ts-jest

https://kulshekhar.github.io/ts-jest/docs
Admin
A Jest transformer with source map support that lets you use Jest to test projects written in...
Tokens:26,042
Snippets:202
Trust Score:8.3
Update:6 hours ago
Show doc for...
Tokens:
Raw
### createJsWithBabelLegacyPreset usage example (jest.config.ts)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Example configuration file that imports createJsWithBabelLegacyPreset and JestConfigWithTsJest from 'ts-jest', creates a legacy preset config with optional options, spreads it into a Jest config object, and exports it as default. Use this for a legacy setup that uses babel-jest for additional transformation.

```ts
import { createJsWithBabelLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### Install ts-jest with Bun

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/installation

Installs ts-jest and its dependencies (jest, typescript, @types/jest) as dev dependencies using Bun.

```bash
bun add --dev jest typescript ts-jest @types/jest
```

--------------------------------

### Global setup/teardown with tsconfig-paths

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/paths-mapping

Imports 'tsconfig-paths/register' in global setup and teardown files to enable path mapping, since Jest does not process these files with moduleNameMapper.

```ts
import 'tsconfig-paths/register'

/**
 * Your global setup
 */

// ./path/to/globalTeardown.ts
import 'tsconfig-paths/register'

/**
 * Your global teardown
 */
```

--------------------------------

### createJsWithBabelPreset usage example (jest.config.ts)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Example configuration file that imports createJsWithBabelPreset and JestConfigWithTsJest from 'ts-jest', creates a preset config with optional options, spreads it into a Jest config object, and exports it as default. Use this to set up Jest with babel-jest for additional transformation of JavaScript/TypeScript files.

```ts
import { createJsWithBabelPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### createJsWithBabelEsmPreset usage example (jest.config.ts)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Example configuration file that imports createJsWithBabelEsmPreset and JestConfigWithTsJest from 'ts-jest', creates an ESM preset config with optional options, spreads it into a Jest config object, and exports it as default. Use this for ESM projects that need babel-jest for additional transformation.

```ts
import { createJsWithBabelEsmPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelEsmPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### Install ts-jest with pnpm

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/installation

Installs ts-jest and its dependencies (jest, typescript, @types/jest) as dev dependencies using pnpm.

```bash
pnpm add --save-dev jest typescript ts-jest @types/jest
```

--------------------------------

### Install ts-jest with npm

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/installation

Installs ts-jest and its dependencies (jest, typescript, @types/jest) as dev dependencies using npm.

```bash
npm install --save-dev jest typescript ts-jest @types/jest
```

--------------------------------

### TypeScript legacy import/export example

Source: https://kulshekhar.github.io/ts-jest/docs/babel7-or-ts

Demonstrates legacy import/export syntax that is not supported by @babel/preset-typescript.

```ts
import lib = require('lib')
// ...
export = myVar
```

--------------------------------

### createDefaultLegacyPreset usage example

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Shows how to create a Jest configuration using createDefaultLegacyPreset in a jest.config.ts file. Note the example uses createDefaultPreset instead of createDefaultLegacyPreset in the call, which appears to be a typo in the source.

```ts
import { createDefaultLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createDefaultPreset({
  //...optionsa
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### tsconfig.json with baseUrl and paths

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/paths-mapping

Defines path aliases @App/* and lib/* in TypeScript compiler options. Required for ts-jest path mapping setup.

```json
{
  "compilerOptions": {
    "baseUrl": ".",
    "paths": {
      "@App/*": ["src/*"],
      "lib/*": ["common/*"]
    }
  }
}
```

--------------------------------

### Install ts-jest with Yarn

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/installation

Installs ts-jest and its dependencies (jest, typescript, @types/jest) as dev dependencies using Yarn.

```bash
yarn add --dev jest typescript ts-jest @types/jest
```

--------------------------------

### Install ts-node as dev dependency (Bun)

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Required when using Jest config in TypeScript. Install ts-node as a dev dependency.

```bash
bun add --dev ts-node
```

--------------------------------

### Install ts-node as dev dependency (pnpm)

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Required when using Jest config in TypeScript. Install ts-node as a dev dependency.

```bash
pnpm add -D ts-node
```

