lncfg: split off protocol options into normal and legacy, normal reqs no build tag

In this commit, we split off the protocol options into a normal and
legacy sub-config. The legacy sub-config protected by a built tag, and
will only be populated if thet tag is set. Legacy options now have a
`legacy` prefix. So `--protocol.legacyonion` is now `--protocol.onion`,
and `--protocol.committweak`, is now `--protocol.legacy.committweak`.

We also create a new experimental protocol feature sub-config for newer
features that may not yet been fully complete, so they require a build
tag.

lncfg/protocol.go

@@ -0,0 +1,15 @@
+package lncfg
+
+// ProtocolOptions is a struct that we use to be able to test backwards
+// compatibility of protocol additions, while defaulting to the latest within
+// lnd, or to enable experimental protocol changes.
+type ProtocolOptions struct {
+	// LegacyProtocol is a sub-config that houses all the legacy protocol
+	// options.  These are mostly used for integration tests as most modern
+	// nodes shuld always run with them on by default.
+	LegacyProtocol `group:"legacy" namespace:"legacy"`
+
+	// ExperimentalProtocol is a sub-config that houses any experimental
+	// protocol features that also require a build-tag to activate.
+	ExperimentalProtocol
+}

lncfg/protocol_experimental_off.go

@@ -0,0 +1,14 @@
+// +build !dev
+
+package lncfg
+
+// ExperimentalProtocol is a sub-config that houses any experimental protocol
+// features that also require a build-tag to activate.
+type ExperimentalProtocol struct {
+}
+
+// AnchorCommitments returns true if support for the anchor commitment type
+// should be signaled.
+func (l *ExperimentalProtocol) AnchorCommitments() bool {
+	return false
+}

lncfg/protocol_experimental_on.go

@@ -0,0 +1,17 @@
+// +build dev
+
+package lncfg
+
+// ExperimentalProtocol is a sub-config that houses any experimental protocol
+// features that also require a build-tag to activate.
+type ExperimentalProtocol struct {
+	// Anchors should be set if we want to support opening or accepting
+	// channels having the anchor commitment type.
+	Anchors bool `long:"anchors" description:"EXPERIMENTAL: enable experimental support for anchor commitments, won't work with watchtowers"`
+}
+
+// AnchorCommitments returns true if support for the anchor commitment type
+// should be signaled.
+func (l *ExperimentalProtocol) AnchorCommitments() bool {
+	return l.Anchors
+}

lncfg/protocol_legacy_off.go

@@ -2,27 +2,21 @@
 
 package lncfg
 
-// ProtocolOptions is a struct that we use to be able to test backwards
-// compatibility of protocol additions, while defaulting to the latest within
-// lnd, or to enable experimental protocol changes.
-type ProtocolOptions struct {
+// Legacy is a sub-config that houses all the legacy protocol options.  These
+// are mostly used for integration tests as most modern nodes shuld always run
+// with them on by default.
+type LegacyProtocol struct {
 }
 
 // LegacyOnion returns true if the old legacy onion format should be used when
 // we're an intermediate or final hop. This controls if we set the
 // TLVOnionPayloadOptional bit or not.
-func (l *ProtocolOptions) LegacyOnion() bool {
+func (l *LegacyProtocol) LegacyOnion() bool {
 	return false
 }
 
 // NoStaticRemoteKey returns true if the old commitment format with a tweaked
 // remote key should be used for new funded channels.
-func (l *ProtocolOptions) NoStaticRemoteKey() bool {
-	return false
-}
-
-// AnchorCommitments returns true if support for the the anchor commitment type
-// should be signaled.
-func (l *ProtocolOptions) AnchorCommitments() bool {
+func (l *LegacyProtocol) NoStaticRemoteKey() bool {
 	return false
 }

lncfg/protocol_legacy_on.go

@@ -2,41 +2,31 @@
 
 package lncfg
 
-// ProtocolOptions is a struct that we use to be able to test backwards
-// compatibility of protocol additions, while defaulting to the latest within
-// lnd, or to enable experimental protocol changes.
-type ProtocolOptions struct {
+// Legacy is a sub-config that houses all the legacy protocol options.  These
+// are mostly used for integration tests as most modern nodes shuld always run
+// with them on by default.
+type LegacyProtocol struct {
 	// LegacyOnionFormat if set to true, then we won't signal
 	// TLVOnionPayloadOptional. As a result, nodes that include us in the
 	// route won't use the new modern onion framing.
-	LegacyOnionFormat bool `long:"legacyonion" description:"force node to not advertise the new modern TLV onion format"`
+	LegacyOnionFormat bool `long:"onion" description:"force node to not advertise the new modern TLV onion format"`
 
 	// CommitmentTweak guards if we should use the old legacy commitment
 	// protocol, or the newer variant that doesn't have a tweak for the
 	// remote party's output in the commitment. If set to true, then we
 	// won't signal StaticRemoteKeyOptional.
 	CommitmentTweak bool `long:"committweak" description:"force node to not advertise the new commitment format"`
-
-	// Anchors should be set if we want to support opening or accepting
-	// channels having the anchor commitment type.
-	Anchors bool `long:"anchors" description:"EXPERIMENTAL: enable experimental support for anchor commitments, won't work with watchtowers"`
 }
 
 // LegacyOnion returns true if the old legacy onion format should be used when
 // we're an intermediate or final hop. This controls if we set the
 // TLVOnionPayloadOptional bit or not.
-func (l *ProtocolOptions) LegacyOnion() bool {
+func (l *LegacyProtocol) LegacyOnion() bool {
 	return l.LegacyOnionFormat
 }
 
 // NoStaticRemoteKey returns true if the old commitment format with a tweaked
 // remote key should be used for new funded channels.
-func (l *ProtocolOptions) NoStaticRemoteKey() bool {
+func (l *LegacyProtocol) NoStaticRemoteKey() bool {
 	return l.CommitmentTweak
 }
-
-// AnchorCommitments returns true if support for the anchor commitment type
-// should be signaled.
-func (l *ProtocolOptions) AnchorCommitments() bool {
-	return l.Anchors
-}

lntest/itest/lnd_multi-hop-payments.go

@@ -48,7 +48,7 @@ func testMultiHopPayments(net *lntest.NetworkHarness, t *harnessTest) {
 	//
 	// First, we'll create Dave and establish a channel to Alice. Dave will
 	// be running an older node that requires the legacy onion payload.
-	daveArgs := []string{"--protocol.legacyonion"}
+	daveArgs := []string{"--protocol.legacy.onion"}
 	dave, err := net.NewNode("Dave", daveArgs)
 	if err != nil {
 		t.Fatalf("unable to create new nodes: %v", err)

lntest/itest/lnd_test.go

@@ -1178,7 +1178,7 @@ func (c commitType) String() string {
 func (c commitType) Args() []string {
 	switch c {
 	case commitTypeLegacy:
-		return []string{"--protocol.committweak"}
+		return []string{"--protocol.legacy.committweak"}
 	case commitTypeTweakless:
 		return []string{}
 	case commitTypeAnchors: