^get-tsconfig

Find and parse `tsconfig.json` files. ### Features - Zero dependency (not even TypeScript) - Tested against TypeScript for correctness - Supports comments & dangling commas in `tsconfig.json` - Resolves [`extends`](https://www.typescriptlang.org/tsconfig/#extends) - Fully typed `tsconfig.json` - Validates and throws parsing errors - Tiny! `7 kB` Minified + Gzipped

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## Install ```bash npm install get-tsconfig ``` ## Why? For TypeScript related tooling to correctly parse `tsconfig.json` file without depending on TypeScript. ## API ### getTsconfig(searchPath?, configName?, cache?) Searches for a tsconfig file (defaults to `tsconfig.json`) in the `searchPath` and parses it. (If you already know the tsconfig path, use [`parseTsconfig`](#parsetsconfigtsconfigpath-cache) instead). Returns `null` if a config file cannot be found, or an object containing the path and parsed TSConfig object if found. Returns: ```ts type TsconfigResult = { /** * The path to the tsconfig.json file */ path: string /** * The resolved tsconfig.json file */ config: TsConfigJsonResolved } ``` #### searchPath Type: `string` Default: `process.cwd()` Accepts a path to a file or directory to search up for a `tsconfig.json` file. #### configName Type: `string` Default: `tsconfig.json` The file name of the TypeScript config file. #### cache Type: `Map` Default: `new Map()` Optional cache for fs operations. #### Example ```ts import { getTsconfig } from 'get-tsconfig' // Searches for tsconfig.json starting in the current directory console.log(getTsconfig()) // Find tsconfig.json from a TypeScript file path console.log(getTsconfig('./path/to/index.ts')) // Find tsconfig.json from a directory file path console.log(getTsconfig('./path/to/directory')) // Explicitly pass in tsconfig.json path console.log(getTsconfig('./path/to/tsconfig.json')) // Search for jsconfig.json - https://code.visualstudio.com/docs/languages/jsconfig console.log(getTsconfig('.', 'jsconfig.json')) ``` --- ### parseTsconfig(tsconfigPath, cache?) Parse the tsconfig file provided. Used internally by `getTsconfig`. Returns the parsed tsconfig as `TsConfigJsonResolved`. #### tsconfigPath Type: `string` Required path to the tsconfig file. #### cache Type: `Map` Default: `new Map()` Optional cache for fs operations. #### Example ```ts import { parseTsconfig } from 'get-tsconfig' // Must pass in a path to an existing tsconfig.json file console.log(parseTsconfig('./path/to/tsconfig.custom.json')) ``` --- ### createFileMatcher(tsconfig: TsconfigResult, caseSensitivePaths?: boolean) Given a `tsconfig.json` file, it returns a file-matcher function that determines whether it should apply to a file path. ```ts type FileMatcher = (filePath: string) => TsconfigResult['config'] | undefined ``` #### tsconfig Type: `TsconfigResult` Pass in the return value from `getTsconfig`, or a `TsconfigResult` object. #### caseSensitivePaths Type: `boolean` By default, it uses [`is-fs-case-sensitive`](https://github.com/privatenumber/is-fs-case-sensitive) to detect whether the file-system is case-sensitive. Pass in `true` to make it case-sensitive. #### Example For example, if it's called with a `tsconfig.json` file that has `include`/`exclude`/`files` defined, the file-matcher will return the config for files that match `include`/`files`, and return `undefined` for files that don't match or match `exclude`. ```ts const tsconfig = getTsconfig() const fileMatcher = tsconfig && createFileMatcher(tsconfig) /* * Returns tsconfig.json if it matches the file, * undefined if not */ const configForFile = fileMatcher?.('/path/to/file.ts') const distCode = compileTypescript({ code: sourceCode, tsconfig: configForFile }) ``` --- ### createPathsMatcher(tsconfig: TsconfigResult) Given a tsconfig with [`compilerOptions.paths`](https://www.typescriptlang.org/tsconfig#paths) defined, it returns a matcher function. The matcher function accepts an [import specifier (the path to resolve)](https://nodejs.org/api/esm.html#terminology), checks it against `compilerOptions.paths`, and returns an array of possible paths to check: ```ts function pathsMatcher(specifier: string): string[] ``` This function only returns possible paths and doesn't actually do any resolution. This helps increase compatibility wtih file/build systems which usually have their own resolvers. #### Example ```ts import { getTsconfig, createPathsMatcher } from 'get-tsconfig' const tsconfig = getTsconfig() const pathsMatcher = createPathsMatcher(tsconfig) const exampleResolver = (request: string) => { if (pathsMatcher) { const tryPaths = pathsMatcher(request) // Check if paths in `tryPaths` exist } } ``` ## FAQ ### How can I use TypeScript to parse `tsconfig.json`? This package is a re-implementation of TypeScript's `tsconfig.json` parser. However, if you already have TypeScript as a dependency, you can simply use it's API: ```ts import { sys as tsSys, findConfigFile, readConfigFile, parseJsonConfigFileContent } from 'typescript' // Find tsconfig.json file const tsconfigPath = findConfigFile(process.cwd(), tsSys.fileExists, 'tsconfig.json') // Read tsconfig.json file const tsconfigFile = readConfigFile(tsconfigPath, tsSys.readFile) // Resolve extends const parsedTsconfig = parseJsonConfigFileContent( tsconfigFile.config, tsSys, path.dirname(tsconfigPath) ) ``` ## Sponsors