CODEWITHSUNDEEP
typescripttestingjestjsts-jest
raf
raf

Reputation: 52

Cant run Jest with Typescript

I'm trying to run Typescript tests that run Typescript code with Jest. I've tried to configure Jest with ts-jest in multiple shapes, but without success.

I obtain:

  node_modules/@polkadot/api/promise/index.js:1
    ({"Object.<anonymous>":function(module,exports,require,__dirname,__filename,jest){import _defineProperty from "@babel/runtime/helpers/esm/defineProperty";

  ^^^^^^

    SyntaxError: Cannot use import statement outside a module

      1 | import log4js from "log4js";
    > 2 | import { ApiPromise } from "@polkadot/api/promise";
        | ^

My jest.config.ts:

/** @type {import('ts-jest/dist/types').InitialOptionsTsJest} */
import type { Config } from "@jest/types";
// Sync object
const config: Config.InitialOptions = {
  roots: ["./"],
  preset: "ts-jest",
  coverageDirectory: "../coverage",
  verbose: true,
  testEnvironment: "node",
  //setupFilesAfterEnv: ["./jest.setup.ts"],
  testMatch: ["**/?(*.)+(test).ts"],
  resetMocks: true,
  clearMocks: true,
  extensionsToTreatAsEsm: [".ts"],
  transformIgnorePatterns: ["node_modules/(?!(@polkadot)/)"],
  //collectCoverage: true
};
export default config;

I run the tests with: "jest --config src/test/jest.config.ts --detectOpenHandles"

Any ideas on how to solve this?

I've also tried to execute my code with TAP, but also unsuccessfully. I would appreciate guidance to solve either of the problems, provided that the async tests can run.

Upvotes: 1

Views: 1991

Answers (2)

Offpics
Offpics

Reputation: 293

Did you setup jest with Babel? Jest doesn't understand Typescript so it relies on babel for transpiling.

Upvotes: 1

TheWirv
TheWirv

Reputation: 31

This problem first and foremost has to do with the fact that all code in node_modules will not be transformed before Jest executes, and Jest can only process CommonJS code. You have to add transformIgnorePatterns in order to transform ESM code inside your node_modules to CJS. Have a look at this example for how you actually set it up correctly.

Upvotes: 0

Related Questions