPath: 'react-native/asset-registry',
       asyncRequireModulePath: require.resolve(
         'metro-runtime/src/modules/asyncRequire',
       ),

packages/react-native/Libraries/Image/AssetRegistry.js

@@ -56,6 +56,10 @@
       "react-native-strict-api": null,
       "default": "./types/*.d.ts"
     },
+    "./asset-registry": {
+      "types": null,
+      "default": "./src/asset-registry.js"
+    },
     "./jest-preset": "./jest-preset.js",
     "./rn-get-polyfills": "./rn-get-polyfills.js",
     "./src/fb_internal/*": "./src/fb_internal/*",

packages/react-native/package.json

@@ -0,0 +1,27 @@
+/**
+ * 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 strict-local
+ * @format
+ */
+
+// ----------------------------------------------------------------------------
+// Secondary react-native/asset-registry entry point.
+//
+// This is an untyped secondary entry point intended to be referenced from
+// Metro's `transformer.assetRegistryPath` config option. This entry point may
+// also be preferred in server-side code.
+//
+// Apps/libraries should use `import {AssetRegistry} from 'react-native'`.
+// ----------------------------------------------------------------------------
+
+import {AssetRegistry} from './private/assets/AssetRegistry';
+
+/* eslint-disable @react-native/monorepo/no-commonjs-exports */
+module.exports = {
+  registerAsset: AssetRegistry.registerAsset,
+  getAssetByID: AssetRegistry.getAssetByID,
+};