react-native/scripts/build-types/BuildApiSnapshot.js

/**
 * 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
 * @format
 * @oncall react_native
 */

import type {PluginObj} from '@babel/core';

const {PACKAGES_DIR, REACT_NATIVE_PACKAGE_DIR} = require('../consts');
const {API_EXTRACTOR_CONFIG_FILE, TYPES_OUTPUT_DIR} = require('./config');
const apiSnapshotTemplate = require('./templates/ReactNativeApi.d.ts-template.js');
const resolveCyclicImportsInDefinition = require('./transforms/resolveCyclicImportsInDefinition');
const babel = require('@babel/core');
const {
  Extractor,
  ExtractorConfig,
  // $FlowFixMe[cannot-resolve-module]
} = require('@microsoft/api-extractor');
const {promises: fs} = require('fs');
const glob = require('glob');
const path = require('path');
const prettier = require('prettier');
const osTempDir = require('temp-dir');

const inputFilesPostTransforms: $ReadOnlyArray<PluginObj<mixed>> = [
  require('./transforms/renameDefaultExportedIdentifiers'),
];

const postTransforms: $ReadOnlyArray<PluginObj<mixed>> = [
  require('./transforms/sortTypeDefinitions'),
  require('./transforms/sortProperties'),
  require('./transforms/sortUnions'),
];

async function buildAPISnapshot() {
  const tempDirectory = await createTempDir('react-native-js-api-snapshot');
  const packages = await findPackagesWithTypedef();

  await preparePackagesInTempDir(tempDirectory, packages);
  await rewriteLocalImports(tempDirectory, packages);

  const extractorConfig = ExtractorConfig.loadFileAndPrepare(
    path.join(tempDirectory, API_EXTRACTOR_CONFIG_FILE),
  );

  const extractorResult = Extractor.invoke(extractorConfig, {
    localBuild: true,
    showVerboseMessages: true,
  });

  if (extractorResult.succeeded) {
    const apiSnapshot = apiSnapshotTemplate(
      await getCleanedUpRollup(tempDirectory),
    );

    await fs.writeFile(
      path.join(REACT_NATIVE_PACKAGE_DIR, 'ReactNativeApi.d.ts'),
      apiSnapshot,
    );
  } else {
    process.exitCode = 1;
    console.error(
      `API Extractor failed with ${extractorResult.errorCount} errors` +
        ` and ${extractorResult.warningCount} warnings`,
    );
  }

  await fs.rm(tempDirectory, {recursive: true});
}

async function findPackagesWithTypedef() {
  const packagesWithGeneratedTypes = glob
    .sync(`${PACKAGES_DIR}/**/types_generated`, {nodir: false})
    .map(typesPath =>
      path.relative(PACKAGES_DIR, typesPath).split('/').slice(0, -1).join('/'),
    );

  const packagesWithNames = await Promise.all(
    packagesWithGeneratedTypes.map(async pkg => {
      const packageJsonContent = await fs.readFile(
        path.join(PACKAGES_DIR, pkg, 'package.json'),
        'utf-8',
      );
      const packageJson = JSON.parse(packageJsonContent);

      return {
        directory: pkg,
        name: packageJson.name as string,
      };
    }),
  );

  return packagesWithNames;
}

async function preparePackagesInTempDir(
  tempDirectory: string,
  packages: $ReadOnlyArray<{directory: string, name: string}>,
) {
  await generateConfigFiles(tempDirectory);

  await Promise.all(
    packages.map(async pkg => {
      await copyDirectory(
        path.join(PACKAGES_DIR, pkg.directory, TYPES_OUTPUT_DIR),
        path.join(tempDirectory, pkg.directory),
      );
    }),
  );

  const typeDefs = glob.sync(`${tempDirectory}/**/*.d.ts`);
  await Promise.all(
    typeDefs.map(async file => {
      const source = await fs.readFile(file, 'utf-8');
      const transformed = await applyPostTransforms(
        source,
        inputFilesPostTransforms,
      );
      await fs.writeFile(file, transformed);
    }),
  );
}

