Summary: Two documentation errors in `scripts/js-api/README.md`: 1. **Wrong link text** (line 22): The link for the Flow-to-TypeScript converter reads `[flow-api-extractor](https://www.npmjs.com/package/flow-api-translator)` but the package name is `flow-api-translator`, not `flow-api-extractor`. The link URL was correct but the visible text was misleading. 2. **Wrong filename** (line 76): The Public API snapshot section refers to the file as `ReactNative.d.ts`, while the actual file committed to the repo is `ReactNativeApi.d.ts`. The correct name is already used earlier in the same document (line 16 and line 41). Fixes https://github.com/facebook/react-native/issues/55667 Fixes https://github.com/facebook/react-native/issues/55668 ## Changelog: [General] [Fixed] - Fix incorrect package name and output filename in scripts/js-api/README.md Pull Request resolved: https://github.com/facebook/react-native/pull/56362 Test Plan: Documentation-only change. Verified the link URL and the actual file name at `packages/react-native/ReactNativeApi.d.ts`. Reviewed By: huntie Differential Revision: D100761759 Pulled By: cortinico fbshipit-source-id: 8a30ca1a5f35c9491c2ad4c94ae20da4621cb5a7
scripts/js-api
TypeScript build pipeline for React Native's JavaScript API.
Overview
yarn build-types is a custom build pipeline for translating React Native's Flow source code to TypeScript.
Specifically, it reduces the runtime JavaScript API of react-native into two outputs:
- Generated TypeScript types
Public user types for react-native, shipped to npm
packages/react-native/types_generated/ - Public API snapshot
Snapshot file of the public API shape, used by maintainers
packages/react-native/ReactNativeApi.d.ts
Dependencies
yarn build-types makes use of the following dependencies, composed with other pre/post transformation steps and dependency resolution.
- Flow → TypeScript conversion: flow-api-translator
- TypeScript → (initial) API rollup: @microsoft/api-extractor
Usage
Build generated types + API snapshot
Maintainers should run this script whenever making intentional API changes.
# Build types + API snapshot
yarn build-types [--validate]
# Build types without API snapshot
yarn build-types --skip-snapshot
Diff API snapshot compatibility
This script is run by CI to compare changes to ReactNativeApi.d.ts between commits.
# Compare two versions of the API snapshot
yarn js-api-diff <before.d.ts> <after.d.ts>
{
"result": "BREAKING",
"changedApis": [
"ViewStyle"
]
}
Configuration
Sparse configuration options are defined and documented in scripts/js-api/config.js.
About the two output formats
Generated TypeScript types
types_generated/
Directory providing TypeScript user types for the react-native package, distributed via npm.
- Gitignored.
- Scoped to the
index.d.tsentry point viapackage.json#exports. - Preserves
unstable_andexperimental_APIs. - Preserves doc comments.
- Preserves source file names (for go to definition).
Public API snapshot
ReactNativeApi.d.ts
Provides a human-readable, maintainable reference of the React Native's public JavaScript API, optimized for developers and diff tooling.
- Committed to the repo.
- Strips
unstable_andexperimental_APIs. - Strips doc comments.
- Strips source file names (types are merged into a single program).
- Versions exported APIs with an 8 char SHA hash, which will be updated when any input type dependencies change shape.