[rbdr/forum] / src / lib / animations / blink.test.ts

/**
 * @jest-environment jsdom
 */

import { blink } from './blink';
import { sineOut } from 'svelte/easing';

const internals = {
        response: null
};

describe('blink', () => {
        test('it has a default delay of 0ms', () => {
                const response = blink(document.createElement('div'), {});

                expect(response.delay).toBe(0);
        });

        test('it allows delay to be overridden', () => {
                const response = blink(document.createElement('div'), {
                        delay: 300
                });

                expect(response.delay).toBe(300);
        });

        test('it has a default duration of 400ms', () => {
                const response = blink(document.createElement('div'), {});

                expect(response.duration).toBe(400);
        });

        test('it allows delay to be overridden', () => {
                const response = blink(document.createElement('div'), {
                        duration: 999
                });

                expect(response.duration).toBe(999);
        });

        test('it uses sineOut as the default easing function', () => {
                const response = blink(document.createElement('div'), {});

                expect(response.easing).toBe(sineOut);
        });

        test('it allows easing function to be overridden', () => {
                const response = blink(document.createElement('div'), {
                        easing: () => 666
                });

                expect(response.easing(0)).toBe(666);
        });

        describe('css animation function', () => {
                beforeEach(() => {
                        const div = document.createElement('div');
                        div.style.width = '100px';
                        div.style.height = '200px';
                        internals.response = blink(div, {});
                });

                test('It starts with with zeroed width and height', () => {
                        const css = internals.response.css(0, 1);
                        expect(css).toContain('width: 0px');
                        expect(css).toContain('height: 0px');
                });

                test('It grows to full height and 0 width in first 20%', () => {
                        const css = internals.response.css(0.2, 0.8);
                        expect(css).toContain('width: 0px');
                        expect(css).toContain('height: 200px');
                });

                test('It expands to full height by the end', () => {
                        const css = internals.response.css(1, 0);
                        expect(css).toContain('width: 100px');
                        expect(css).toContain('height: 200px');
                });

                test('It keeps element vertically centered by adjusting the margin', () => {
                        const css = internals.response.css(0.1, 0.9);
                        expect(css).toContain('margin: 50px 50px');
                        expect(css).toContain('height: 100px');
                });

                test('It keeps element horizontally centered by adjusting the margin', () => {
                        const css = internals.response.css(0.6, 0.4);
                        expect(css).toContain('margin: 0px 25px');
                        expect(css).toContain('width: 50px');
                });
        });
});