Add tests for pdu encoding

pdu/pdu_test.go

@@ -0,0 +1,67 @@
+package pdu
+
+import "testing"
+
+func TestEncodeReturnsByteSliceOfLength16(t *testing.T) {
+	p := &PDU_HEADER{
+		command_length:  1,
+		command_id:      1,
+		command_status:  1,
+		sequence_number: 1,
+	}
+	result := p.Encode()
+	if len(result) != 16 {
+		t.Errorf("Expected byte slice of length 16, got %d", len(result))
+	}
+}
+
+func TestEncodeHandlesZeroValues(t *testing.T) {
+	p := &PDU_HEADER{
+		command_length:  0,
+		command_id:      0,
+		command_status:  0,
+		sequence_number: 0,
+	}
+	result := p.Encode()
+	expected := make([]byte, 16)
+	for i, v := range result {
+		if v != expected[i] {
+			t.Errorf("Expected byte slice with zero values, got %v", result)
+			break
+		}
+	}
+}
+
+func TestEncodeEncodesProperly(t *testing.T) {
+	p := &PDU_HEADER{
+		command_length:  1,
+		command_id:      2,
+		command_status:  3,
+		sequence_number: 4,
+	}
+	result := p.Encode()
+	expected := []byte{0, 0, 0, 1, 0, 0, 0, 2, 0, 0, 0, 3, 0, 0, 0, 4}
+	for i, v := range result {
+		if v != expected[i] {
+			t.Errorf("Expected byte slice with values %v, got %v", expected, result)
+			break
+		}
+	}
+}
+
+func TestEncodeEncodesProperlyComplex(t *testing.T) {
+	p := &PDU_HEADER{
+		command_length:  13426724,
+		command_id:      254352,
+		command_status:  35634264,
+		sequence_number: 476543523,
+	}
+	result := p.Encode()
+	expected := []byte{0, 204, 224, 36, 0, 3, 225, 144, 2, 31, 188, 88, 28, 103, 122, 35}
+	for i, v := range result {
+		if v != expected[i] {
+			t.Errorf("Expected byte slice with values %v, got %v", expected, result)
+			break
+		}
+	}
+}