error: Conflicting visibility for field 'id': cannot have both private and public fields with the same name
  --> tests/fail/private_field_conflict.rs:13:1
   |
13 | #[inject_fields(Base, Derived)]
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: this error originates in the attribute macro `inject_fields` (in Nightly builds, run with -Z macro-backtrace for more info)