jest-validate

Generic configuration validation tool that helps you with warnings, errors and deprecation messages as well as showing users examples of correct configuration.

bash npm install --save jest-validate

Usage

```js import {validate} from 'jest-validate';

validate((config: Object), (options: ValidationOptions)); // => {hasDeprecationWarnings: boolean, isValid: boolean} ```

Where ValidationOptions are:

```js type ValidationOptions = { blacklist?: Array, comment?: string, condition?: (option: any, validOption: any) => boolean, deprecate?: ( config: Object, option: string, deprecatedOptions: Object, options: ValidationOptions, ) => true, deprecatedConfig?: {[key: string]: Function}, error?: ( option: string, received: any, defaultValue: any, options: ValidationOptions, ) => void, exampleConfig: Object, recursive?: boolean, title?: Title, unknown?: ( config: Object, exampleConfig: Object, option: string, options: ValidationOptions, ) => void, };

type Title = {| deprecation?: string, error?: string, warning?: string, |}; ```

exampleConfig is the only option required.

API

By default jest-validate will print generic warning and error messages. You can however customize this behavior by providing options: ValidationOptions object as a second argument:

Almost anything can be overwritten to suite your needs.

Options

• recursiveBlacklist – optional array of string keyPaths that should be excluded from deep (recursive) validation.
• comment – optional string to be rendered below error/warning message.
• condition – an optional function with validation condition.
• deprecate, error, unknown – optional functions responsible for displaying warning and error messages.
• deprecatedConfig – optional object with deprecated config keys.
• exampleConfig – the only required option with configuration against which you'd like to test.
• recursive - optional boolean determining whether recursively compare exampleConfig to config (default: true).
• title – optional object of titles for errors and messages.

You will find examples of condition, deprecate, error, unknown, and deprecatedConfig inside source of this repository, named respectively.

Examples

Minimal example:

js validate(config, {exampleConfig});

Example with slight modifications:

js validate(config, { comment: ' Documentation: http://custom-docs.com', deprecatedConfig, exampleConfig, title: { deprecation: 'Custom Deprecation', // leaving 'error' and 'warning' as default }, });

This will output:

Warning:

```bash ● Validation Warning:

Unknown option transformx with value "/node_modules/babel-jest" was found. This is either a typing error or a user mistake. Fixing it will remove this message.

Documentation: http://custom-docs.com ```

Error:

```bash ● Validation Error:

Option transform must be of type: object but instead received: string

Example: { "transform": { "^.+\.js$": "/preprocessor.js" } }

Documentation: http://custom-docs.com ```

Deprecation

Based on deprecatedConfig object with proper deprecation messages. Note custom title:

```bash Custom Deprecation:

Option scriptPreprocessor was replaced by transform, which support multiple preprocessors.

Jest now treats your current configuration as: { "transform": {".*": "xxx"} }

Please update your configuration.

Documentation: http://custom-docs.com ```