(diagnostic
  (schema slovo.diagnostic)
  (version 1)
  (severity error)
  (code TypeMismatch)
  (message "option `some` value has the wrong type")
  (file "<fixture>")
  (span
    (bytes 55 59)
    (range 5 13 5 17)
  )
  (expected "i32")
  (found "bool")
)