I'm having an issue when trying to pass an output to an intrinsic function

the argument to Fn::ToBase64 must be a string; the argument to Fn::ToBase64 must be a string

the variables section is:

variables:
  kubeconfigs:
    Fn::Invoke:
      Function: azure-native:containerservice:listManagedClusterUserCredentials
      Arguments:
        resourceGroupName: ${rg.name}
        resourceName: ${cluster-1.name}
  kubeconfigb64:
    Fn::ToBase64: ${kubeconfigs.kubeconfigs[0].value}

the outputs section is as such

outputs:
  kconfig: ${kubeconfigs.kubeconfigs[0].value}

the output is:

Outputs:
  + kconfig: "YXBpVmVyc2lv................................................."

Meant to post internally? 🙂

wanted to post it here just in case it helps a community member

we had unit tests to allow it to take an expression, but the tests used the abstract syntax tree and not the parser 😕 https://github.com/pulumi/pulumi-yaml/pull/221