public function test_set_problem_set() { $q = self::factory()->question->create(); $question = new \WeBWorK\Server\Question($q); $problem_set = 'foo'; $question->set_problem_set($problem_set); $this->assertTrue($question->save()); $question2 = new \WeBWorK\Server\Question($q); $this->assertSame($problem_set, $question2->get_problem_set()); }