useESM option

The useESM option allows ts-jest to transform codes to ESM syntax if possible.

The default value is false, ts-jest will transform codes to CommonJS syntax.

tip

See more about ESM support in dedicated guide

Examples

jest.config.ts

import type { Config } from 'jest'

const jestConfig: Config = {
  // [...]
  transform: {
    // '^.+\\.[tj]sx?$' to process ts,js,tsx,jsx with `ts-jest`
    // '^.+\\.m?[tj]sx?$' to process ts,js,tsx,jsx,mts,mjs,mtsx,mjsx with `ts-jest`
    '^.+\\.tsx?$': [
      'ts-jest',
      {
        useESM: true,
      },
    ],
  },
}

export default jestConfig