--- /dev/null
+<?php
+
+namespace Drupal\Tests;
+
+use Drupal\Core\Render\Markup;
+
+/**
+ * @coversDefaultClass \Drupal\Tests\AssertHelperTrait
+ * @group simpletest
+ * @group Tests
+ */
+class AssertHelperTraitTest extends UnitTestCase {
+
+ /**
+ * @covers ::castSafeStrings
+ * @dataProvider providerCastSafeStrings
+ */
+ public function testCastSafeStrings($expected, $value) {
+ $class = new AssertHelperTestClass();
+ $this->assertSame($expected, $class->testMethod($value));
+ }
+
+ public function providerCastSafeStrings() {
+ $safe_string = Markup::create('test safe string');
+ return [
+ ['test simple string', 'test simple string'],
+ [['test simple array', 'test simple array'], ['test simple array', 'test simple array']],
+ ['test safe string', $safe_string],
+ [['test safe string', 'test safe string'], [$safe_string, $safe_string]],
+ [['test safe string', 'mixed array', 'test safe string'], [$safe_string, 'mixed array', $safe_string]],
+ ];
+ }
+
+}
+
+class AssertHelperTestClass {
+ use AssertHelperTrait;
+
+ public function testMethod($value) {
+ return $this->castSafeStrings($value);
+ }
+
+}