Function TestTagExtension

encdec_test.go:757–863

Test TagExtension

(t *testing.T)

// Test TagExtension
func TestTagExtension(t *testing.T) {
	// Normal tag cannot exceed 0xff and there is no automatic
	// conversion of the high-value tags into extended.
	m1 := NewResponse(DefaultVersion, StatusOk, 0x12345678)
	m1.Operation.Add(MakeAttribute("attr", 0x100, Binary{1, 2, 3, 4, 5}))

	_, err := m1.EncodeBytes()
	assertErrorIs(t, err, "Tag 0x00000100 out of range")

	// Ensure extension tag encodes and decodes well
	m1 = NewResponse(DefaultVersion, StatusOk, 0x12345678)
	m1.Operation.Add(MakeAttribute("attr", TagExtension,
		Binary{1, 2, 3, 4, 5}))

	data, err := m1.EncodeBytes()
	assertNoError(t, err)

	m2 := Message{}
	err = m2.DecodeBytes(data)
	assertNoError(t, err)

	if !m1.Equal(m2) {
		t.Errorf("Message is not the same after encoding and decoding")
	}

	// Extension tag requires Binary payload
	m1 = NewResponse(DefaultVersion, StatusOk, 0x12345678)
	m1.Operation.Add(MakeAttribute("attr", TagExtension,
		String("hello")))

	_, err = m1.EncodeBytes()
	assertErrorIs(t, err, "Tag extension: Binary value required, String present")

	// Extension tag requires at least 4 bytes of payload
	m1 = NewResponse(DefaultVersion, StatusOk, 0x12345678)
	m1.Operation.Add(MakeAttribute("attr", TagExtension,
		Binary{1, 2, 3}))

	_, err = m1.EncodeBytes()
	assertErrorIs(t, err, "Extension tag truncated")

	// Extension tag can't exceed 0x7fffffff, check that encoder
	// validates it.
	m1 = NewResponse(DefaultVersion, StatusOk, 0x12345678)
	m1.Operation.Add(MakeAttribute("attr", TagExtension,
		Binary{0x80, 1, 2, 3, 4, 5}))

	_, err = m1.EncodeBytes()
	assertErrorIs(t, err, "Extension tag 0x80010203 out of range")

	// Now prepare to decoder tests
	var d []byte
	var m = &Message{}

	hdr := []byte{
		0x01, 0x01, // IPP version
		0x00, 0x02, // Print-Job operation
		0x01, 0x02, 0x03, 0x04, // Request ID