lnwallet: Move mocks to separate file and augment mockSigner.

To implement the BOLT 03 test vectors, a more powerful mockSigner is
required. The new version of mockSigner stores multiple keys and signs
the transaction outputs with the appropriate one.

lnwallet/channel_test.go

@@ -4,7 +4,6 @@ import (
 	"bytes"
 	"crypto/sha256"
 	"errors"
-	"fmt"
 	"io/ioutil"
 	"math/big"
 	"math/rand"
@@ -60,92 +59,6 @@ var (
 	numReqConfs = uint16(1)
 )
 
-type mockSigner struct {
-	key *btcec.PrivateKey
-}
-
-func (m *mockSigner) SignOutputRaw(tx *wire.MsgTx, signDesc *SignDescriptor) ([]byte, error) {
-	amt := signDesc.Output.Value
-	witnessScript := signDesc.WitnessScript
-	privKey := m.key
-
-	if !privKey.PubKey().IsEqual(signDesc.PubKey) {
-		return nil, fmt.Errorf("incorrect key passed")
-	}
-
-	switch {
-	case signDesc.SingleTweak != nil:
-		privKey = TweakPrivKey(privKey,
-			signDesc.SingleTweak)
-	case signDesc.DoubleTweak != nil:
-		privKey = DeriveRevocationPrivKey(privKey,
-			signDesc.DoubleTweak)
-	}
-
-	sig, err := txscript.RawTxInWitnessSignature(tx, signDesc.SigHashes,
-		signDesc.InputIndex, amt, witnessScript, signDesc.HashType,
-		privKey)
-	if err != nil {
-		return nil, err
-	}
-
-	return sig[:len(sig)-1], nil
-}
-func (m *mockSigner) ComputeInputScript(tx *wire.MsgTx, signDesc *SignDescriptor) (*InputScript, error) {
-
-	// TODO(roasbeef): expose tweaked signer from lnwallet so don't need to
-	// duplicate this code?
-
-	privKey := m.key
-
-	switch {
-	case signDesc.SingleTweak != nil:
-		privKey = TweakPrivKey(privKey,
-			signDesc.SingleTweak)
-	case signDesc.DoubleTweak != nil:
-		privKey = DeriveRevocationPrivKey(privKey,
-			signDesc.DoubleTweak)
-	}
-
-	witnessScript, err := txscript.WitnessSignature(tx, signDesc.SigHashes,
-		signDesc.InputIndex, signDesc.Output.Value, signDesc.Output.PkScript,
-		signDesc.HashType, privKey, true)
-	if err != nil {
-		return nil, err
-	}
-
-	return &InputScript{
-		Witness: witnessScript,
-	}, nil
-}
-
-type mockNotfier struct {
-}
-
-func (m *mockNotfier) RegisterConfirmationsNtfn(txid *chainhash.Hash, numConfs, heightHint uint32) (*chainntnfs.ConfirmationEvent, error) {
-	return nil, nil
-}
-
-func (m *mockNotfier) RegisterBlockEpochNtfn() (*chainntnfs.BlockEpochEvent, error) {
-	return nil, nil
-}
-
-func (m *mockNotfier) Start() error {
-	return nil
-}
-
-func (m *mockNotfier) Stop() error {
-	return nil
-}
-
-func (m *mockNotfier) RegisterSpendNtfn(outpoint *wire.OutPoint, heightHint uint32) (*chainntnfs.SpendEvent, error) {
-	return &chainntnfs.SpendEvent{
-		Spend: make(chan *chainntnfs.SpendDetail),
-		Cancel: func() {
-		},
-	}, nil
-}
-
 // mockSpendNotifier extends the mockNotifier so that spend notifications can be
 // triggered and delivered to subscribers.
 type mockSpendNotifier struct {
@@ -428,8 +341,8 @@ func createTestChannelsWithNotifier(revocationWindow int,
 		Db:                      dbBob,
 	}
 
-	aliceSigner := &mockSigner{aliceKeyPriv}
-	bobSigner := &mockSigner{bobKeyPriv}
+	aliceSigner := &mockSigner{privkeys: []*btcec.PrivateKey{aliceKeyPriv}}
+	bobSigner := &mockSigner{privkeys: []*btcec.PrivateKey{bobKeyPriv}}
 
 	channelAlice, err := NewLightningChannel(aliceSigner, notifier,
 		estimator, aliceChannelState)