function `Difference` test failed

[AirbornWdd]

func TestIPSetDiff(t *testing.T) {
	var testAddrSet = []string{
		"10.1.1.0",
		"10.1.1.5",
		"10.1.1.6",
		"10.1.1.7",
		"10.1.1.8",
		"10.1.1.9",
		"10.1.1.10",
		"10.1.1.1",
		"10.1.1.2",
		"10.1.1.3",
		"10.1.1.4",
		"10.1.1.11",
		"10.1.1.12",
		"10.1.1.13",
		"10.1.1.14",
		"10.1.1.15",
	}

	n := &netaddr.IPSet{}
	o := &netaddr.IPSet{}

	_, ips, _ := net.ParseCIDR("10.1.1.0/28")
	n.InsertNet(ips)

	for _, ip := range testAddrSet {
		o.Insert(net.ParseIP(ip))
	}

	if d := n.Difference(o).String(); len(d) != 0 {
		t.Fatalf("diff: %s", d)
	}
}

[ecbaldwin]

This project is effectively dead at IBM. There is an alternative in development here: https://pkg.go.dev/gopkg.in/addrs.v0

This test passes with that library. I translated it like this:

package main

import (
	"net"
	"testing"

	"gopkg.in/addrs.v0/ipv4"
	"github.com/stretchr/testify/assert"
)

func TestIPSetDiff(t *testing.T) {
	var testAddrSet = []string{
		"10.1.1.0",
		"10.1.1.5",
		"10.1.1.6",
		"10.1.1.7",
		"10.1.1.8",
		"10.1.1.9",
		"10.1.1.10",
		"10.1.1.1",
		"10.1.1.2",
		"10.1.1.3",
		"10.1.1.4",
		"10.1.1.11",
		"10.1.1.12",
		"10.1.1.13",
		"10.1.1.14",
		"10.1.1.15",
	}

	n := ipv4.NewSet()
	o := ipv4.NewSet()

	_, ips, _ := net.ParseCIDR("10.1.1.0/28")
	prefix, err := ipv4.PrefixFromNetIPNet(ips)
	assert.Nil(t, err)
	n.Insert(prefix)

	for _, ip := range testAddrSet {
		addr, err := ipv4.AddressFromNetIP(net.ParseIP(ip))
		assert.Nil(t, err)
		o.Insert(addr)
	}

	assert.Equal(t, int64(0), n.Difference(o).Size())
}