From dac34f6ff5c46f11fe6c548b92a02ebf4f10d7e9 Mon Sep 17 00:00:00 2001
From: Yann Herklotz <ymherklotz@gmail.com>
Date: Thu, 10 Jan 2019 15:49:13 +0000
Subject: Rename files out of the module

---
 src/VeriFuzz/Graph/Random.hs | 58 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)
 create mode 100644 src/VeriFuzz/Graph/Random.hs

(limited to 'src/VeriFuzz/Graph/Random.hs')

diff --git a/src/VeriFuzz/Graph/Random.hs b/src/VeriFuzz/Graph/Random.hs
new file mode 100644
index 0000000..0514f6d
--- /dev/null
+++ b/src/VeriFuzz/Graph/Random.hs
@@ -0,0 +1,58 @@
+{-|
+Module      : VeriFuzz.Graph.Random
+Description : Random generation for DAG
+Copyright   : (c) 2018-2019, Yann Herklotz Grave
+License     : BSD-3
+Maintainer  : ymherklotz [at] gmail [dot] com
+Stability   : experimental
+Portability : POSIX
+
+Define the random generation for the directed acyclic graph.
+-}
+
+module VeriFuzz.Graph.Random where
+
+import           Data.Graph.Inductive              (Context, Graph, LEdge)
+import qualified Data.Graph.Inductive              as G
+import           Data.Graph.Inductive.PatriciaTree (Gr)
+import           Data.List                         (nub)
+import           Test.QuickCheck                   (Arbitrary, Gen)
+import qualified Test.QuickCheck                   as QC
+
+dupFolder :: (Eq a, Eq b) => Context a b -> [Context a b] -> [Context a b]
+dupFolder cont ns =
+  unique cont : ns
+  where
+    unique (a, b, c, d) = (nub a, b, c, nub d)
+
+-- | Remove duplicates.
+rDups :: (Eq a, Eq b) => Gr a b -> Gr a b
+rDups g = G.buildGr $ G.ufold dupFolder [] g
+
+-- | Gen instance to create an arbitrary edge, where the edges are limited by
+-- `n` that is passed to it.
+arbitraryEdge :: (Arbitrary e) => Int -> Gen (LEdge e)
+arbitraryEdge n = do
+  x <- with $ \a -> a < n && a > 0 && a /= n-1
+  y <- with $ \a -> x < a && a < n && a > 0
+  z <- QC.arbitrary
+  return (x, y, z)
+    where
+      with = QC.suchThat $ QC.resize n QC.arbitrary
+
+-- | Gen instance for a random acyclic DAG.
+randomDAG :: (Arbitrary l, Arbitrary e, Eq l, Eq e)
+          => Gen (Gr l e) -- ^ The generated graph. It uses Arbitrary to
+                          -- generate random instances of each node
+randomDAG = do
+  list <- QC.infiniteListOf QC.arbitrary
+  l <- QC.infiniteListOf aE
+  QC.sized (\n -> return . G.mkGraph (nodes list n) $ take (10*n) l)
+    where
+      nodes l n = zip [0..n] $ take n l
+      aE = QC.sized arbitraryEdge
+
+-- | Generate a random acyclic DAG with an IO instance.
+genRandomDAG :: (Arbitrary l, Arbitrary e, Eq l, Eq e)
+             => IO (Gr l e)
+genRandomDAG = QC.generate randomDAG
-- 
cgit