in plasma-store/src/ffi/tests.rs [22:28]
fn plasma_ffi_oid_roundtrip() {
let oid: UniquePtr<ffi::ObjectID> = get_random_oid();
let bin = ffi::oid_to_binary(&oid);
let oid_deser = ffi::oid_from_binary(&bin);
assert!(ffi::oid_equals(&oid, &oid_deser));
assert_eq!(bin, ffi::oid_to_binary(&oid_deser));
}