veritatisquam/packages/core/src/components/essentials/legend.spec.ts

Carbon charting components, lerna monorepo

import { TestEnvironment } from '../../tests/index';

// import the settings for the css prefixes
import settings from 'carbon-components/es/globals/js/settings';

import { options } from './../../configuration';
import { Events } from './../../interfaces';

import { select } from 'd3-selection';

describe('legend component', () => {
	beforeEach(function () {
		const testEnvironment = new TestEnvironment();
		testEnvironment.render();

		this.chart = testEnvironment.getChartReference();
		this.testEnvironment = testEnvironment;
	});

	describe('content', () => {
		it('should have same amount of datasets', async function (done) {
			const data = this.testEnvironment.chartData;
			const uniqueDatagroups = data
				.map((d) => d.group)
				.filter(function (value, index, self) {
					return self.indexOf(value) === index;
				});

			const numberOfDatagroups = uniqueDatagroups.length;

			const chartEventsService = this.chart.services.events;

			const renderCb = () => {
				// Remove render event listener
				chartEventsService.removeEventListener(
					Events.Chart.RENDER_FINISHED,
					renderCb
				);

				const numberOfLegendItems = select(
					`g.${settings.prefix}--${options.chart.style.prefix}--legend`
				)
					.selectAll('g.legend-item')
					.size();
				expect(numberOfLegendItems).toEqual(numberOfDatagroups);

				done();
			};

			// Add event listener for when chart render is finished
			chartEventsService.addEventListener(
				Events.Chart.RENDER_FINISHED,
				renderCb
			);
		});
	});

	afterEach(function () {
		this.testEnvironment.destroy();
	});
});