function ThemeTest::testAttributeMerging

Tests attribute merging.

Render arrays that use a render element and templates (and hence call template_preprocess()) must ensure the attributes at different occasions are all merged correctly:

• $variables['attributes'] as passed in to the theme hook implementation.
• the render element's #attributes
• any attributes set in the template's preprocessing function

File

core/modules/system/tests/src/Kernel/Theme/ThemeTest.php, line 40

Class

ThemeTest

Tests low-level theme functions.

Namespace

Code

public function testAttributeMerging() : void {
    $theme_test_render_element = [
        'elements' => [
            '#attributes' => [
                'data-foo' => 'bar',
            ],
        ],
        'attributes' => [
            'id' => 'some_attribute',
        ],
    ];
    $this->assertThemeOutput('theme_test_render_element', $theme_test_render_element, '<div id="some_attribute" data-foo="bar" data-variables-are-preprocessed></div>' . "\n");
}