Nim/tests/pragmas/tlocks.nim

type SomeBase* = ref object of RootObj
type SomeDerived* = ref object of SomeBase
  memberProc*: proc ()

method testMethod(g: SomeBase) {.base, locks: "unknown".} = discard
method testMethod(g: SomeDerived) =
  if g.memberProc != nil:
    g.memberProc()

# ensure int literals still work
proc plain*() {.locks: 0.} =
  discard