Golang: How to reuse test code in imported package?

Here is my directory hierarchy:

/
|-- main.go // package main
|-- main_test.go
|-- pkg1 // package pkg1
    |-- pkg1_test.go

I have some utility functions for tests only in pkg1_test.go. main.go imports pkg1. Now I want to use these functions in my main_test.go. After searching I found two possible solutions, but both of them have some drawbacks:

• Move these functions into pkg1.go. However these functions might be contained in binaries generated by go build.
• Move these functions into a separate testutility package, then import it in *_test.go manually. The problem is that these functions use some internal methods in pkg1.

So I was wondering whether there is a better solution to this problem.