When the packer configuration is separated across multiple .hcl files, Terratest does not initialise packer when Template in the packer.Options is set to ".". To get Terratest to initialise packer, I have to set Template to the path of a .hcl file.

Is there an additional setting I am missing from my packer options? Or, is a modification to terratest required?

packerOptions := &packer.Options{
  Template: ".",

  WorkingDir: ".",
}