--------------------------------

### Run Jest with --experimental-vm-modules flag

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Execute Jest with the --experimental-vm-modules flag for Node.js to enable ESM support.

```bash
node --experimental-vm-modules node_modules/jest/bin/jest.js
```

--------------------------------

### TypeScript namespace example

Source: https://kulshekhar.github.io/ts-jest/docs/babel7-or-ts

Illustrates a TypeScript namespace, which is not supported by @babel/preset-typescript.

```ts
namespace app {
  export const VERSION = '1.0.0'
  export class App {
    /* ... */
  }
}
```

--------------------------------

### SyntaxError example for untransformed module

Source: https://kulshekhar.github.io/ts-jest/docs/guides/troubleshooting

Example error output showing a module that needs to be transformed because it uses import statements outside a module.

```Shell
    SyntaxError: Cannot use import statement outside a module
    > 22 | import Component from "../../node_modules/some-module/lib";
         | ^
```

--------------------------------

### Install ts-node as dev dependency (npm)

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Required when using Jest config in TypeScript. Install ts-node as a dev dependency.

```bash
npm install -D ts-node
```

--------------------------------

### Install ts-node as dev dependency (Yarn)

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Required when using Jest config in TypeScript. Install ts-node as a dev dependency.

```bash
yarn add --dev ts-node
```

--------------------------------

### createDefaultPreset usage example

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Shows how to create a Jest configuration using createDefaultPreset in a jest.config.ts file. The presetConfig is spread into the final Jest config object.

```ts
import { createDefaultPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createDefaultPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### createJsWithTsEsmPreset usage example (jest.config.ts)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Shows how to create an ESM Jest configuration for JavaScript/TypeScript files using createJsWithTsEsmPreset. The presetConfig is spread into a JestConfigWithTsJest object and exported as default.

```ts
import { createJsWithTsEsmPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsEsmPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### createJsWithTsLegacyPreset usage example (jest.config.ts)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Shows how to create a legacy Jest configuration for JavaScript/TypeScript files using createJsWithTsLegacyPreset. The presetConfig is spread into a JestConfigWithTsJest object and exported as default.

```ts
import { createJsWithTsLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### Jest config without helper (moduleNameMapper)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/paths-mapping

Manual Jest moduleNameMapper configuration for path aliases. Requires explicit mapping for each alias.

```ts
import type { Config } from 'jest'

const jestConfig: Config = {
  // [...]
  moduleNameMapper: {
    '^@App/(.*)$': '<rootDir>/src/$1',
    '^lib/(.*)$': '<rootDir>/common/$1',
  },
}

export default jestConfig
```

--------------------------------

### Example: jest.config.ts using createJsWithBabelEsmLegacyPreset

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Shows how to create a legacy ESM Jest configuration with createJsWithBabelEsmLegacyPreset in a jest.config.ts file. The presetConfig is spread into a JestConfigWithTsJest object and exported as default. The options object is left with a placeholder comment for user-provided configuration.

```TypeScript
import { createJsWithBabelEsmLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelEsmLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### createJsWithTsPreset usage in jest.config.ts

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Example configuration using createJsWithTsPreset to build a Jest config that processes JavaScript and TypeScript files.

```TypeScript
import { createJsWithTsPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### Create Jest config with npx ts-jest config:init

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/installation

Automatically creates a basic Jest configuration file that tells Jest to use the ts-jest preset for transpiling TypeScript files. If npx is not found, replace 'npx XXX' with 'node node_modules/.bin/XXX'.

```npm
npx ts-jest config:init
```

--------------------------------

### Alternative Yarn command for ESM

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Alternative way for Yarn users to run Jest with ESM support. Also works with Yarn Plug'n'Play.

```bash
yarn node --experimental-vm-modules $(yarn bin jest)
```

--------------------------------

### TypeScript caret type-casting with JSX example

Source: https://kulshekhar.github.io/ts-jest/docs/babel7-or-ts

Shows caret type-casting syntax that is not supported when JSX is enabled.

