Helpers

Mantle provides some testing helpers to make it easier to write tests for your project.

HTML String

The Mantle\Testing\html_string helper is used to create a DOMDocument object from an HTML string. This can be useful when you need to test a function that returns HTML output and want to make assertions about the generated HTML. You can use the same methods as the Element Assertions feature to make assertions about the HTML string.

use Mantle\Testing\html_string;

html_string(
  '
	<div>
		<section>Example Section</section>
		<div class="test-class">Example Div By Class</div>
		<div id="test-id">Example Div By ID</div>
		<ul>
			<li>Item 1</li>
			<li>Item 2</li>
			<li data-testid="test-item">Item 3</li>
		</ul>
	</div>
  '
)
  ->assertContains( 'Example Section' )
  ->assertElementExists( '//section' )
  ->assertQuerySelectorExists( 'section' )
  ->assertElementExistsById( 'test-id' )
  ->assertElementExistsByTestId( 'test-item' );

The HTML string helper returns a HTML object.

Getting Output

\Mantle\Testing\Utils::get_echo() is a replacement for the core WordPress test suite's get_echo() function. It takes a callable, starts an output buffer, calls the given callable, and returns the contents of the output buffer. Example:

use Mantle\Testing\Utils;

$demo   = Utils::get_echo( fn ( $subject ) => echo "Hello {$subject}!", 'world' );
$title  = Utils::get_echo( 'the_title' );
$method = Utils::get_echo( [ 'My_Class', 'method_that_outputs' ] );