net/tstun: rename NewFakeTUN to NewFake.

Signed-off-by: David Anderson <danderson@tailscale.com>

cmd/tailscaled/tailscaled.go

@@ -333,7 +333,7 @@ func tryEngine(logf logger.Logf, linkMon *monitor.Mon, name string) (e wgengine.
 	}
 	isUserspace = name == "userspace-networking"
 	if isUserspace {
-		conf.TUN = tstun.NewFakeTUN()
+		conf.TUN = tstun.NewFake()
 		conf.Router = router.NewFake(logf)
 	} else {
 		dev, err := tstun.New(logf, name)

net/tstun/fake.go

@@ -16,10 +16,8 @@ type fakeTUN struct {
 	closechan chan struct{}
 }
 
-// NewFakeTUN returns a fake TUN device that does not depend on the
+// NewFake returns a tun.Device that does nothing.
-// operating system or any special permissions.
+func NewFake() tun.Device {
-// It primarily exists for testing.
-func NewFakeTUN() tun.Device {
 	return &fakeTUN{
 		evchan:    make(chan tun.Event),
 		closechan: make(chan struct{}),

net/tstun/wrap_test.go

@@ -132,7 +132,7 @@ func newChannelTUN(logf logger.Logf, secure bool) (*tuntest.ChannelTUN, *TUN) {
 }
 
 func newFakeTUN(logf logger.Logf, secure bool) (*fakeTUN, *TUN) {
-	ftun := NewFakeTUN()
+	ftun := NewFake()
 	tun := WrapTUN(logf, ftun)
 	if secure {
 		setfilter(logf, tun)

wgengine/userspace.go

@@ -156,7 +156,7 @@ type Config struct {
 func NewFakeUserspaceEngine(logf logger.Logf, listenPort uint16) (Engine, error) {
 	logf("Starting userspace wireguard engine (with fake TUN device)")
 	return NewUserspaceEngine(logf, Config{
-		TUN:        tstun.NewFakeTUN(),
+		TUN:        tstun.NewFake(),
 		Router:     router.NewFake(logf),
 		ListenPort: listenPort,
 		Fake:       true,