How to use jest to compare an image to a pre-generated screenshot using an npm library called toMatchImageSnapshot

image-compare-jest-test.js

const { toMatchImageSnapshot } = require('jest-image-snapshot');
const path = require('path');
const fs = require('fs');
var gm = require("gm").subClass({imageMagick: true});;

jest.setTimeout(15000);
expect.extend({ toMatchImageSnapshot });

const imageAtTestPath = path.resolve(__dirname, '11c429f0-8bee-4c86-ab17-e04cf2bd2e11.jpeg');
const pngAtTestPath = path.resolve(__dirname, '11c429f0-8bee-4c86-ab17-e04cf2bd2e11.png');


test('image matches pre-generated snapshot', async () => {
    const pngStream = fs.readFileSync(pngAtTestPath);

    expect(pngStream).toMatchImageSnapshot();
});

test('image matches jpg snapshot', async (done) => {
    gm(imageAtTestPath).toBuffer('PNG', (error, buffer) => {
        expect(buffer).toMatchImageSnapshot();
        done();
    });
});