```ts
const val = <string>input
```

--------------------------------

### createJsWithTsEsmLegacyPreset usage example (jest.config.ts)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Shows how to create a legacy ESM Jest configuration for JavaScript/TypeScript files using createJsWithTsEsmLegacyPreset. The presetConfig is spread into a JestConfigWithTsJest object and exported as default.

```ts
import { createJsWithTsEsmLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsEsmLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### Create Jest config with yarn ts-jest config:init

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/installation

Automatically creates a basic Jest configuration file that tells Jest to use the ts-jest preset for transpiling TypeScript files.

```yarn
yarn ts-jest config:init
```

--------------------------------

### createDefaultLegacyEsmPreset usage in jest.config.ts

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Example configuration using createDefaultLegacyEsmPreset to build a Jest config with legacy ESM support for TypeScript files.

```TypeScript
import { createDefaultLegacyEsmPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createDefaultLegacyEsmPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```

--------------------------------

### TypeScript const enum example

Source: https://kulshekhar.github.io/ts-jest/docs/babel7-or-ts

Shows a const enum, which is not supported by @babel/preset-typescript.

```ts
const enum Directions {
  Up,
  Down,
  Left,
  Right,
}
```

--------------------------------

### Jest config using ESM presets

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Use createDefaultEsmPreset from ts-jest to configure Jest for ESM. This preset handles ESM-specific settings.

```ts
import type { Config } from 'jest'
import { createDefaultEsmPreset } from 'ts-jest'

const presetConfig = createDefaultEsmPreset({
  //...options
})

export default {
  ...presetConfig,
} satisfies Config
```

--------------------------------

### Jest config with custom resolver

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Add the custom resolver to Jest config to resolve .mjs/.mts extensions.

```ts
import type { Config } from 'jest'

const config: Config = {
  //...other options
  resolver: '<rootDir>/path/to/custom-resolver.ts',
}
```

--------------------------------

### Jest config without ESM presets

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Manually configure extensionsToTreatAsEsm and transform with useESM: true when not using ESM presets.

```ts
import type { Config } from 'jest'
import { TS_EXT_TO_TREAT_AS_ESM, ESM_TS_TRANSFORM_PATTERN } from 'ts-jest'

export default {
  extensionsToTreatAsEsm: [...TS_EXT_TO_TREAT_AS_ESM],
  transform: {
    [ESM_TS_TRANSFORM_PATTERN]: [
      'ts-jest',
      {
        //...other `ts-jest` options
        useESM: true,
      },
    ],
  },
} satisfies Config
```

--------------------------------

### Jest config with pathsToModuleNameMapper helper

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/paths-mapping

Uses ts-jest's pathsToModuleNameMapper to auto-generate moduleNameMapper from tsconfig paths. Requires importing compilerOptions from tsconfig and setting modulePaths to baseUrl. Optional prefix and useESM options.

```ts
import { pathsToModuleNameMapper } from 'ts-jest'
// In the following statement, replace `./tsconfig` with the path to your `tsconfig` file
// which contains the path mapping (ie the `compilerOptions.paths` option):
import { compilerOptions } from './tsconfig'
import type { Config } from 'jest'

const jestConfig: Config = {
  // [...]
  roots: ['<rootDir>'],
  modulePaths: [compilerOptions.baseUrl], // <-- This will be set to 'baseUrl' value
  moduleNameMapper: pathsToModuleNameMapper(compilerOptions.paths /*, { prefix: '<rootDir>/' } */),
}

export default jestConfig
```

--------------------------------

### TypeScript type error example

Source: https://kulshekhar.github.io/ts-jest/docs/babel7-or-ts

Shows a TypeScript type error that Babel's @babel/preset-typescript would not catch because it transpiles files as isolated modules without type-checking.

```ts
const str: string = 42
```

--------------------------------

### tsconfig.spec.json with ES module values

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Recommended to use ES2022 or ESNext for full support of recent ESM features. Must be used with type: "module" in package.json.

