tanakahisateru/AssertHtmlTarit.php

## AssertHtmlTarit.php
<?php
/**
 * @method assertEquals(mixed $expected, mixed $actual, string $message)
 */
trait AssetHtmlTrait
{
    public function assertHtmlStringEqualsHtmlString(string $expectedHtml, string $actualHtml, string $message = ''): void
    {
        $expected = (new \PHPUnit\Util\Xml\Loader)->load(
            $this->cleanHtml($expectedHtml),
            true
        );
        $actual = (new \PHPUnit\Util\Xml\Loader)->load(
            $this->cleanHtml($actualHtml),
            true
        );
        $this->assertEquals($expected, $actual, $message);
    }

    protected function cleanHtml(string $html): string
    {
        $html = preg_replace(['/>\s+/', '/\s+</'], ['>', '<'], $html);
        return preg_replace('/\s+/', ' ', $html);
    }
}

## ExampleTest.php
<?php
class ExampleTest
{
    use AssetHtmlTrait;

    public function testSomeOperation()
    {
        $actual = sprintf(<<<HTML
            <div><a href="%s" title="%s">link</a></div>
        HTML, "https://example.com", "example.com");

        // You can check HTML equivalence:
        $this->assertHtmlStringEqualsHtmlString(<<<HTML
            <div>
                <a
                    title="example.com"
                    href="https://example.com"
                >link</a>
            </div>
        HTML), $actual);
    }
}
	<?php
	/**
	* @method assertEquals(mixed $expected, mixed $actual, string $message)
	*/
	trait AssetHtmlTrait
	{
	public function assertHtmlStringEqualsHtmlString(string $expectedHtml, string $actualHtml, string $message = ''): void
	{
	$expected = (new \PHPUnit\Util\Xml\Loader)->load(
	$this->cleanHtml($expectedHtml),
	true
	);
	$actual = (new \PHPUnit\Util\Xml\Loader)->load(
	$this->cleanHtml($actualHtml),
	true
	);
	$this->assertEquals($expected, $actual, $message);
	}

	protected function cleanHtml(string $html): string
	{
	$html = preg_replace(['/>\s+/', '/\s+</'], ['>', '<'], $html);
	return preg_replace('/\s+/', ' ', $html);
	}
	}
	<?php
	class ExampleTest
	{
	use AssetHtmlTrait;

	public function testSomeOperation()
	{
	$actual = sprintf(<<<HTML
	<div><a href="%s" title="%s">link</a></div>
	HTML, "https://example.com", "example.com");

	// You can check HTML equivalence:
	$this->assertHtmlStringEqualsHtmlString(<<<HTML
	<div>
	<a
	title="example.com"
	href="https://example.com"
	>link</a>
	</div>
	HTML), $actual);
	}
	}