htlcswitch.test: add server error channel to concurrent access panic

This commit where added as a measure to avoid the panic during several
server simultanoius fault. The panic happened becuase *t.Testing
structure is not concurrent safe.

htlcswitch/mock.go

@@ -11,8 +11,6 @@ import (
 
 	"bytes"
 
-	"testing"
-
 	"github.com/btcsuite/fastsha256"
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lnd/chainntnfs"
@@ -26,17 +24,16 @@ import (
 )
 
 type mockServer struct {
-	sync.Mutex
-
 	started  int32
 	shutdown int32
 	wg       sync.WaitGroup
-	quit     chan bool
+	quit     chan struct{}
 
-	t        *testing.T
 	name     string
 	messages chan lnwire.Message
 
+	errChan chan error
+
 	id         [33]byte
 	htlcSwitch *Switch
 
@@ -46,17 +43,17 @@ type mockServer struct {
 
 var _ Peer = (*mockServer)(nil)
 
-func newMockServer(t *testing.T, name string) *mockServer {
+func newMockServer(name string, errChan chan error) *mockServer {
 	var id [33]byte
 	h := sha256.Sum256([]byte(name))
 	copy(id[:], h[:])
 
 	return &mockServer{
-		t:                t,
+		errChan:          errChan,
 		id:               id,
 		name:             name,
 		messages:         make(chan lnwire.Message, 3000),
-		quit:             make(chan bool),
+		quit:             make(chan struct{}),
 		registry:         newMockRegistry(),
 		htlcSwitch:       New(Config{}),
 		interceptorFuncs: make([]messageInterceptor, 0),
@@ -94,9 +91,7 @@ func (s *mockServer) Start() error {
 				}
 
 				if err := s.readHandler(msg); err != nil {
-					s.Lock()
-					defer s.Unlock()
-					s.t.Fatalf("%v server error: %v", s.name, err)
+					s.errChan <- errors.Errorf("%v server error: %v", s.name, err)
 				}
 			case <-s.quit:
 				return
@@ -329,7 +324,8 @@ func (s *mockServer) Disconnect(reason error) {
 	fmt.Printf("server %v disconnected due to %v\n", s.name, reason)
 
 	s.Stop()
-	s.t.Fatalf("server %v was disconnected", s.name)
+	s.errChan <- errors.Errorf("server %v was disconnected: %v", s.name,
+		reason)
 }
 
 func (s *mockServer) WipeChannel(*lnwallet.LightningChannel) error {