eg.go

package eg

func foo() string {
	return "foo"
}

func Bar() string {
	return "Bar"
}

eg_test.go

package eg_test

import (
	. "."
	"testing"
	)

func TestFunc(t *testing.T) {
	result := Foo()
	if result != "foo" {
		t.Errorf("result = %v, want %v", result, "foo")
	}
}

example_test.go

package eg_test

import (
	"."
	"fmt"
)

func ExampleCall() {
	fmt.Println(eg.Bar())
}

export_test.go

package eg

var Foo = foo

golang-package-example.md

golang package example with testing