```json
{
  "compilerOptions": {
    "module": "ES2022", // or `ESNext`
    "target": "ESNext",
    "esModuleInterop": true
  }
}
```

--------------------------------

### Set moduleNameMapper in Jest config

Source: https://kulshekhar.github.io/ts-jest/docs/guides/troubleshooting

Add `moduleNameMapper` to your Jest configuration to map import paths to real physical paths.

```TypeScript
import type { Config } from 'jest'

const config: Config = {
  //...
  moduleNameMapper: {
    '<import-path>': '<rootDir>/<real-physical-path>',
  },
}

export default config
```

--------------------------------

### createJsWithTsPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a configuration to process JavaScript/TypeScript files (.js/.jsx/.ts/.tsx). Returns an object containing Jest's transform property.

```APIDOC
## createJsWithTsPreset(options)

### Description
Creates a configuration to process JavaScript/TypeScript files (.js/.jsx/.ts/.tsx). Returns an object containing Jest's transform property.

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` - Optional - See tsconfig options page
  - `isolatedModules` - Optional - See isolatedModules options page
  - `compiler` - Optional - See compiler options page
  - `astTransformers` - Optional - See astTransformers options page
  - `diagnostics` - Optional - See diagnostics options page
  - `stringifyContentPathRegex` - Optional - See stringifyContentPathRegex options page

### Returns
An object containing Jest's `transform` property:

```ts
import type { TsConfigJson } from 'type-fest'

interface TsJestTransformerOptions {
  tsconfig?: boolean | string | TsConfigJson.CompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithTsPreset = {
  transform: {
    '^.+\\.[tj]sx?$': ['ts-jest', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createJsWithTsPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### createJsWithBabelPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a Jest configuration preset for processing JavaScript/TypeScript files using babel-jest for additional transformation. Accepts optional configuration options and returns an object containing Jest's transform property.

```APIDOC
## createJsWithBabelPreset(options)

### Description
Creates a configuration to process JavaScript/TypeScript files (`.js`/`.jsx`/`.ts`/`.tsx`) which uses `babel-jest` to perform additional transformation.

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` (boolean | string | TsConfigJson.CompilerOptions) - Optional - See tsconfig options page.
  - `isolatedModules` (boolean) - Optional - See isolatedModules options page.
  - `compiler` (string) - Optional - See compiler options page.
  - `astTransformers` (ConfigCustomTransformer) - Optional - See astTransformers options page.
  - `diagnostics` (boolean | object) - Optional - See diagnostics options page. Object properties: `pretty` (boolean), `ignoreCodes` (number | string | Array<number|string>), `exclude` (string[]), `warnOnly` (boolean).
  - `babelConfig` (boolean | string | BabelConfig) - Optional - See babelConfig options page.
  - `stringifyContentPathRegex` (string | RegExp) - Optional - See stringifyContentPathRegex options page.

### Returns
An object containing Jest's `transform` property:
```ts
import type { TsConfigJson } from 'type-fest'

interface TsJestTransformerOptions {
  tsconfig?: boolean | string | TsConfigJson.CompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  babelConfig?: boolean | string | BabelConfig
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithBabelPreset = {
  transform: {
    '^.+\\.[tj]sx?$': ['ts-jest', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createJsWithBabelPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### Disable allowJs in tsconfig

Source: https://kulshekhar.github.io/ts-jest/docs/guides/troubleshooting

Set `compilerOptions.allowJs` to `false` in your tsconfig to prevent ts-jest from processing JavaScript files, which can cause performance issues.

```JSON
{
  "compilerOptions": {
    "allowJs": false
  }
}
```

--------------------------------

### Set transformIgnorePatterns in Jest config

Source: https://kulshekhar.github.io/ts-jest/docs/guides/troubleshooting

Add `transformIgnorePatterns` to your Jest configuration to specify which node modules should be transformed during the Jest execution step.

```TypeScript
import type { Config } from 'jest'

const config: Config = {
  //...
  transformIgnorePatterns: ['node_modules/(?!(some-module|another-module))'],
}

export default config
```

--------------------------------

### createJsWithBabelLegacyPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a LEGACY configuration to process JavaScript/TypeScript files using babel-jest for additional transformation. Accepts optional configuration options and returns an object containing Jest's transform property.

