class FormatterPluginManagerTest

class FormatterPluginManagerTest extends FieldKernelTestBase {
    
    /**
     * Tests that getInstance falls back on default if current is not applicable.
     *
     * @see \Drupal\field\Tests\WidgetPluginManagerTest::testNotApplicableFallback()
     */
    public function testNotApplicableFallback() : void {
        
        /** @var \Drupal\Core\Field\FormatterPluginManager $formatter_plugin_manager */
        $formatter_plugin_manager = \Drupal::service('plugin.manager.field.formatter');
        $base_field_definition = BaseFieldDefinition::create('test_field')->setName('field_test_field');
        $formatter_options = [
            'field_definition' => $base_field_definition,
            'view_mode' => 'default',
            'configuration' => [
                'type' => 'field_test_applicable',
            ],
        ];
        $instance = $formatter_plugin_manager->getInstance($formatter_options);
        $this->assertEquals('field_test_applicable', $instance->getPluginId());
        // Now set name to something that makes isApplicable() return FALSE.
        $base_field_definition->setName('deny_applicable');
        $instance = $formatter_plugin_manager->getInstance($formatter_options);
        // Instance should be default widget.
        $this->assertNotSame('field_test_applicable', $instance->getPluginId());
        $this->assertEquals('field_test_default', $instance->getPluginId());
    }

}