digest = lambda value: hashlib.sha256(json.dumps(value, sort_keys=True, ensure_ascii=False).encode()).hexdigest()
snapshot = digest(data)
changed = {**data, 'capacity': data['capacity'] + 1}
check('原始输入对应预览可进入人工确认', snapshot == digest(data))
check('输入变更后旧预览被拦截', snapshot != digest(changed))
result = {'draft': output, 'input_hash': snapshot, 'saved': False, 'changed_input_can_save_old_draft': False}
