parse_test.go: still display file name in case of error
parse_test.go: still display file name in case of error

tas50/packer,timsutton/packer,rnaveiras/packer,rnaveiras/packer,timsutton/packer,mitchellh/packer,ricardclau/packer,paulmey/packer,pecigonzalo/packer,bryson/packer,grubernaut/packer,pecigonzalo/packer,mitchellh/packer,bryson/packer,rnaveiras/packer,rnaveiras/packer,rnaveiras/packer,ricardclau/packer,hashicorp/packer,dave2/packer,timsutton/packer,bryson/packer,timsutton/packer,hashicorp/packer,grubernaut/packer,hashicorp/packer,ricardclau/packer,paulmey/packer,bryson/packer,grubernaut/packer,dave2/packer,dave2/packer,paulmey/packer,pecigonzalo/packer,grubernaut/packer,pecigonzalo/packer,tas50/packer,mitchellh/packer,mitchellh/packer,bryson/packer,mitchellh/packer,ricardclau/packer,rnaveiras/packer,dave2/packer,ricardclau/packer,timsutton/packer,dave2/packer,tas50/packer,ricardclau/packer,hashicorp/packer,paulmey/packer,paulmey/packer,tas50/packer,grubernaut/packer,dave2/packer,grubernaut/packer,tas50/packer,bryson/packer,tas50/packer,paulmey/packer,timsutton/packer