lnd: removing activeNetParams global, passed around instead via configs

This commit removes the activeNetParams global in chainparams.go. This
is necessary to isolate code from the lnd package so we can import it
for use in tests, other projects, etc.

config.go

@@ -274,6 +274,9 @@ type Config struct {
 	// network. This path will hold the files related to each different
 	// network.
 	networkDir string
+
+	// ActiveNetParams contains parameters of the target chain.
+	ActiveNetParams bitcoinNetParams
 }
 
 // DefaultConfig returns all default values for the Config struct.
@@ -380,6 +383,7 @@ func DefaultConfig() Config {
 		LogWriter:               build.NewRotatingLogWriter(),
 		DB:                      lncfg.DefaultDB(),
 		registeredChains:        newChainRegistry(),
+		ActiveNetParams:         bitcoinTestNetParams,
 	}
 }
 
@@ -736,12 +740,12 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 		// throughout the codebase we required chaincfg.Params. So as a
 		// temporary hack, we'll mutate the default net params for
 		// bitcoin with the litecoin specific information.
-		applyLitecoinParams(&activeNetParams, &ltcParams)
+		applyLitecoinParams(&cfg.ActiveNetParams, &ltcParams)
 
 		switch cfg.Litecoin.Node {
 		case "ltcd":
 			err := parseRPCParams(cfg.Litecoin, cfg.LtcdMode,
-				litecoinChain, funcName)
+				litecoinChain, funcName, cfg.ActiveNetParams)
 			if err != nil {
 				err := fmt.Errorf("unable to load RPC "+
 					"credentials for ltcd: %v", err)
@@ -753,7 +757,7 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 					"support simnet", funcName)
 			}
 			err := parseRPCParams(cfg.Litecoin, cfg.LitecoindMode,
-				litecoinChain, funcName)
+				litecoinChain, funcName, cfg.ActiveNetParams)
 			if err != nil {
 				err := fmt.Errorf("unable to load RPC "+
 					"credentials for litecoind: %v", err)
@@ -781,19 +785,19 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 		numNets := 0
 		if cfg.Bitcoin.MainNet {
 			numNets++
-			activeNetParams = bitcoinMainNetParams
+			cfg.ActiveNetParams = bitcoinMainNetParams
 		}
 		if cfg.Bitcoin.TestNet3 {
 			numNets++
-			activeNetParams = bitcoinTestNetParams
+			cfg.ActiveNetParams = bitcoinTestNetParams
 		}
 		if cfg.Bitcoin.RegTest {
 			numNets++
-			activeNetParams = bitcoinRegTestNetParams
+			cfg.ActiveNetParams = bitcoinRegTestNetParams
 		}
 		if cfg.Bitcoin.SimNet {
 			numNets++
-			activeNetParams = bitcoinSimNetParams
+			cfg.ActiveNetParams = bitcoinSimNetParams
 		}
 		if numNets > 1 {
 			str := "%s: The mainnet, testnet, regtest, and " +
@@ -822,6 +826,7 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 		case "btcd":
 			err := parseRPCParams(
 				cfg.Bitcoin, cfg.BtcdMode, bitcoinChain, funcName,
+				cfg.ActiveNetParams,
 			)
 			if err != nil {
 				err := fmt.Errorf("unable to load RPC "+
@@ -836,6 +841,7 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 
 			err := parseRPCParams(
 				cfg.Bitcoin, cfg.BitcoindMode, bitcoinChain, funcName,
+				cfg.ActiveNetParams,
 			)
 			if err != nil {
 				err := fmt.Errorf("unable to load RPC "+
@@ -913,7 +919,7 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 	cfg.networkDir = filepath.Join(
 		cfg.DataDir, defaultChainSubDirname,
 		cfg.registeredChains.PrimaryChain().String(),
-		normalizeNetwork(activeNetParams.Name),
+		normalizeNetwork(cfg.ActiveNetParams.Name),
 	)
 
 	// If a custom macaroon directory wasn't specified and the data
@@ -947,7 +953,7 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 	// per network in the same fashion as the data directory.
 	cfg.LogDir = filepath.Join(cfg.LogDir,
 		cfg.registeredChains.PrimaryChain().String(),
-		normalizeNetwork(activeNetParams.Name))
+		normalizeNetwork(cfg.ActiveNetParams.Name))
 
 	// A log writer must be passed in, otherwise we can't function and would
 	// run into a panic later on.
@@ -1135,11 +1141,11 @@ func ValidateConfig(cfg Config, usageMessage string) (*Config, error) {
 func (c *Config) localDatabaseDir() string {
 	return filepath.Join(c.DataDir,
 		defaultGraphSubDirname,
-		normalizeNetwork(activeNetParams.Name))
+		normalizeNetwork(c.ActiveNetParams.Name))
 }
 
 func (c *Config) networkName() string {
-	return normalizeNetwork(activeNetParams.Name)
+	return normalizeNetwork(c.ActiveNetParams.Name)
 }
 
 // CleanAndExpandPath expands environment variables and leading ~ in the
@@ -1169,7 +1175,7 @@ func CleanAndExpandPath(path string) string {
 }
 
 func parseRPCParams(cConfig *lncfg.Chain, nodeConfig interface{}, net chainCode,
-	funcName string) error { // nolint:unparam
+	funcName string, netParams bitcoinNetParams) error { // nolint:unparam
 
 	// First, we'll check our node config to make sure the RPC parameters
 	// were set correctly. We'll also determine the path to the conf file
@@ -1279,7 +1285,7 @@ func parseRPCParams(cConfig *lncfg.Chain, nodeConfig interface{}, net chainCode,
 	case "bitcoind", "litecoind":
 		nConf := nodeConfig.(*lncfg.Bitcoind)
 		rpcUser, rpcPass, zmqBlockHost, zmqTxHost, err :=
-			extractBitcoindRPCParams(confFile)
+			extractBitcoindRPCParams(netParams.Params.Name, confFile)
 		if err != nil {
 			return fmt.Errorf("unable to extract RPC credentials:"+
 				" %v, cannot start w/o RPC connection",
@@ -1339,13 +1345,13 @@ func extractBtcdRPCParams(btcdConfigPath string) (string, string, error) {
 	return string(userSubmatches[1]), string(passSubmatches[1]), nil
 }
 
-// extractBitcoindParams attempts to extract the RPC credentials for an
+// extractBitcoindRPCParams attempts to extract the RPC credentials for an
 // existing bitcoind node instance. The passed path is expected to be the
 // location of bitcoind's bitcoin.conf on the target system. The routine looks
 // for a cookie first, optionally following the datadir configuration option in
 // the bitcoin.conf. If it doesn't find one, it looks for rpcuser/rpcpassword.
-func extractBitcoindRPCParams(bitcoindConfigPath string) (string, string, string,
-	string, error) {
+func extractBitcoindRPCParams(networkName string,
+	bitcoindConfigPath string) (string, string, string, string, error) {
 
 	// First, we'll open up the bitcoind configuration file found at the
 	// target destination.
@@ -1403,7 +1409,7 @@ func extractBitcoindRPCParams(bitcoindConfigPath string) (string, string, string
 	}
 
 	chainDir := "/"
-	switch activeNetParams.Params.Name {
+	switch networkName {
 	case "testnet3":
 		chainDir = "/testnet3/"
 	case "testnet4":