Ts-jest: Import from index.ts export not working

[yelhouti]

Issue :

Import from index.ts export not working, ex:
file structure:
app
|--shared
|--index.ts
|--utils.ts

utils.ts:

export function myFunction(){...

index.ts:

export * from 'utils.ts';

import {myFunction} from 'app/shared' doesn't work in jest (works when running the app).
export {myFunction} from 'app/shared.index' works.

Expected behavior :

ts-jest should work the same was as plain ts

[bscaspar]

I am experiencing this error too. Getting the Jest encountered an unexpected token error pointing to the first line of my index.ts file which is exporting modules like export * from './moduleFile';. I've tried all sorts of fixes with babel plugins and other configurations with no luck. Here's my jest config (in my package.json file):

"jest": {
    "preset": "jest-expo",
    "globals": {
      "NODE_ENV": "test"
    },
    "moduleFileExtensions": [
      "ts",
      "tsx",
      "js",
      "jsx",
      "json"
    ],
    "transform": {
      "^.+\\.jsx?$": "<rootDir>/node_modules/babel-jest",
      "^.+\\.tsx?$": "ts-jest"
    },
    "testRegex": "(/__tests__/.*|(\\.|/)(test|spec))\\.(jsx?|tsx?)$",
    "transformIgnorePatterns": [
      "node_modules/(?!((jest-)?react-native|react-clone-referenced-element|expo(nent)?|@expo(nent)?/.*|react-navigation|@react-navigation/.*|sentry-expo|native-base|react-dom|@unimodules))"
    ]
  },

[ahnpnl]

hi, would you please provide a minimum repo ?

[bscaspar]

I am no longer having this issue. I've gone through a considerable amount of refactoring and changes so I can't pinpoint what fixed it. For anyone running into this here's what my jest.config looks like now:

const { defaults: tsjPreset } = require('ts-jest/presets');

module.exports = {
  preset: 'jest-expo',
  globals: {
    'ts-jest': {
      tsConfig: './tsconfig.jest.json',
    },
  },
  transform: {
    '^.+\\.(js|jsx)?$': '<rootDir>/node_modules/babel-jest',
    ...tsjPreset.transform,
  },
  moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json'],
  testRegex: '(/__tests__/.*|(\\.|/)(test|spec))\\.(jsx?|tsx?)$',
  transformIgnorePatterns: [
    'node_modules/(?!((jest-)?react-native|react-clone-referenced-element|expo(nent)?|@expo(nent)?/.*|react-navigation|@react-navigation/.*|sentry-expo|@sentry|native-base|native-base-shoutem-theme|react-dom|unimodules|@unimodules|expo-asset))',
    'local_modules',
  ],
  testPathIgnorePatterns: ['/node_modules', '/local_modules/'],
  coveragePathIgnorePatterns: [
    '/node_modules',
    '/local_modules/',
    '/src/theme/components/',
    '/src/theme/variables/',
    '/__test-data__/',
  ],
  moduleNameMapper: {
    '\\.(jpg|ico|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$':
      '<rootDir>/__mocks__/fileMock.js',
  },
};

[vicary]

I can confirm that explicitly adding index in the import statement works, tsconfig.json is the one automatically generated by create-react-app.

In my case, the erroneous import statement looks like this import {...} from "./App/"; which works fine in the app but not in jest. It works after changing to import {...} from "./App/index";

[ahnpnl]

@vicary do you still encounter the same issue ? If yes, please us provide a repo :) thanks

[jyeros]

I am having the same issue and using import {...} from "./module/index" doesn't work I need to specify the module when i import it. I create e minimal repo where I can reproduce it repo in master the problem exist but in this branch remove-import-from-index-export works well and the diff is

diff --git a/src/services/api/http.ts b/src/services/api/http.ts
index 80bd1a1..2f422c4 100644
--- a/src/services/api/http.ts
+++ b/src/services/api/http.ts
@@ -2,3 +2,3 @@ import axios, { AxiosRequestConfig, Method } from "axios"

-import { logger } from "../../loaders"
+import { logger } from "../../loaders/logger"

You can see the runs of github actions to see the errors @ahnpnl

[ahnpnl]

Thanks a lot for the reproduce repo. I will take a look when there are some free times 👍

[ahnpnl]

I am having the same issue and using import {...} from "./module/index" doesn't work I need to specify the module when i import it. I create e minimal repo where I can reproduce it repo in master the problem exist but in this branch remove-import-from-index-export works well and the diff is

diff --git a/src/services/api/http.ts b/src/services/api/http.ts
index 80bd1a1..2f422c4 100644
--- a/src/services/api/http.ts
+++ b/src/services/api/http.ts
@@ -2,3 +2,3 @@ import axios, { AxiosRequestConfig, Method } from "axios"

-import { logger } from "../../loaders"
+import { logger } from "../../loaders/logger"

You can see the runs of github actions to see the errors @ahnpnl

hi @jyeros , I have checked your repo and indeed I can see the error. However, I don't think this is ts-jest issue. I have tested with babel-jest and saw the same issue so it's most likely about your codes not accepted by jest.

To test with babel-jest you can do these steps:

• Modify your transform option in jest.config.js

transform: {
    "^.+\\.ts?$": "babel-jest",
},

• Install babel-jest, @babel/preset-env, @babel/preset-typescript
• Create a babel.config.js with this content

module.exports = {
  presets: [
    [
      "@babel/preset-env",
      {
        targets: {
          node: "current",
        },
      },
    ],
    "@babel/preset-typescript",
  ],
}

• clear jest cache and rerun the test. You will see similar error

Test suite failed to run

    TypeError: (0 , _http.httpRequest) is not a function

      3 | import { httpRequest } from "../services/api/http"
      4 | 
    > 5 | const request = httpRequest({
        |                 ^
      6 |   url: "http://localhost:8080",
      7 |   headers: {
      8 |     Accept: "application/json",

      at Object.<anonymous> (src/routes/index.ts:5:17)
      at Object.<anonymous> (src/loaders/index.ts:6:1)

[ahnpnl]

close as this is not ts-jest problem. I have debugged ts-jest codes and everything went well. This is the problem of upstream jest.

[vicary]

@ahnpnl Adding to the context, some recent projects of mine in React Native seems do tests correctly, didn't have chance for a greenfield web project yet.

Since React Native typescript template uses jest directly, at least we know some version of it can handle these imports, upgrading dependent version in ts-jest may very well fix this.

[ahnpnl]

Oh it’s nice to hear that.

FYI the error comes from jest runtime, not typescript itself and ts-jest internal typescript compiler delivered the compiled js and jest runtime takes care of the rest.

Since it’s related to how jest runtime accepts the transpiled codes, ts-jest can’t do anything.