wordpress-develop/tests/phpunit/tests/walker.php

<?php

/**
 * @group post
 * @group menu
 * @group taxonomy
 * @group walker
 */
class Tests_Walker extends WP_UnitTestCase {

	function setUp() {

		$this->walker = new Walker_Test();

		parent::setUp();

	}

	function test_single_item() {

		$items  = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
		);
		$output = $this->walker->walk( $items, 0 );

		$this->assertSame( 1, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1</li>', $output );

	}

	function test_single_item_flat() {

		$items  = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
		);
		$output = $this->walker->walk( $items, -1 );

		$this->assertSame( 1, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1</li>', $output );

	}

	function test_single_item_depth_1() {

		$items  = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
		);
		$output = $this->walker->walk( $items, 1 );

		$this->assertSame( 1, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1</li>', $output );

	}

	function test_multiple_items_single_level() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
			(object) array(
				'id'     => 2,
				'parent' => 0,
			),
		);

		$output = $this->walker->walk( $items, 0 );

		$this->assertSame( 2, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1</li><li>2</li>', $output );

	}

	function test_multiple_items_multiple_levels() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
			(object) array(
				'id'     => 2,
				'parent' => 1,
			),
		);

		$output = $this->walker->walk( $items, 0 );

		$this->assertSame( 1, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1<ul><li>2</li></ul></li>', $output );

	}

	function test_multiple_items_multiple_levels_flat() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
			(object) array(
				'id'     => 2,
				'parent' => 1,
			),
		);

		$output = $this->walker->walk( $items, -1 );

		$this->assertSame( 1, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1</li><li>2</li>', $output );

	}

	function test_multiple_items_multiple_levels_depth_1() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
			(object) array(
				'id'     => 2,
				'parent' => 1,
			),
		);

		$output = $this->walker->walk( $items, 1 );

		$this->assertSame( 1, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1</li>', $output );

	}

	function test_multiple_items_multiple_levels_depth_2() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 0,
			),
			(object) array(
				'id'     => 2,
				'parent' => 1,
			),
			(object) array(
				'id'     => 3,
				'parent' => 2,
			),
		);

		$output = $this->walker->walk( $items, 2 );

		$this->assertSame( 1, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1<ul><li>2</li></ul></li>', $output );

	}

	function test_multiple_items_recursive() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 2,
			),
			(object) array(
				'id'     => 2,
				'parent' => 1,
			),
		);

		$output = $this->walker->walk( $items, 0 );

		$this->assertSame( 0, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1<ul><li>2</li></ul></li>', $output );

	}

	function test_single_item_child() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 3,
			),
		);

		$output = $this->walker->walk( $items, 0 );

		$this->assertSame( 0, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>1</li>', $output );

	}

	function test_single_item_missing_parent_depth_1() {

		$items = array(
			(object) array(
				'id'     => 1,
				'parent' => 3,
			),
		);

		$output = $this->walker->walk( $items, 1 );

		$this->assertSame( 0, $this->walker->get_number_of_root_elements( $items ) );

		// It's not clear what the output of this "should" be.

		// Currently the item is simply returned.
		$this->assertSame( '<li>1</li>', $output );

		// But as we've only asked for the first depth maybe nothing should be returned?
		// $this->assertSame( '', $output );

	}

	function test_multiple_items_missing_parents() {

		$items = array(
			(object) array(
				'id'     => 4,
				'parent' => 1,
			),
			(object) array(
				'id'     => 5,
				'parent' => 2,
			),
			(object) array(
				'id'     => 6,
				'parent' => 3,
			),
		);

		$output = $this->walker->walk( $items, 0 );

		$this->assertSame( 0, $this->walker->get_number_of_root_elements( $items ) );
		$this->assertSame( '<li>4</li><li>5</li><li>6</li>', $output );

	}

	function test_multiple_items_missing_parents_depth_1() {

		$items = array(
			(object) array(
				'id'     => 4,
				'parent' => 1,
			),
			(object) array(
				'id'     => 5,
				'parent' => 2,
			),
			(object) array(
				'id'     => 6,
				'parent' => 3,
			),
		);

		$output = $this->walker->walk( $items, 1 );

		$this->assertSame( 0, $this->walker->get_number_of_root_elements( $items ) );

		// It's not clear what the output of this "should" be.

		// Currently the first item is simply returned.
		$this->assertSame( '<li>4</li>', $output );

		// But as we've only asked for the first depth maybe nothing should be returned?
		// $this->assertSame( '', $output );

		// Or maybe all items which are missing parents should simply be treat top level?
		// $this->assertSame( '<li>4</li><li>5</li><li>6</li>', $output );

	}

}

class Walker_Test extends Walker {

	public $tree_type = 'test';
	public $db_fields = array(
		'parent' => 'parent',
		'id'     => 'id',
	);

	function start_lvl( &$output, $depth = 0, $args = array() ) {
		$output .= '<ul>';
	}

	function end_lvl( &$output, $depth = 0, $args = array() ) {
		$output .= '</ul>';
	}

	function start_el( &$output, $item, $depth = 0, $args = array(), $current_page = 0 ) {
		$output .= '<li>' . $item->id;
	}

	function end_el( &$output, $page, $depth = 0, $args = array() ) {
		$output .= '</li>';
	}

}