An example of a common go package directory listing;

mypackage/
    - my_package.go
    - my_package_test.go
    - my_package_mock.go

It would be great if files with the suffix _mock.go were treated like files with the suffix _test.go in that they're only picked up by go test and not compiled when running go run or go build. This would mean that mocks could be stored in the same directory as the definitions that they mimic with meaningful names and not get compiled into production binaries.