/**
 * Rewrite imports to local packages in the temp directory. We do this to
 * avoid cyclic references, which API Extractor cannot process.
 */
async function rewriteLocalImports(
  tempDirectory: string,
  packages: $ReadOnlyArray<{directory: string, name: string}>,
) {
  const definitions = glob.sync(`${tempDirectory}/**/*.d.ts`);

  await Promise.all(
    definitions.map(async file => {
      const source = await fs.readFile(file, 'utf-8');
      const fixedImports = await resolveCyclicImportsInDefinition({
        packages: packages,
        rootPath: tempDirectory,
        sourcePath: file,
        source: source,
      });
      await fs.writeFile(file, fixedImports);
    }),
  );
}

async function getCleanedUpRollup(tempDirectory: string) {
  const rollupPath = path.join(
    tempDirectory,
    'react-native',
    'dist',
    'api-rollup.d.ts',
  );
  const sourceRollup = await fs.readFile(rollupPath, 'utf-8');

  const cleanedRollup = sourceRollup
    .replace(/\/\*[\s\S]*?\*\//gm, '') // Remove block comments
    .replace(/\\\\.*$/gm, '') // Remove inline comments
    .replace(/^\s+$/gm, '') // Clear whitespace-only lines
    .replace(/\n+/gm, '\n'); // Collapse empty lines

  const transformedRollup = await applyPostTransforms(
    cleanedRollup,
    postTransforms,
  );

  const formattedRollup = prettier.format(transformedRollup, {
    parser: 'typescript',
  });

  return formattedRollup;
}

async function applyPostTransforms(
  inSrc: string,
  transforms: $ReadOnlyArray<PluginObj<mixed>>,
): Promise<string> {
  const result = await babel.transformAsync(inSrc, {
    plugins: ['@babel/plugin-syntax-typescript', ...transforms],
  });

  return result.code;
}

async function generateConfigFiles(tempDirectory: string) {
  // generate tsconfig
  const tsConfig = {
    $schema: 'http://json.schemastore.org/tsconfig',
  };

  const outPath = path.join(tempDirectory, 'tsconfig.json');

  await fs.mkdir(path.dirname(outPath), {recursive: true});
  await fs.writeFile(outPath, JSON.stringify(tsConfig, null, 2));

  // generate api extractor config
  const apiExtractorConfig = await fs.readFile(
    path.join(__dirname, 'templates', API_EXTRACTOR_CONFIG_FILE),
    'utf-8',
  );
  const adjustedApiExtractorConfig = apiExtractorConfig.replaceAll(
    '${typegen_directory}',
    tempDirectory,
  );
  await fs.writeFile(
    path.join(tempDirectory, API_EXTRACTOR_CONFIG_FILE),
    adjustedApiExtractorConfig,
  );

  // generate basic package.json
  const packageJSON = {name: 'react-native'};
  await fs.writeFile(
    path.join(tempDirectory, 'package.json'),
    JSON.stringify(packageJSON, null, 2),
  );
}

async function copyDirectory(src: string, dest: string) {
  await fs.mkdir(dest, {recursive: true});

  const entries = await fs.readdir(src, {withFileTypes: true});

  for (let entry of entries) {
    // name can only be a buffer when explicitly set as the encoding option
    const fileName: string = entry.name as any;
    const srcPath = path.join(src, fileName);
    const destPath = path.join(dest, fileName);

    if (entry.isDirectory()) {
      await copyDirectory(srcPath, destPath);
    } else {
      await fs.copyFile(srcPath, destPath);
    }
  }
}

async function createTempDir(dirName: string): Promise<string> {
  // $FlowExpectedError[incompatible-call] temp-dir is typed as a default export
  const tempDir = path.join(osTempDir, dirName);

  await fs.mkdir(tempDir, {recursive: true});

  return tempDir;
}

module.exports = buildAPISnapshot;