/** * Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved. * * This source code is licensed under the MIT license found in the * LICENSE file in the root directory of this source tree. */ /// import { EventEmitter } from 'events'; import type { Config } from '@jest/types'; import H from './constants'; import HasteFS from './HasteFS'; import HasteModuleMap, { SerializableModuleMap as HasteSerializableModuleMap } from './ModuleMap'; import type { ChangeEvent, HasteRegExp, InternalHasteMap, HasteMap as InternalHasteMapObject } from './types'; declare type HType = typeof H; declare type Options = { cacheDirectory?: string; computeDependencies?: boolean; computeSha1?: boolean; console?: Console; dependencyExtractor?: string | null; extensions: Array; forceNodeFilesystemAPI?: boolean; hasteImplModulePath?: string; ignorePattern?: HasteRegExp; maxWorkers: number; mocksPattern?: string; name: string; platforms: Array; providesModuleNodeModules?: Array; resetCache?: boolean; retainAllFiles: boolean; rootDir: string; roots: Array; skipPackageJson?: boolean; throwOnModuleCollision?: boolean; useWatchman?: boolean; watch?: boolean; }; declare namespace HasteMap { type ModuleMap = HasteModuleMap; type SerializableModuleMap = HasteSerializableModuleMap; type FS = HasteFS; type HasteMapObject = InternalHasteMapObject; type HasteChangeEvent = ChangeEvent; } /** * HasteMap is a JavaScript implementation of Facebook's haste module system. * * This implementation is inspired by https://github.com/facebook/node-haste * and was built with for high-performance in large code repositories with * hundreds of thousands of files. This implementation is scalable and provides * predictable performance. * * Because the haste map creation and synchronization is critical to startup * performance and most tasks are blocked by I/O this class makes heavy use of * synchronous operations. It uses worker processes for parallelizing file * access and metadata extraction. * * The data structures created by `jest-haste-map` can be used directly from the * cache without further processing. The metadata objects in the `files` and * `map` objects contain cross-references: a metadata object from one can look * up the corresponding metadata object in the other map. Note that in most * projects, the number of files will be greater than the number of haste * modules one module can refer to many files based on platform extensions. * * type HasteMap = { * clocks: WatchmanClocks, * files: {[filepath: string]: FileMetaData}, * map: {[id: string]: ModuleMapItem}, * mocks: {[id: string]: string}, * } * * // Watchman clocks are used for query synchronization and file system deltas. * type WatchmanClocks = {[filepath: string]: string}; * * type FileMetaData = { * id: ?string, // used to look up module metadata objects in `map`. * mtime: number, // check for outdated files. * size: number, // size of the file in bytes. * visited: boolean, // whether the file has been parsed or not. * dependencies: Array, // all relative dependencies of this file. * sha1: ?string, // SHA-1 of the file, if requested via options. * }; * * // Modules can be targeted to a specific platform based on the file name. * // Example: platform.ios.js and Platform.android.js will both map to the same * // `Platform` module. The platform should be specified during resolution. * type ModuleMapItem = {[platform: string]: ModuleMetaData}; * * // * type ModuleMetaData = { * path: string, // the path to look up the file object in `files`. * type: string, // the module type (either `package` or `module`). * }; * * Note that the data structures described above are conceptual only. The actual * implementation uses arrays and constant keys for metadata storage. Instead of * `{id: 'flatMap', mtime: 3421, size: 42, visited: true, dependencies: []}` the real * representation is similar to `['flatMap', 3421, 42, 1, []]` to save storage space * and reduce parse and write time of a big JSON blob. * * The HasteMap is created as follows: * 1. read data from the cache or create an empty structure. * * 2. crawl the file system. * * empty cache: crawl the entire file system. * * cache available: * * if watchman is available: get file system delta changes. * * if watchman is unavailable: crawl the entire file system. * * build metadata objects for every file. This builds the `files` part of * the `HasteMap`. * * 3. parse and extract metadata from changed files. * * this is done in parallel over worker processes to improve performance. * * the worst case is to parse all files. * * the best case is no file system access and retrieving all data from * the cache. * * the average case is a small number of changed files. * * 4. serialize the new `HasteMap` in a cache file. * Worker processes can directly access the cache through `HasteMap.read()`. * */ declare class HasteMap extends EventEmitter { private _buildPromise; private _cachePath; private _changeInterval?; private _console; private _options; private _watchers; private _whitelist; private _worker; constructor(options: Options); static getCacheFilePath(tmpdir: Config.Path, name: string, ...extra: Array): string; getCacheFilePath(): string; build(): Promise; /** * 1. read data from the cache or create an empty structure. */ read(): InternalHasteMap; readModuleMap(): HasteModuleMap; /** * 2. crawl the file system. */ private _buildFileMap; /** * 3. parse and extract metadata from changed files. */ private _processFile; private _buildHasteMap; private _cleanup; /** * 4. serialize the new `HasteMap` in a cache file. */ private _persist; /** * Creates workers or parses files and extracts metadata in-process. */ private _getWorker; private _crawl; /** * Watch mode */ private _watch; /** * This function should be called when the file under `filePath` is removed * or changed. When that happens, we want to figure out if that file was * part of a group of files that had the same ID. If it was, we want to * remove it from the group. Furthermore, if there is only one file * remaining in the group, then we want to restore that single file as the * correct resolution for its ID, and cleanup the duplicates index. */ private _recoverDuplicates; end(): Promise; /** * Helpers */ private _ignore; private _isNodeModulesDir; private _createEmptyMap; static H: HType; static DuplicateError: typeof DuplicateError; static ModuleMap: typeof HasteModuleMap; } declare class DuplicateError extends Error { mockPath1: string; mockPath2: string; constructor(mockPath1: string, mockPath2: string); } export = HasteMap;