test-methods.js

function describe( testString, tests ) {
	console.group( testString );
	tests();
	console.groupEnd();
}

function it( testString, test ) {
	let testResult = test();
	let color = ( false === testResult.result ) ? 'red' : 'green';

	console.log( `%c ${testString} ${testResult.message}`, `color:${color}` );
}

function assertEquals( value1, value2 ) {
	let message = '';
	let expression = value1 % value2 < 1;

	if ( false === expression ) {
		message = '\n \t Fail: ' + (value1 % value2).toFixed(1);
	}

	return {
		result: expression,
		message: message
	};
}

function assertGreaterThan( value1, value2 ) {
	let message = '';
	let expression = value1 > value2;

	if ( false === expression ) {
		message = '\n \t Fail: ' + (value1 % value2).toFixed(1);
	}

	return {
		result: expression,
		message: message
	};
}

function $( selector ) {
	return document.querySelector( selector );
}

function getCustomPropertyValue( selector, propertyName ) {
	return window.getComputedStyle( $( selector ) ).getPropertyValue( propertyName );
}