Add a channel abstraction to use for networking

1 files changed, 67 insertions, 13 deletions

diff --git a/spec/channel_spec.lua b/spec/channel_spec.lua
index 252c12e..d8dbb13 100644
--- a/spec/channel_spec.lua
+++ b/spec/channel_spec.lua
@@ -44,10 +44,18 @@ describe("channel module", function()
 			assert(#fc.buffer == 1)
 			assert(fc:recv() == "a")
 		end)
+		it("has a normal() function that does normal distribution", function()
+			local normal = channel.FaultyChannel.normal
+			for i = 1, 20 do
+				math.randomseed(i)
+				local res = normal(nil,1,0.1)
+				assert(res > 0.5 and res < 1.5)
+			end
+		end)
 		it("can pump() with no side effects if time has not changed", function()
 			channel.FaultyChannel.time = 0
 			local fc = channel.FaultyChannel({
-				loss_std = 0,
+				loss = 0,
 				avg_latency = 5
 			})
 			fc:send("a")
@@ -56,28 +64,27 @@ describe("channel module", function()
 			fc:pump()
 			assert(#fc.to_deliver == 1)
 			assert(#fc.buffer == 0)
-			
+			channel.FaultyChannel.time = 4
+			fc:pump()
+			fc:send("b")
+			assert(#fc.to_deliver == 2)
+			assert(#fc.buffer == 0)
+			channel.FaultyChannel.time = 6
+			fc:pump()
+			assert(#fc.to_deliver == 1)
+			assert(#fc.buffer == 1)
 		end)
-		--[[
 		it("can be configured to not drop messages", function()
 			channel.FaultyChannel.time = 0
 			local fc = channel.FaultyChannel({
 				avg_latency = 5,
-				loss_std = 0
+				loss = 0
 			})
 			local i = 100
 			for _ = 1,i do
 				fc:send("a")
 			end
-			print(#fc.to_deliver)
-			print(#fc.buffer)
-			fc:pump()
-			print(#fc.to_deliver)
-			print(#fc.buffer)
 			channel.FaultyChannel.time = 10
-			fc:pump()
-			print(#fc.to_deliver)
-			print(#fc.buffer)
 			local j = 0
 			while fc:poll() do
 				j = j + 1
@@ -100,6 +107,53 @@ describe("channel module", function()
 			end
 			assert(j < i)
 		end)
-		]]
+		it("should keep a queue of messages", function()
+			channel.FaultyChannel.time = 0
+			local fc = channel.FaultyChannel({
+				loss = 0,
+				avg_latency=0,
+				latency_std=0,
+			})
+			local i = 100
+			for j = 1, i do
+				fc:send(tostring(j))
+			end
+			channel.FaultyChannel.time = 1
+			fc:pump()
+			assert(#fc.to_deliver == 0)
+			assert(#fc.buffer == i)
+			for j = 1, i do
+				assert(tonumber(fc:recv()) == j)
+			end
+			assert(not fc:poll())
+		end)
+		it("should deliver messages with different latencies", function()
+			channel.FaultyChannel.time = 0
+			local fc = channel.FaultyChannel({
+				loss = 0,
+				avg_latency = 20,
+				latency_std = 5,
+			})
+			local i = 100
+			for j = 1, i do
+				fc:send(tostring(j))
+			end
+			local received = 0
+			local increment = 0.5
+			local last_received = nil
+			local found_out_of_order = false
+			while received < i do
+				while fc:poll() do
+					local recv = tonumber(fc:recv())
+					if last_received and last_received < recv then
+						found_out_of_order = true
+					end
+					last_received = recv
+					received = received + 1
+				end
+				channel.FaultyChannel.time = channel.FaultyChannel.time + increment
+			end
+			assert(found_out_of_order)
+		end)
 	end)
 end)