diff --git a/codec_test.go b/codec_test.go
new file mode 100644
index 0000000..54b9e90
--- /dev/null
+++ b/codec_test.go
@@ -0,0 +1,66 @@
+package grpc
+
+import (
+	"context"
+	"go.unistack.org/micro/v3/codec"
+	gmetadata "google.golang.org/grpc/metadata"
+	"testing"
+)
+
+type mockStream struct {
+	msg any
+}
+
+func (m mockStream) Header() (gmetadata.MD, error) {
+	return nil, nil
+}
+
+func (m mockStream) Trailer() gmetadata.MD {
+	return nil
+}
+
+func (m mockStream) CloseSend() error {
+	return nil
+}
+
+func (m mockStream) Context() context.Context {
+	return nil
+}
+
+func (m *mockStream) SendMsg(msg any) error {
+	m.msg = msg
+	return nil
+}
+
+func (m *mockStream) RecvMsg(msg any) error {
+
+	c := msg.(*codec.Frame)
+	c.Data = m.msg.(*codec.Frame).Data
+
+	return nil
+}
+
+func Test_ReadWrap(t *testing.T) {
+
+	wp := wrapStream{
+		&mockStream{},
+	}
+
+	write, err := wp.Write([]byte("test_data"))
+	if err != nil {
+		t.Fatal(err)
+	}
+	if write != 9 {
+		t.Error("uncorrected number wrote bytes")
+	}
+
+	b := make([]byte, write)
+	read, err := wp.Read(b)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if read != 9 || string(b) != "test_data" {
+		t.Error("uncorrected number wrote bytes or data")
+	}
+}