jest test file import sweetalert2 will report css error - jestjs

Question

I have run this repo using jest test tool
jest config in package.json
"jest": {
"moduleNameMapper": {
"\\.(jpg|jpeg|png|gif|eot|otf|webp|svg|ttf|woff|woff2|mp4|webm|wav|mp3|m4a|aac|oga)$": "<rootDir>/reactTests/__mocks__/fileMock.js",
"\\.(css|less)$": "<rootDir>/client/src/stylesheets/"
},
"testPathIgnorePatterns": [
"<rootDir>/node_modules/",
"<rootDir>/client/src/stylesheets/"
]
}
project directory
.project
+-- client
| +-- stylesheets
| | +-- style.css
| | +-- preloader.gif
+-- reactTests
| +-- __mocks__
| | +-- fileMock.js
the file fileMock.js
module.exports = 'test-file-stub';
.babelrc
{
"presets": [
["env", { "modules": false }],
"es2015",
"react",
"stage-2"
],
"plugins": ["transform-class-properties"]
}
test file is teamAmerica.test.js
import React from 'react';
import renderer from 'react-test-renderer';
/**
*
*
* import sweetalert2 seems to report css error
* remove all is well
*
*
*/
// import swa from 'sweetalert2';
import { TeamAmerica } from './../../client/src/components/TeamAmerica';
// I had to copy paste the API json into this file to fix a bug
const team = {
presidents: [
{
team: 'Presidents',
team_id: '1',
first_name: 'George',
full_name: 'George Washington',
last_name: 'Washington',
role: 'First President of the United State of America.',
},
{
team: 'Presidents',
team_id: '2',
first_name: 'Abraham',
full_name: 'Abraham Lincoln',
last_name: 'Lincoln',
role: 'President during the Civil War.',
},
{
team: 'Presidents',
team_id: '3',
first_name: 'Franklin D.',
full_name: 'Franklin D. Roosevelt',
last_name: 'Roosevelt',
role: 'President during The Great Depression and WW2. Only president to be elected 4 times.',
},
],
client: [
{
team: 'US People',
team_id: '2',
first_name: 'Joe',
full_name: 'Joe Sixpack',
last_name: 'Sixpack',
role: 'Average American',
},
],
};
// I was getting an error that getTeam was not a function, so I had to turn it into a function in the test by doing this fat arrow
const getTeam = () => {};
// This is the actual test written for Jest
it('test to see if the team renders correctly', () => {
const tree = renderer
.create(<TeamAmerica getTeam={getTeam} team={[team.presidents]} />)
.toJSON();
expect(tree).toMatchSnapshot();
});
In the test file I have added import swal from 'sweetalert2' If remove this line and run npm run test the error will be gone otherwise the error show.
Can someone help to solve this problem?