```APIDOC
## createJsWithBabelLegacyPreset(options)

### Description
Creates a **LEGACY** configuration to process JavaScript/TypeScript files (`.js`/`.jsx`/`.ts`/`.tsx`) which uses `babel-jest` to perform additional transformation.

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` (boolean | string | RawCompilerOptions) - Optional - See tsconfig options page.
  - `isolatedModules` (boolean) - Optional - See isolatedModules options page.
  - `compiler` (string) - Optional - See compiler options page.
  - `astTransformers` (ConfigCustomTransformer) - Optional - See astTransformers options page.
  - `diagnostics` (boolean | object) - Optional - See diagnostics options page. Object properties: `pretty` (boolean), `ignoreCodes` (number | string | Array<number|string>), `exclude` (string[]), `warnOnly` (boolean).
  - `babelConfig` (boolean | string | BabelConfig) - Optional - See babelConfig options page.
  - `stringifyContentPathRegex` (string | RegExp) - Optional - See stringifyContentPathRegex options page.

### Returns
An object containing Jest's `transform` property:
```ts
interface TsJestTransformerOptions {
  tsconfig?: boolean | string | RawCompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  babelConfig?: boolean | string | BabelConfig
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithBabelPreset = {
  transform: {
    '^.+\\.[tj]sx?$': ['ts-jest/legacy', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createJsWithBabelLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### createJsWithBabelEsmPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates an ESM configuration to process JavaScript/TypeScript files using babel-jest for additional transformation. Accepts optional configuration options and returns an object containing Jest's transform property.

```APIDOC
## createJsWithBabelEsmPreset(options)

### Description
Creates a ESM configuration to process JavaScript/TypeScript files (`.js`/`.mjs`/`.jsx`/`.mjsx`/`.ts`/`.mts`/`.tsx`/`.mtsx`) which uses `babel-jest` to perform additional transformation.

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` (boolean | string | TsConfigJson.CompilerOptions) - Optional - See tsconfig options page.
  - `isolatedModules` (boolean) - Optional - See isolatedModules options page.
  - `compiler` (string) - Optional - See compiler options page.
  - `astTransformers` (ConfigCustomTransformer) - Optional - See astTransformers options page.
  - `diagnostics` (boolean | object) - Optional - See diagnostics options page. Object properties: `pretty` (boolean), `ignoreCodes` (number | string | Array<number|string>), `exclude` (string[]), `warnOnly` (boolean).
  - `babelConfig` (boolean | string | BabelConfig) - Optional - See babelConfig options page.
  - `stringifyContentPathRegex` (string | RegExp) - Optional - See stringifyContentPathRegex options page.

### Returns
An object containing Jest's `transform` property:
```ts
import type { TsConfigJson } from 'type-fest'

interface TsJestTransformerOptions {
  tsconfig?: boolean | string | TsConfigJson.CompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  babelConfig?: boolean | string | BabelConfig
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithBabelPreset = {
  transform: {
    '^.+\\.[tj]sx?$': ['ts-jest', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createJsWithBabelEsmPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelEsmPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### Set roots in Jest config

Source: https://kulshekhar.github.io/ts-jest/docs/guides/troubleshooting

Add `roots` to your Jest configuration to fix 'Cannot find module' errors when `rootDir` is not referenced correctly.

```TypeScript
import type { Config } from 'jest'

const config: Config = {
  //...
  roots: ['<rootDir>'],
}

export default config
```

--------------------------------

### Set moduleDirectories and modulePaths in Jest config

Source: https://kulshekhar.github.io/ts-jest/docs/guides/troubleshooting

Add `moduleDirectories` and `modulePaths` to your Jest configuration to include module directories and paths for module resolution.

```TypeScript
import type { Config } from 'jest'

const config: Config = {
  //...
  moduleDirectories: ['node_modules', '<module-directory>'],
  modulePaths: ['<path-of-module>'],
}

export default config
```

--------------------------------

### createDefaultEsmPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates an ESM configuration to process TypeScript files (.ts/.mts/.tsx/.mtsx). Returns an object containing Jest's transform property.

