fix

Author: mohamedawnallah

wallet/multisig.go

@@ -7,6 +7,7 @@ package wallet
 
 import (
 	"errors"
+	"fmt"
 
 	"github.com/btcsuite/btcd/btcutil"
 	"github.com/btcsuite/btcd/txscript"
@@ -52,18 +53,29 @@ func (w *Wallet) MakeMultiSigScript(addrs []btcutil.Address, nRequired int) ([]b
 				}
 				addrmgrNs = dbtx.ReadBucket(waddrmgrNamespaceKey)
 			}
+
 			addrInfo, err := w.Manager.Address(addrmgrNs, addr)
 			if err != nil {
 				return nil, err
 			}
-			serializedPubKey := addrInfo.(waddrmgr.ManagedPubKeyAddress).
-				PubKey().SerializeCompressed()
+
+			mpka, ok := addrInfo.(waddrmgr.ManagedPubKeyAddress)
+			if !ok {
+				err := fmt.Errorf("managed address type for "+
+					"%v is `%T` but want "+
+					"waddrmgr.ManagedPubKeyAddress", addr,
+					addrInfo)
+				return nil, err
+			}
+
+			serializedPubKey := mpka.PubKey().SerializeCompressed()
 
 			pubKeyAddr, err := btcutil.NewAddressPubKey(
 				serializedPubKey, w.chainParams)
 			if err != nil {
 				return nil, err
 			}
+
 			pubKeys[i] = pubKeyAddr
 		}
 	}