Add unit test for the driver.

[ShotaAk]

What does this implement/fix?

Does this close any currently open issues?

How has this been tested?

Any other comments?

Checklists

• I have read the CONTRIBUTING guidelines.
  • If there is no guideline in the repository, rt-net organization's guideline applies.
• I have checked to ensure there aren't other open Pull Requests for the same change.

[ShotaAk]

他PRで対応済みのためクローズします。