buck's review

client/asset/dcr/dcr.go

@@ -348,9 +348,7 @@ func (d *Driver) DecodeCoinID(coinID []byte) (string, error) {
 	return fmt.Sprintf("%v:%d", txid, vout), err
 }
 
-// Info returns basic information about the wallet and asset. WARNING: An
-// ExchangeWallet instance may have different DefaultFeeRate set, so use
-// (*ExchangeWallet).Info when possible.
+// Info returns basic information about the wallet and asset.
 func (d *Driver) Info() *asset.WalletInfo {
 	return WalletInfo
 }
@@ -430,23 +428,23 @@ func NewWallet(cfg *asset.WalletConfig, logger dex.Logger, network dex.Network)
 	}
 
 	// Set dcr.wallet using either the default rpcWallet or a custom wallet.
-	if customWalletConstructor == nil {
-		dcr.wallet, err = newRPCWallet(walletCfg, chainParams, logger)
+	if makeCustomWallet, ok := customWalletConstructors[cfg.Type]; ok {
+		dcr.wallet, err = makeCustomWallet(cfg, chainParams, logger)
 		if err != nil {
-			return nil, err
+			return nil, fmt.Errorf("custom wallet setup error: %v", err)
 		}
 	} else {
-		dcr.wallet, err = customWalletConstructor(walletCfg, chainParams, logger)
+		dcr.wallet, err = newRPCWallet(walletCfg, chainParams, logger)
 		if err != nil {
-			return nil, fmt.Errorf("custom wallet setup error: %v", err)
+			return nil, err
 		}
 	}
 
 	return dcr, nil
 }
 
-// unconnectedWallet returns an ExchangeWallet without a node. The node should
-// be set before use.
+// unconnectedWallet returns an ExchangeWallet without a base wallet. The wallet
+// should be set before use.
 func unconnectedWallet(cfg *asset.WalletConfig, dcrCfg *Config, chainParams *chaincfg.Params, logger dex.Logger) (*ExchangeWallet, error) {
 	// If set in the user config, the fallback fee will be in units of DCR/kB.
 	// Convert to atoms/B.

client/asset/dcr/rpcwallet.go

@@ -250,15 +250,15 @@ func (w *rpcWallet) Disconnected() bool {
 	return w.rpcConnector.Disconnected()
 }
 
-// Disconnected returns true if the rpc client is not connected.
+// Network returns the network of the connected wallet.
 // Part of the Wallet interface.
 func (w *rpcWallet) Network(ctx context.Context) (wire.CurrencyNet, error) {
 	net, err := w.rpcClient.GetCurrentNet(ctx)
 	return net, translateRPCCancelErr(err)
 }
 
-// NotifyOnTipChange registers a callback function that the should be invoked
-// when the wallet sees new mainchain blocks. The return value indicates if this
+// NotifyOnTipChange registers a callback function that should be invoked when
+// the wallet sees new mainchain blocks. The return value indicates if this
 // notification can be provided.
 // Part of the Wallet interface.
 func (w *rpcWallet) NotifyOnTipChange(ctx context.Context, cb TipChangeCallback) bool {
@@ -525,7 +525,7 @@ func (w *rpcWallet) AddressPrivKey(ctx context.Context, address stdaddr.Address)
 type anylist []interface{}
 
 // rpcClientRawRequest is used to marshal parameters and send requests to the
-// RPC server via rpcClient.RawRequest. If `thing` is non-nil, the resul will
+// RPC server via rpcClient.RawRequest. If `thing` is non-nil, the result will
 // be marshaled into `thing`.
 func (w *rpcWallet) rpcClientRawRequest(ctx context.Context, method string, args anylist, thing interface{}) error {
 	params := make([]json.RawMessage, 0, len(args))

client/asset/dcr/wallet.go

@@ -21,31 +21,36 @@ import (
 
 // WalletConstructor defines a function that can be invoked to create a custom
 // implementation of the Wallet interface.
-type WalletConstructor func(cfg *Config, chainParams *chaincfg.Params, logger dex.Logger) (Wallet, error)
+type WalletConstructor func(cfg *asset.WalletConfig, chainParams *chaincfg.Params, logger dex.Logger) (Wallet, error)
 
-// customWalletConstructor is a function that can be invoked when setting up
-// the ExchangeWallet to set up a custom implementation of the Wallet interface
-// which will be used instead of the default rpcWallet implementation.
-var customWalletConstructor WalletConstructor
+// customWalletConstructors are functions for setting up custom implementations
+// of the Wallet interface that may be used by the ExchangeWallet instead of the
+// default rpcWallet implementation.
+var customWalletConstructors map[string]WalletConstructor
 
-// RegisterCustomWallet specifies the function that should be used in creating
-// a wallet implementation that the ExchangeWallet will use in place of the
-// default rpcWallet implementation. External consumers can use this function
-// to provide alternative Wallet implementations, and must do so before an
-// ExchangeWallet instance is created.
+// RegisterCustomWallet registers a function that should be used in creating a
+// Wallet implementation that the ExchangeWallet of the specified type will use
+// in place of the default rpcWallet implementation. External consumers can use
+// this function to provide alternative Wallet implementations, and must do so
+// before attempting to create an ExchangeWallet instance of this type.
 func RegisterCustomWallet(constructor WalletConstructor, def *asset.WalletDefinition) error {
 	for _, availableWallets := range WalletInfo.AvailableWallets {
 		if def.Type == availableWallets.Type {
 			return fmt.Errorf("already support %q wallets", def.Type)
 		}
 	}
-	customWalletConstructor = constructor
+	customWalletConstructors[def.Type] = constructor
 	WalletInfo.AvailableWallets = append(WalletInfo.AvailableWallets, def)
 	return nil
 }
 
 type TipChangeCallback func(*chainhash.Hash, int64, error)
 
+// Wallet defines methods that the ExchangeWallet uses for communicating with
+// a Decred wallet and blockchain.
+// TODO: Where possible, replace walletjson and chainjson return types with
+// other types that define fewer fields e.g. *chainjson.TxRawResult with
+// *wire.MsgTx.
 type Wallet interface {
 	// Connect establishes a connection to the wallet.
 	Connect(ctx context.Context) error

client/asset/driver.go

@@ -133,8 +133,6 @@ func Assets() map[uint32]RegisteredAsset {
 }
 
 // Info returns the WalletInfo for the specified asset, if supported.
-// WARNING: An ExchangeWallet instance may have different config values set,
-// so use (*ExchangeWallet).Info when possible.
 func Info(assetID uint32) (*WalletInfo, error) {
 	driversMtx.RLock()
 	drv, ok := drivers[assetID]