typescript-eslint
Version:
Tooling which enables you to use TypeScript with ESLint
131 lines (130 loc) • 6.27 kB
JavaScript
;
Object.defineProperty(exports, "__esModule", { value: true });
exports.config = config;
/**
* Utility function to make it easy to strictly type your "Flat" config file
* @example
* ```js
* // @ts-check
*
* import eslint from '@eslint/js';
* import tseslint from 'typescript-eslint';
*
* export default tseslint.config(
* eslint.configs.recommended,
* tseslint.configs.recommended,
* {
* rules: {
* '@typescript-eslint/array-type': 'error',
* },
* },
* );
* ```
*
* @deprecated ESLint core now provides this functionality via `defineConfig()`,
* which we now recommend instead. See {@link https://typescript-eslint.io/packages/typescript-eslint/#config-deprecated}.
*/
function config(...configs) {
return configImpl(...configs);
}
// Implementation of the config function without assuming the runtime type of
// the input.
function configImpl(...configs) {
const flattened = configs.flat(Infinity);
return flattened.flatMap((configWithExtends, configIndex) => {
if (configWithExtends == null ||
typeof configWithExtends !== 'object' ||
!('extends' in configWithExtends)) {
// Unless the object is a config object with extends key, just forward it
// along to eslint.
return configWithExtends;
}
const { extends: extendsArr, ..._config } = configWithExtends;
const config = _config;
if (extendsArr == null) {
// If the extends value is nullish, just forward along the rest of the
// config object to eslint.
return config;
}
const name = (() => {
if ('name' in configWithExtends && configWithExtends.name != null) {
if (typeof configWithExtends.name !== 'string') {
throw new Error(`tseslint.config(): Config at index ${configIndex} has a 'name' property that is not a string.`);
}
return configWithExtends.name;
}
return undefined;
})();
const nameErrorPhrase = name != null ? `, named "${name}",` : ' (anonymous)';
if (!Array.isArray(extendsArr)) {
throw new TypeError(`tseslint.config(): Config at index ${configIndex}${nameErrorPhrase} has an 'extends' property that is not an array.`);
}
const extendsArrFlattened = extendsArr.flat(Infinity);
const nonObjectExtensions = [];
for (const [extensionIndex, extension] of extendsArrFlattened.entries()) {
// special error message to be clear we don't support eslint's stringly typed extends.
// https://eslint.org/docs/latest/use/configure/configuration-files#extending-configurations
if (typeof extension === 'string') {
throw new Error(`tseslint.config(): Config at index ${configIndex}${nameErrorPhrase} has an 'extends' array that contains a string (${JSON.stringify(extension)}) at index ${extensionIndex}.` +
" This is a feature of eslint's `defineConfig()` helper and is not supported by typescript-eslint." +
' Please provide a config object instead.');
}
if (extension == null || typeof extension !== 'object') {
nonObjectExtensions.push(extensionIndex);
continue;
}
// https://github.com/eslint/rewrite/blob/82d07fd0e8e06780b552a41f8bcbe2a4f8741d42/packages/config-helpers/src/define-config.js#L448-L450
if ('basePath' in extension) {
throw new TypeError(`tseslint.config(): Config at index ${configIndex}${nameErrorPhrase} has an 'extends' array that contains a config with a 'basePath' property at index ${extensionIndex}.` +
` 'basePath' in 'extends' is not allowed.`);
}
if ('extends' in extension) {
throw new TypeError(`tseslint.config(): Config at index ${configIndex}${nameErrorPhrase} has an 'extends' array that contains a config with an 'extends' property at index ${extensionIndex}.` +
` Nested 'extends' is not allowed.`);
}
}
if (nonObjectExtensions.length > 0) {
const extensionIndices = nonObjectExtensions.join(', ');
throw new TypeError(`tseslint.config(): Config at index ${configIndex}${nameErrorPhrase} contains non-object` +
` extensions at the following indices: ${extensionIndices}.`);
}
const configArray = [];
for (const _extension of extendsArrFlattened) {
const extension = _extension;
const resolvedConfigName = [name, extension.name]
.filter(Boolean)
.join('__');
if (isPossiblyGlobalIgnores(extension)) {
// If it's a global ignores, then just pass it along
configArray.push({
...extension,
...(resolvedConfigName !== '' ? { name: resolvedConfigName } : {}),
});
}
else {
configArray.push({
...extension,
...(config.files ? { files: config.files } : {}),
...(config.ignores ? { ignores: config.ignores } : {}),
...(config.basePath ? { basePath: config.basePath } : {}),
...(resolvedConfigName !== '' ? { name: resolvedConfigName } : {}),
});
}
}
// If the base config could form a global ignores object, then we mustn't include
// it in the output. Otherwise, we must add it in order for it to have effect.
if (!isPossiblyGlobalIgnores(config)) {
configArray.push(config);
}
return configArray;
});
}
/**
* This utility function returns false if the config objects contains any field
* that would prevent it from being considered a global ignores object and true
* otherwise. Note in particular that the `ignores` field may not be present and
* the return value can still be true.
*/
function isPossiblyGlobalIgnores(config) {
return Object.keys(config).every(key => ['name', 'ignores', 'basePath'].includes(key));
}