```APIDOC
## createDefaultEsmPreset(options)

### Description
Creates an ESM configuration to process TypeScript files (.ts/.mts/.tsx/.mtsx). Returns an object containing Jest's transform property.

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` - Optional - See tsconfig options page
  - `isolatedModules` - Optional - See isolatedModules options page
  - `compiler` - Optional - See compiler options page
  - `astTransformers` - Optional - See astTransformers options page
  - `diagnostics` - Optional - See diagnostics options page
  - `stringifyContentPathRegex` - Optional - See stringifyContentPathRegex options page

### Returns
An object containing Jest's `transform` property:

```ts
interface TsJestTransformerOptions {
  tsconfig?: boolean | string | RawCompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type DefaultEsmPreset = {
  extensionsToTreatAsEsm: string[]
  transform: {
    '^.+\\.m?tsx?$': ['ts-jest', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createDefaultEsmPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createDefaultEsmPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### createDefaultLegacyEsmPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a LEGACY ESM configuration to process TypeScript files (.ts/.mts/.tsx/.mtsx). Returns an object containing Jest's transform property.

```APIDOC
## createDefaultLegacyEsmPreset(options)

### Description
Creates a LEGACY ESM configuration to process TypeScript files (.ts/.mts/.tsx/.mtsx). Returns an object containing Jest's transform property.

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` - Optional - See tsconfig options page
  - `isolatedModules` - Optional - See isolatedModules options page
  - `compiler` - Optional - See compiler options page
  - `astTransformers` - Optional - See astTransformers options page
  - `diagnostics` - Optional - See diagnostics options page
  - `stringifyContentPathRegex` - Optional - See stringifyContentPathRegex options page

### Returns
An object containing Jest's `transform` property:

```ts
import type { TsConfigJson } from 'type-fest'

interface TsJestTransformerOptions {
  tsconfig?: boolean | string | TsConfigJson.CompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type DefaultEsmPreset = {
  extensionsToTreatAsEsm: string[]
  transform: {
    '^.+\\.m?tsx?$': ['ts-jest/legacy', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createDefaultLegacyEsmPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createDefaultLegacyEsmPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### createJsWithTsEsmPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates an ESM configuration preset for processing JavaScript and TypeScript files. It returns an object containing Jest's transform property.

```APIDOC
## createJsWithTsEsmPreset(options)

### Description
Create a ESM configuration to process JavaScript/TypeScript files (`.js`/`.mjs`/`.jsx`/`.mjsx`/`.ts`/`.mts`/`.tsx`/`.mtsx`).

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` (boolean | string | TsConfigJson.CompilerOptions) - Optional - See tsconfig options page.
  - `isolatedModules` (boolean) - Optional - See isolatedModules options page.
  - `compiler` (string) - Optional - See compiler options page.
  - `astTransformers` (ConfigCustomTransformer) - Optional - See astTransformers options page.
  - `diagnostics` (boolean | object) - Optional - See diagnostics options page. Object properties: `pretty` (boolean), `ignoreCodes` (number | string | Array<number|string>), `exclude` (string[]), `warnOnly` (boolean).
  - `stringifyContentPathRegex` (string | RegExp) - Optional - See stringifyContentPathRegex options page.

### Returns
An object containing Jest's `transform` property:
```ts
import type { TsConfigJson } from 'type-fest'

interface TsJestTransformerOptions {
  tsconfig?: boolean | string | TsConfigJson.CompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithTsPreset = {
  transform: {
    '^.+\\.m?[tj]sx?$': ['ts-jest', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createJsWithTsEsmPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsEsmPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### createJsWithTsLegacyPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a legacy Jest configuration preset for processing JavaScript and TypeScript files. It returns an object containing Jest's transform property.

