Make the arbitraryScriptOf generator more general and use it more

Rather than arbitraryShortScriptOf which was fixed to scripts of exactly
5, we now pick any size between 1 and any max size (but still capped by
the QC size). So this will give more variation in script size.

For gossip scripts, this will give more variation, and we also change
the max size from being 5 to the square root of the QC size, so that
will scale up to 10 for size 100.

ouroboros-network/test/Test/Ouroboros/Network/PeerSelection/PeerGraph.hs

@@ -255,7 +255,8 @@ instance Arbitrary PeerGraph where
 
 arbitraryGossipScript :: [PeerAddr] -> Gen GossipScript
 arbitraryGossipScript peers =
-    arbitraryShortScriptOf gossipResult
+    sized $ \sz ->
+      arbitraryScriptOf (isqrt sz) gossipResult
   where
     gossipResult :: Gen (Maybe ([PeerAddr], GossipTime))
     gossipResult =
@@ -268,6 +269,9 @@ arbitraryGossipScript peers =
         picked <- vectorOf (length xs) arbitrary
         return [ x | (x, True) <- zip xs picked ]
 
+isqrt :: Int -> Int
+isqrt = floor . sqrt . (fromIntegral :: Int -> Double)
+
 -- | Remove dangling graph edges and gossip results.
 --
 prunePeerGraphEdges :: [(PeerAddr, [PeerAddr], PeerInfo)]

ouroboros-network/test/Test/Ouroboros/Network/PeerSelection/Script.hs

@@ -10,7 +10,7 @@ module Test.Ouroboros.Network.PeerSelection.Script (
     initScript,
     stepScript,
     stepScriptSTM,
-    arbitraryShortScriptOf,
+    arbitraryScriptOf,
 
     -- * Timed scripts
     ScriptDelay(..),
@@ -51,10 +51,11 @@ singletonScript x = (Script (x :| []))
 scriptHead :: Script a -> a
 scriptHead (Script (x :| _)) = x
 
-arbitraryShortScriptOf :: Gen a -> Gen (Script a)
-arbitraryShortScriptOf a =
-    sized $ \sz ->
-      (Script . NonEmpty.fromList) <$> vectorOf (min 5 (sz+1)) a
+arbitraryScriptOf :: Int -> Gen a -> Gen (Script a)
+arbitraryScriptOf maxSz a =
+    sized $ \sz -> do
+      n <- choose (1, max 1 (min maxSz sz))
+      (Script . NonEmpty.fromList) <$> vectorOf n a
 
 initScript :: MonadSTM m => Script a -> m (TVar m (Script a))
 initScript = newTVarIO
@@ -71,7 +72,7 @@ stepScriptSTM scriptVar = do
     return x
 
 instance Arbitrary a => Arbitrary (Script a) where
-    arbitrary = (Script . NonEmpty.fromList) <$> listOf1 arbitrary
+    arbitrary = sized $ \sz -> arbitraryScriptOf sz arbitrary
 
     shrink (Script (x :| [])) = [ Script (x' :| []) | x' <- shrink x ]
     shrink (Script (x :| xs)) =