"Navbar refers to a value, but is being used as a type here" when trying to render a shallow copy of my component when testing

Question

I am trying to write a test to my React component, using TypeScript, Jest as my test runner and Enzyme for testing my React components. Whenever I pass my component into the shallow Enzyme function, I get the ts error "'Navbar' refers to a value, but is being used as a type here.", and underneath I get eslint error "Parsing error: '>' expected".

I tried it on some other components, all have the same error when being passed into the shallow function as arguments. I suspect it may have something to do with my TS configurations, but for the life of me I cannot seem to be finding a solution.

Here's the code for Navbar.tsx:

import React from 'react';
import { shallow } from 'enzyme';
import Navbar from './Navbar';

describe('Navbar component', () => {
    let component;
    beforeEach(() => {
        component = shallow(<Navbar />); // Error being desplayed here
    });

    it('should render without errors', () => {
        expect(component).toMatchInlineSnapshot();
        expect(component.length).toBe(1);
        expect(component).toBeTruthy();
    });
});

Also posting my config files:

tsconfig:

{
  "compilerOptions": {
    "target": "es5",
    "lib": [
      "dom",
      "dom.iterable",
      "esnext"
    ],
    "allowJs": true,
    "skipLibCheck": true,
    "esModuleInterop": true,
    "allowSyntheticDefaultImports": true,
    "strict": true,
    "forceConsistentCasingInFileNames": true,
    "module": "esnext",
    "moduleResolution": "node",
    "resolveJsonModule": true,
    "isolatedModules": true,
    "noEmit": true,
    "jsx": "react"
  },
  "parserOptions": {
    "ecmaVersion": 6,
    "sourceType": "module",
    "ecmaFeatures": {
      "jsx": true
    }
  },
  "include": ["src/**/*"],
  "exclude": ["node_modules", "**/*.spec.ts", "**/*.test.ts"]
}

jest.config.ts:

module.exports = {
    roots: ['<rootDir>/src'],
    transform: {
        '^.+\\.tsx?$': 'ts-jest',
    },
    testRegex: '(/__tests__/.*|(\\.|/)(test|spec))\\.tsx?$',
    moduleFileExtensions: ['ts', 'tsx', 'js', 'jsx', 'json', 'node'],
    snapshotSerializers: ['enzyme-to-json/serializer'],
    setupTestFrameworkScriptFile: '<rootDir>/src/setupEnzyme.ts',
};

Enzyme setup:

import { configure } from 'enzyme';
import Adapter from 'enzyme-adapter-react-16';
import 'jest-enzyme';

configure({ adapter: new Adapter(), disableLifecycleMethods:

Is it a good idea to exclude the "test" directory in the tsconfig.json? — user805981
Just wondering, do you really need beforeEach()? Why not move the assignment to the top level: const component = shallow(<Navbar />); // Error being desplayed here — kawerewagaba

Ernesto Ernesto · Accepted Answer · 2019-10-11T13:39:12

Have you tried to change the name of the file? MyComponent.test.tsx Also, did you install the types of jest and stuff npm i -D @types/jest. I mean I’m saying this because if you look at the jest config where it says testRegex. You have it like this __tests__/*.(test|spec).txs the test must be inside a tests folder and it has to have the name: MyComponent.test.tsx

"Navbar refers to a value, but is being used as a type here" when trying to render a shallow copy of my component when testing

2 Answers