testing: Adding MockEmptyAcknowledgement to testing library

modules/core/04-channel/keeper/packet_test.go

@@ -551,7 +551,7 @@ func (suite *KeeperTestSuite) TestWriteAcknowledgement() {
 			func() {
 				suite.coordinator.Setup(path)
 				packet = types.NewPacket(ibctesting.MockPacketData, 1, path.EndpointA.ChannelConfig.PortID, path.EndpointA.ChannelID, path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID, timeoutHeight, disabledTimeoutTimestamp)
-				ack = types.NewResultAcknowledgement(nil)
+				ack = ibcmock.NewMockEmptyAcknowledgement()
 				channelCap = suite.chainB.GetChannelCapability(path.EndpointB.ChannelConfig.PortID, path.EndpointB.ChannelID)
 			},
 			false,

testing/mock/ack.go

@@ -0,0 +1,23 @@
+package mock
+
+// MockEmptyAcknowledgement implements the exported.Acknowledgement interface and always returns an empty byte string as Response
+type MockEmptyAcknowledgement struct {
+	Response []byte
+}
+
+// NewMockEmptyAcknowledgement returns a new instance of MockEmptyAcknowledgement
+func NewMockEmptyAcknowledgement() MockEmptyAcknowledgement {
+	return MockEmptyAcknowledgement{
+		Response: []byte{},
+	}
+}
+
+// Success implements the Acknowledgement interface
+func (ack MockEmptyAcknowledgement) Success() bool {
+	return true
+}
+
+// Acknowledgement implements the Acknowledgement interface
+func (ack MockEmptyAcknowledgement) Acknowledgement() []byte {
+	return []byte{}
+}