1 files changed, 44 insertions, 0 deletions
diff --git a/dhcpv4/option_subnet_mask_test.go b/dhcpv4/option_subnet_mask_test.go
new file mode 100644
index 0000000..4cb8819
--- /dev/null
+++ b/dhcpv4/option_subnet_mask_test.go
@@ -0,0 +1,44 @@
+package dhcpv4
+
+import (
+	"net"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestOptSubnetMaskInterfaceMethods(t *testing.T) {
+	mask := net.IPMask{255, 255, 255, 0}
+	o := OptSubnetMask{SubnetMask: mask}
+
+	require.Equal(t, OptionSubnetMask, o.Code(), "Code")
+
+	expectedBytes := []byte{1, 4, 255, 255, 255, 0}
+	require.Equal(t, expectedBytes, o.ToBytes(), "ToBytes")
+
+	require.Equal(t, 4, o.Length(), "Length")
+
+	require.Equal(t, "Subnet Mask -> ffffff00", o.String(), "String")
+}
+
+func TestParseOptSubnetMask(t *testing.T) {
+	var (
+		o   *OptSubnetMask
+		err error
+	)
+	o, err = ParseOptSubnetMask([]byte{})
+	require.Error(t, err, "empty byte stream")
+
+	o, err = ParseOptSubnetMask([]byte{1, 4, 255})
+	require.Error(t, err, "short byte stream")
+
+	o, err = ParseOptSubnetMask([]byte{1, 3, 255, 255, 255, 0})
+	require.Error(t, err, "wrong IP length")
+
+	o, err = ParseOptSubnetMask([]byte{2, 4, 255, 255, 255})
+	require.Error(t, err, "wrong option code")
+
+	o, err = ParseOptSubnetMask([]byte{1, 4, 255, 255, 255, 0})
+	require.NoError(t, err)
+	require.Equal(t, net.IPMask{255, 255, 255, 0}, o.SubnetMask)
+}