public function test_create_classroom_matter_with_student_completed()
{
$classroomMatter = factory(ClassroomMatter::class)->create();
$student = factory(Student::class)->create();
$classroomMatter->studentCompletds()->attach($student);
$this->assertInstanceOf(Student::class, $classroomMatter->studentCompletds()->first());
$this->seeInDatabase('classroom_matter_student_completed', ['classroom_matter_id' => $classroomMatter->id, 'student_id' => $student->id]);
}