Test stubbing a method of a local interface.
It works so long as the methods have no free type parameters.

-- go.mod --
module example.com

go 1.18

-- a/a.go --
package a

func f[T any]() {
	// nope: method C.f(T) would have a free type param, T.
	type I interface{ f(T) }
	var _ I = C(0) //@quickfixerr(re"C", re"missing method", re"found 0 CodeActions")

	// ok: method C.f(int) is fine.
	type J interface{ f(int) }
	var _ J = C(0) //@quickfix(re"C", re"missing method", out)
}

type C int

-- @out/a/a.go --
@@ -15 +15,4 @@
+// f implements [J].
+func (c C) f(int) {
+	panic("unimplemented")
+}

