simplified paxos added more tests

lib/paxos.ex

@@ -1,51 +1,3 @@
-
-
-defmodule Ballot do
-
-  def init(name, number \\ 0) do
-    {name, number}
-  end
-
-  def inc(b, name \\ nil) do
-    {old_name, number} = b
-
-    {
-      if name == nil do
-        old_name
-      else
-        name
-      end,
-
-      number + 1
-    }
-  end
-
-  
-  defp lexicographical_compare(a, b) do
-    cond do
-      a == b -> 0
-      a > b -> 1
-      true -> -1
-    end
-  end
-
-
-  defp diff({name1, number1}, {name2, number2}) do
-    diff = number1 - number2
-    if diff == 0 do
-      lexicographical_compare(name1, name2)
-    else
-      diff
-    end
-  end
-
-  def compare(b1, operator, b2) do
-    operator.(diff(b1, b2), 0)
-  end
-
-end
-
-
 #
 #
 # Possible actions
@@ -76,7 +28,6 @@ defmodule Paxos do
       processes: processes,
       leader: nil,
       instmap: %{},
-      other_values: %{},
       decided: %{}
     }
 
@@ -90,6 +41,7 @@ defmodule Paxos do
       instmap =
         Map.put(state.instmap, inst, %{
           value: value,
+          other_value: nil,
           ballot: Ballot.init(state.name, 0),
           aborted: false,
           ballot_value: nil,
@@ -172,8 +124,6 @@ defmodule Paxos do
           end
 
         {:rb_deliver, proc, {:other_propose, inst, value}} ->
-          state = %{state | other_values: Map.put(state.other_values, inst, value)}
-
           cond do
             has_finished(state, inst, true) ->
               EagerReliableBroadcast.broadcast(
@@ -184,6 +134,7 @@ defmodule Paxos do
 
             true -> 
               state = has_or_create(state, inst)
+              state = set_instmap(state, inst, fn map -> %{map | other_value: value} end)
               prepare(state, inst)
           end
 
@@ -399,7 +350,7 @@ defmodule Paxos do
       state.instmap[inst] == nil ->
         state
 
-      state.instmap[inst].value == nil and state.other_values[inst] == nil ->
+      state.instmap[inst].value == nil and state.instmap[inst].other_value == nil ->
         state
 
       state.instmap[inst] != nil and state.instmap[inst].has_sent_prepare ->
@@ -449,7 +400,7 @@ defmodule Paxos do
       a_val =
         if a_val == nil do
           if state.instmap[inst].value == nil do
-            state.other_values[inst]
+            state.instmap[inst].other_value
           else
             state.instmap[inst].value
           end
@@ -556,3 +507,47 @@ defmodule Paxos do
   end
 end
 
+defmodule Ballot do
+
+  def init(name, number \\ 0) do
+    {name, number}
+  end
+
+  def inc(b, name \\ nil) do
+    {old_name, number} = b
+
+    {
+      if name == nil do
+        old_name
+      else
+        name
+      end,
+
+      number + 1
+    }
+  end
+
+  
+  defp lexicographical_compare(a, b) do
+    cond do
+      a == b -> 0
+      a > b -> 1
+      true -> -1
+    end
+  end
+
+
+  defp diff({name1, number1}, {name2, number2}) do
+    diff = number1 - number2
+    if diff == 0 do
+      lexicographical_compare(name1, name2)
+    else
+      diff
+    end
+  end
+
+  def compare(b1, operator, b2) do
+    operator.(diff(b1, b2), 0)
+  end
+
+end