message: Unit test migration
diff: @@ -277,6 +277,41 @@ mod tests {
  assert_eq!(query_response.as_slice(), b"{\"verifier\":\"verifies\"}");
  }
  + #[test]
  + fn migrate_verifier() {
  + let mut deps = mock_dependencies(20, &[]);
  +
  + let verifier = HumanAddr::from("verifies");
  + let beneficiary = HumanAddr::from("benefits");
  + let creator = HumanAddr::from("creator");
  + let msg = InitMsg {
  + verifier: verifier.clone(),
  + beneficiary,
  + };
  + let env = mock_env(&deps.api, creator.as_str(), &[]);
  + let res = init(&mut deps, env, msg).unwrap();
  + assert_eq!(0, res.messages.len());
  +
  + // check it is 'verifies'
  + let query_response = query(&deps, QueryMsg::Verifier {}).unwrap();
  + assert_eq!(query_response.as_slice(), b"{\"verifier\":\"verifies\"}");
  +
  + // change the verifier via migrate
  + let msg = MigrateMsg {
  + verifier: HumanAddr::from("someone else"),
  + };
  + let env = mock_env(&deps.api, creator.as_str(), &[]);
  + let res = migrate(&mut deps, env, msg).unwrap();
  + assert_eq!(0, res.messages.len());
  +
  + // check it is 'someone else'
  + let query_response = query(&deps, QueryMsg::Verifier {}).unwrap();
  + assert_eq!(
  + query_response.as_slice(),
  + b"{\"verifier\":\"someone else\"}"
  + );
  + }
  +
  #[test]
  fn querier_callbacks_work() {
  let rich_addr = HumanAddr::from("foobar");
  