```APIDOC
## createJsWithTsLegacyPreset(options)

### Description
Creates a **LEGACY** configuration to process JavaScript/TypeScript files (`.js`/`.jsx`/`.ts`/`.tsx`).

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` (boolean | string | RawCompilerOptions) - Optional - See tsconfig options page.
  - `isolatedModules` (boolean) - Optional - See isolatedModules options page.
  - `compiler` (string) - Optional - See compiler options page.
  - `astTransformers` (ConfigCustomTransformer) - Optional - See astTransformers options page.
  - `diagnostics` (boolean | object) - Optional - See diagnostics options page. Object properties: `pretty` (boolean), `ignoreCodes` (number | string | Array<number|string>), `exclude` (string[]), `warnOnly` (boolean).
  - `stringifyContentPathRegex` (string | RegExp) - Optional - See stringifyContentPathRegex options page.

### Returns
An object containing Jest's `transform` property:
```ts
interface TsJestTransformerOptions {
  tsconfig?: boolean | string | RawCompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithTsPreset = {
  transform: {
    '^.+\\.[tj]sx?$': ['ts-jest/legacy', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createJsWithTsLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### createJsWithBabelEsmLegacyPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a legacy ESM configuration for processing JavaScript and TypeScript files using babel-jest for additional transformation. Returns an object containing Jest's transform property.

```APIDOC
## createJsWithBabelEsmLegacyPreset(options)

### Description
Creates a **LEGACY** ESM configuration to process JavaScript/TypeScript files (`.js`/`.mjs`/`.jsx`/`.mjsx`/`.ts`/`.mts`/`.tsx`/`.mtsx`) which uses `babel-jest` to perform additional transformation.

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` - see tsconfig options
  - `isolatedModules` - see isolatedModules options
  - `compiler` - see compiler options
  - `astTransformers` - see astTransformers options
  - `diagnostics` - see diagnostics options
  - `babelConfig` - see babelConfig options
  - `stringifyContentPathRegex` - see stringifyContentPathRegex options

### Returns
An object containing Jest's `transform` property:

```ts
interface TsJestTransformerOptions {
  tsconfig?: boolean | string | RawCompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  babelConfig?: boolean | string | BabelConfig
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithBabelPreset = {
  transform: {
    '^.+\\.[tj]sx?$': ['ts-jest/legacy', TsJestTransformerOptions]
  }
}
```

### Example
jest.config.ts

```ts
import { createJsWithBabelEsmLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithBabelEsmLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### Mock named import with jest.mock

Source: https://kulshekhar.github.io/ts-jest/docs/guides/mock-es6-class

For named imports like `import { OAuth2 } from './oauth'`, replace `default` with the imported module name, `OAuth2` in this example.

```TypeScript
jest.mock('./oauth', () => {
    return {
        OAuth2: ... // mock here
    }
})
```

--------------------------------

### Run config:migrate on jest.config.js with npm

Source: https://kulshekhar.github.io/ts-jest/docs/migration

Use this command to migrate a Jest configuration stored in jest.config.js when using npm. It updates the configuration to be compatible with ts-jest versions after 23.10.

```npm
npx ts-jest config:migrate jest.config.js
```

--------------------------------

### Run config:migrate on package.json with npm

Source: https://kulshekhar.github.io/ts-jest/docs/migration

Use this command to migrate a Jest configuration stored in the 'jest' property of package.json when using npm. It updates the configuration to be compatible with ts-jest versions after 23.10.

```npm
npx ts-jest config:migrate package.json
```

--------------------------------

### createDefaultLegacyPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a legacy Jest configuration preset for processing TypeScript files (.ts/.tsx). It returns an object containing Jest's transform property configured with ts-jest/legacy.

```APIDOC
## createDefaultLegacyPreset(options)

### Description
Creates a legacy Jest configuration preset for processing TypeScript files (.ts/.tsx). It returns an object containing Jest's transform property configured with ts-jest/legacy.

### Parameters
- **options** (object) - Optional - Configuration options:
  - `tsconfig` - see tsconfig options
  - `isolatedModules` - see isolatedModules options
  - `compiler` - see compiler options
  - `astTransformers` - see astTransformers options
  - `diagnostics` - see diagnostics options
  - `stringifyContentPathRegex` - see stringifyContentPathRegex options

### Returns
An object containing Jest's `transform` property:

```ts
import type { TsConfigJson } from 'type-fest'

interface TsJestTransformerOptions {
  tsconfig?: boolean | string | TsConfigJson.CompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type DefaultPreset = {
  transform: {
    '^.+\.tsx?$': ['ts-jest/legacy', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createDefaultLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createDefaultPreset({
  //...optionsa
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### createJsWithTsEsmLegacyPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a legacy ESM configuration preset for processing JavaScript and TypeScript files. It returns an object containing Jest's transform property.

