vlib/v/checker/tests/unimplemented_interface_d.vv:12:6: error: `Cat` incorrectly implements method `speak` of interface `Animal`: expected 2 parameter(s), not 1
   10 |
   11 | fn main() {
   12 |     foo(Cat{})
      |         ~~~~~
   13 | }
Details: main.Animal has `fn speak(x main.Animal, s string)`
         main.Cat has `fn speak(c main.Cat)`