(diagnostic
  (schema slovo.diagnostic)
  (version 1)
  (severity error)
  (code TypeMismatch)
  (message "cannot call `std.string.byte_at_result` with argument of wrong type")
  (file "<fixture>")
  (span
    (bytes 83 86)
    (range 5 36 5 39)
  )
  (expected "i32")
  (found "string")
)