function test_DeleteAll() { //Arrange $name = "Math"; $course_number = "112"; $test_course = new course($name, $course_number); $test_course->save(); $name2 = "The Same Exact Name"; $course_number2 = "112"; $test_course2 = new course($name2, $course_number2); $test_course2->save(); course::deleteAll(); $result = course::getAll(); $this->assertEquals([], $result); }