chef_vault_item_or_default method not working with kitchen mocked secret

[RvRivi]

For a secret defined in kitchen.yml like the following

- name: default
  run_list:
  - recipe[XXX]
  attributes:
    chef_secrets:
      fake:
        secret:
          user: password

the following code is raising an exception during the second if evaluation (if secret_with_default['user'] != 'password') whereas chef_vault_item_or_default() is expecting have the same behaviour than chef_vault_item() in that case

secret_with_default = chef_vault_item_or_default('fake', 'secret', 'default')
secret = chef_vault_item('fake', 'secret')

if secret['user'] != 'password'
  Chef::Log.info 'secret != password'
  raise
end

if secret_with_default['user'] != 'password'
  Chef::Log.info 'secret_with_default != password'
  raise
end

Please note this issue is only triggered in a kitchen test environment.