error: "alias" attribute must be a string literal
 --> tests/ui/non_string_alias.rs:6:10
  |
6 | #[derive(SerializeLabeledStringEnum, DeserializeLabeledStringEnum)]
  |          ^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: this error originates in the derive macro `SerializeLabeledStringEnum` (in Nightly builds, run with -Z macro-backtrace for more info)

error: "alias" attribute must be a string literal
 --> tests/ui/non_string_alias.rs:6:38
  |
6 | #[derive(SerializeLabeledStringEnum, DeserializeLabeledStringEnum)]
  |                                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  |
  = note: this error originates in the derive macro `DeserializeLabeledStringEnum` (in Nightly builds, run with -Z macro-backtrace for more info)