From d67ba999a512e74670550187da00232d17a64142 Mon Sep 17 00:00:00 2001
From: Tim Makarios <tjm1983@gmail.com>
Date: Wed, 19 Feb 2014 13:39:30 +1300
Subject: [PATCH] Helper for arbitrary valid parameters for addNode

---
 Test/ValueSimplex.hs | 14 ++++++++++++++
 rootstock.cabal      |  2 ++
 2 files changed, 16 insertions(+)

diff --git a/Test/ValueSimplex.hs b/Test/ValueSimplex.hs
index e13dcad..b022c4d 100644
--- a/Test/ValueSimplex.hs
+++ b/Test/ValueSimplex.hs
@@ -12,6 +12,7 @@ import Data.Maybe (fromJust)
 import Data.Set (Set)
 import qualified Data.Set as Set
 import Numeric.Matrix (MatrixElement)
+import System.Random (Random)
 import Test.QuickCheck
 import Test.QuickCheck.All
 import Test.Set
@@ -508,6 +509,19 @@ prop_totalValue_correct = approx_Double_exact_Rational $ \eq vs ->
   totalValue vs x 
   `eq` Set.foldr ((+) . (\y -> nodeValue vs y * price vs y x)) 0 (nodes vs)
 
+withArbitraryAddNodeParameters ::
+  ( Arbitrary a, Ord a, Show a
+  , Arbitrary b, Random b, Ord b, Fractional b, Show b
+  , Testable p
+  )
+  => ValueSimplex a b -> (a -> b -> a -> b -> p) -> Property
+withArbitraryAddNodeParameters vs test =
+  property $ \x ->
+  Set.notMember x (nodes vs) ==>
+  property $ \(Positive q) ->
+  withArbitraryNode vs $ \y ->
+  forAll (choose (0, totalValue vs y / q)) $ test x q y
+
 --------------------------------------------------------------------------------
 
 allValueSimplexTests :: IO Bool
diff --git a/rootstock.cabal b/rootstock.cabal
index 783462f..083348c 100644
--- a/rootstock.cabal
+++ b/rootstock.cabal
@@ -44,6 +44,7 @@ Test-Suite rootstock-tests
     , bed-and-breakfast >=0.4.2 && <0.5
     , containers >=0.4 && <0.5
     , QuickCheck >=2.6
+    , random >= 1.0
     , type-level-natural-number >=1.0
   default-language: Haskell2010
 
@@ -57,6 +58,7 @@ Test-Suite longrun-test
     , containers >=0.4 && <0.5
     , persistent-template >=1.2
     , QuickCheck >=2.6
+    , random >= 1.0
     , text >=0.11
     , type-level-natural-number >=1.0
   default-language: Haskell2010
-- 
2.11.4.GIT