4223655829 Add test case (yancy)
Pull request description:
Since there are test cases for other functions here, add test case as follow up for https://github.com/rust-bitcoin/rust-bitcoin/pull/3604. I forgot to request this during review.
ACKs for top commit:
apoelstra:
ACK 422365582964cf405529de3a1cf63d766b0d0e2e; successfully ran local tests
tcharding:
ACK 4223655829
Tree-SHA512: 8629cfff3e3eb800aa4d4625627e0a777c389566f4125bc63e67fe4c5a597ca63b9fb92da42f6c9dab12e6c63839eef35a13957f98606a37ed687eb96d896c2e