Mockgen emits bad code on empty interface (imported and not used: "reflect")

[SpikesDivZero]

When running against an empty interface, mockgen is writing out Go files that import the reflect library but don't actually use it causing an unexpected error during test execution:

imported and not used: "reflect"

A rough example input file is:

package tmp

//go:generate mockgen -pkg mocks -destination=../mockgen_tmp.go PACKAGE/tmp EmptyInterfacer

type EmptyInterfacer interface {
    // TODO
}

And all matching instances of reflect in the generated file:

mocks$ grep -C2 reflect mockgen_tmp.go
import (
    gomock "github.com/golang/mock/gomock"
    reflect "reflect"
)

mocks$ 

Adding any placeholder method to this interface makes the error go away.

And thanks for your work on this. It's a nice tool ^_^

[bamdadd]

I'm having this issue as well. If this gets fixed it helps with TDD process so that I can start with an empty interface and then add methods to the interface when needed.