add basic AckHandler

ackhandler/ack_handler_test.go

@@ -0,0 +1,84 @@
+package ackhandler
+
+import (
+	"github.com/lucas-clemente/quic-go/protocol"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("AckHandler", func() {
+	It("Returns no NACK ranges for continously received packets", func() {
+		ackHandler, _ := NewAckHandler()
+		for i := 0; i < 100; i++ {
+			ackHandler.HandlePacket(protocol.PacketNumber(i))
+		}
+		Expect(ackHandler.LargestObserved).To(Equal(protocol.PacketNumber(99)))
+		Expect(len(ackHandler.GetNackRanges())).To(Equal(0))
+	})
+
+	It("handles a single lost package", func() {
+		ackHandler, _ := NewAckHandler()
+		for i := 0; i < 10; i++ {
+			if i == 5 {
+				continue
+			}
+			ackHandler.HandlePacket(protocol.PacketNumber(i))
+		}
+		Expect(ackHandler.LargestObserved).To(Equal(protocol.PacketNumber(9)))
+		nackRanges := ackHandler.GetNackRanges()
+		Expect(len(nackRanges)).To(Equal(1))
+		Expect(nackRanges[0].FirstPacketNumber).To(Equal(protocol.PacketNumber(5)))
+		Expect(nackRanges[0].Length).To(Equal(uint8(1)))
+	})
+
+	It("handles two consecutive lost packages", func() {
+		ackHandler, _ := NewAckHandler()
+		for i := 0; i < 10; i++ {
+			if i == 5 || i == 6 {
+				continue
+			}
+			ackHandler.HandlePacket(protocol.PacketNumber(i))
+		}
+		Expect(ackHandler.LargestObserved).To(Equal(protocol.PacketNumber(9)))
+		nackRanges := ackHandler.GetNackRanges()
+		Expect(len(nackRanges)).To(Equal(1))
+		Expect(nackRanges[0].FirstPacketNumber).To(Equal(protocol.PacketNumber(5)))
+		Expect(nackRanges[0].Length).To(Equal(uint8(2)))
+	})
+
+	It("handles two non-consecutively lost packages", func() {
+		ackHandler, _ := NewAckHandler()
+		for i := 0; i < 10; i++ {
+			if i == 3 || i == 7 {
+				continue
+			}
+			ackHandler.HandlePacket(protocol.PacketNumber(i))
+		}
+		Expect(ackHandler.LargestObserved).To(Equal(protocol.PacketNumber(9)))
+		nackRanges := ackHandler.GetNackRanges()
+		Expect(len(nackRanges)).To(Equal(2))
+		Expect(nackRanges[0].FirstPacketNumber).To(Equal(protocol.PacketNumber(3)))
+		Expect(nackRanges[0].Length).To(Equal(uint8(1)))
+		Expect(nackRanges[1].FirstPacketNumber).To(Equal(protocol.PacketNumber(7)))
+		Expect(nackRanges[1].Length).To(Equal(uint8(1)))
+	})
+
+	It("handles two sequences of lost packages", func() {
+		ackHandler, _ := NewAckHandler()
+		for i := 0; i < 10; i++ {
+			if i == 2 || i == 3 || i == 4 || i == 7 || i == 8 {
+				continue
+			}
+			ackHandler.HandlePacket(protocol.PacketNumber(i))
+		}
+		Expect(ackHandler.LargestObserved).To(Equal(protocol.PacketNumber(9)))
+		nackRanges := ackHandler.GetNackRanges()
+		Expect(len(nackRanges)).To(Equal(2))
+		Expect(nackRanges[0].FirstPacketNumber).To(Equal(protocol.PacketNumber(2)))
+		Expect(nackRanges[0].Length).To(Equal(uint8(3)))
+		Expect(nackRanges[1].FirstPacketNumber).To(Equal(protocol.PacketNumber(7)))
+		Expect(nackRanges[1].Length).To(Equal(uint8(2)))
+	})
+
+})