fonteva-design-guide/force-app/main/default/lwc/pfmButton/__tests__/pfmButtonTest.js

## Dev, Build and Test

import { createElement } from 'lwc';

import BUTTON from 'c/pfmButton';

describe('c-pfm-button', () => {
    afterEach(() => {
        // The jsdom instance is shared across test cases in a single file so reset the DOM
        while (document.body.firstChild) {
            document.body.removeChild(document.body.firstChild);
        }
    });

    it('start button loader', () => {
        const element = createElement('c-pfm-button', {
            is: BUTTON
        });

        document.body.appendChild(element);

        // Verify button loader
        element.startLoader();
        const loader = element.shadowRoot.querySelector('.js-load');

        expect(loader).not.toBeNull();
    });

    it('stop button loader', () => {
        const element = createElement('c-pfm-button', {
            is: BUTTON
        });

        document.body.appendChild(element);

        // Verify button loader
        element.startLoader();
        element.endLoader();
        const loader = element.shadowRoot.querySelector('.js-load');
        expect(loader).toBeNull();
    });

    it('render button theme: danger', () => {
        const element = createElement('c-pfm-button', {
            is: BUTTON
        });

        element.theme = 'danger';
        document.body.appendChild(element);

        // Verify theme
        setTimeout(() => {
            const theme = element.shadowRoot.querySelector('button').classList.contains('pfm-button_danger');
            expect(theme).toBeFalsy();
        }, 5);
    });

    it('render button icon', () => {
        const element = createElement('c-pfm-button', {
            is: BUTTON
        });

        element.icon = 'utility:add';
        element.iconposition = 'left';
        document.body.appendChild(element);

        // Verify icon
        setTimeout(() => {
            const icon = element.shadowRoot.querySelector('lightning-icon');
            expect(icon).not.toBeNull();
        }, 5);
    });

    it('render button icon position', () => {
        const element = createElement('c-pfm-button', {
            is: BUTTON
        });

        element.icon = 'utility:add';
        element.iconPosition = 'right';
        document.body.appendChild(element);

        // Verify icon position
        const position = element.shadowRoot.querySelector('button > *:first-of-type');
        expect(position === 'span').toBeFalsy();
    });

    it('render a button w/ multiple additional classes', () => {
        const element = createElement('c-pfm-button', {
            is: BUTTON
        });

        element.additionalClasses = 'foo bar';
        document.body.appendChild(element);

        // Verify icon position
        setTimeout(() => {
            const btn = element.shadowRoot.querySelector('button.foo.bar');
            expect(btn).toBeTruthy();
        });
    });
});