gistfile1.php

<?php

class SampleTest extends WP_UnitTestCase {

	function test_sample() {

		$args = array(
			'public' => true,
			'label'  => 'Books'
		);
		register_post_type( 'book', $args );

		$pre = get_post_type_object( 'book' )->labels;

		get_post_type_labels( get_post_type_object( 'book' ) );

		$post = get_post_type_object( 'book' )->labels;

		$this->assertEquals( $pre, $post );
	}
}