Tests drupal_find_theme_templates().
public function testFindThemeTemplates() {
$cache = array();
// Prime the theme cache.
foreach (module_implements('theme') as $module) {
_theme_process_registry($cache, $module, 'module', $module, drupal_get_path('module', $module));
}
$templates = drupal_find_theme_templates($cache, '.html.twig', drupal_get_path('theme', 'test_theme'));
$this
->assertEqual($templates['node__1']['template'], 'node--1', 'Template node--1.html.twig was found in test_theme.');
}