Simple test which fails if code is not in the go format. Include this code in your package and code contributions will fail if not submitted with the correct format.

format_test.go

// include package name here

import (
	"bytes"
	"fmt"
	"os/exec"
	"testing"
)

func TestCodeFormattedCorrectly(t *testing.T) {
	cmd := exec.Command("gofmt", "-l", ".")
	var out bytes.Buffer
	cmd.Stdout = &out
	err := cmd.Run()
	if err != nil {
	    t.Error(fmt.Sprintf("Unexpected Error %v", err))
	}
	if out.String() != "" {
	    t.Error(fmt.Sprintf("Please run gofmt. The following files are in the wrong format: %v", out.String()))
	}
}