You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: cache_test.go
    path of file: ./repos/syncthing/lib/discover
    
    the code of the file until where you have to start completion: // Copyright (C) 2015 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
    
func TestCacheUnique(t *testing.T) {
	addresses0 := []string{"tcp://192.0.2.44:22000", "tcp://192.0.2.42:22000"}
	addresses1 := []string{"tcp://192.0.2.43:22000", "tcp://192.0.2.42:22000"}

	// what we expect from just addresses0
	addresses0Sorted := []string{"tcp://192.0.2.42:22000", "tcp://192.0.2.44:22000"}

	// what we expect from addresses0+addresses1
	totalSorted := []string{
		"tcp://192.0.2.42:22000",
		// no duplicate .42
		"tcp://192.0.2.43:22000",
		"tcp://192.0.2.44:22000",
	}

	c := setupCache()

	// Add a fake discovery service and verify we get its answers through the
	// cache.

	f1 := &fakeDiscovery{addresses0}
	c.addLocked("f1", f1, time.Minute, 0)

	ctx := context.Background()

	addr, err := c.Lookup(ctx, protocol.LocalDeviceID)
	if err != nil {
		t.Fatal(err)
	}
	if !reflect.DeepEqual(addr, addresses0Sorted) {
		t.Errorf("Incorrect addresses; %+v != %+v", addr, addresses0Sorted)
	}

	// Add one more that answers in the same way and check that we don't
	// duplicate or otherwise mess up the responses now.

	f2 := &fakeDiscovery{addresses1}
	c.addLocked("f2", f2, time.Minute, 0)

	addr, err = c.Lookup(ctx, protocol.LocalDeviceID)
	if err != nil {
		t.Fatal(err)
	}
	if !reflect.DeepEqual(addr, totalSorted) {
		t.Errorf("Incorrect addresses; %+v != %+v", addr, totalSorted)
	}
}