```APIDOC
## createJsWithTsEsmLegacyPreset(options)

### Description
Create a **LEGACY** ESM configuration to process JavaScript/TypeScript files (`.js`/`.mjs`/`.jsx`/`.mjsx`/`.ts`/`.mts`/`.tsx`/`.mtsx`).

### Parameters
- `options` (object) - Optional - Configuration options:
  - `tsconfig` (boolean | string | RawCompilerOptions) - Optional - See tsconfig options page.
  - `isolatedModules` (boolean) - Optional - See isolatedModules options page.
  - `compiler` (string) - Optional - See compiler options page.
  - `astTransformers` (ConfigCustomTransformer) - Optional - See astTransformers options page.
  - `diagnostics` (boolean | object) - Optional - See diagnostics options page. Object properties: `pretty` (boolean), `ignoreCodes` (number | string | Array<number|string>), `exclude` (string[]), `warnOnly` (boolean).
  - `stringifyContentPathRegex` (string | RegExp) - Optional - See stringifyContentPathRegex options page.

### Returns
An object containing Jest's `transform` property:
```ts
interface TsJestTransformerOptions {
  tsconfig?: boolean | string | RawCompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type JsWithTsPreset = {
  transform: {
    '^.+\\.m?[tj]sx?$': ['ts-jest/legacy', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createJsWithTsEsmLegacyPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createJsWithTsEsmLegacyPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```

--------------------------------

### tsconfig.spec.json with hybrid module values

Source: https://kulshekhar.github.io/ts-jest/docs/guides/esm-support

Hybrid values (Node16/Node18/NodeNext) require isolatedModules: true. Must be used with type: "module" in package.json.

```json
{
  "compilerOptions": {
    "module": "Node16", // or Node18/NodeNext
    "target": "ESNext",
    "esModuleInterop": true,
    "isolatedModules": true
  }
}
```

--------------------------------

### createDefaultPreset(options)

Source: https://kulshekhar.github.io/ts-jest/docs/getting-started/presets

Creates a Jest configuration preset for processing TypeScript files (.ts/.tsx). It returns an object containing Jest's transform property configured with ts-jest.

```APIDOC
## createDefaultPreset(options)

### Description
Creates a Jest configuration preset for processing TypeScript files (.ts/.tsx). It returns an object containing Jest's transform property configured with ts-jest.

### Parameters
- **options** (object) - Optional - Configuration options:
  - `tsconfig` - see tsconfig options
  - `isolatedModules` - see isolatedModules options
  - `compiler` - see compiler options
  - `astTransformers` - see astTransformers options
  - `diagnostics` - see diagnostics options
  - `stringifyContentPathRegex` - see stringifyContentPathRegex options

### Returns
An object containing Jest's `transform` property:

```ts
import type { TsConfigJson } from 'type-fest'

interface TsJestTransformerOptions {
  tsconfig?: boolean | string | TsConfigJson.CompilerOptions
  isolatedModules?: boolean
  astTransformers?: ConfigCustomTransformer
  diagnostics?:
    | boolean
    | {
        pretty?: boolean
        ignoreCodes?: number | string | Array<number | string>
        exclude?: string[]
        warnOnly?: boolean
      }
  stringifyContentPathRegex?: string | RegExp
}

export type DefaultPreset = {
  transform: {
    '^.+.tsx?$': ['ts-jest', TsJestTransformerOptions]
  }
}
```

### Example
```ts
import { createDefaultPreset, type JestConfigWithTsJest } from 'ts-jest'

const presetConfig = createDefaultPreset({
  //...options
})

const jestConfig: JestConfigWithTsJest = {
  ...presetConfig,
}

export default jestConfig
```
```
Tokens:
Raw