Add separate UTxO generators

Instead of using the UTxOIndex generators, and converting back to UTxOs,
this commits adds generators for UTxO.

1. Mimic the generators in UTxOIndex.Gen
2. Make UTxOIndex.Gen use UTxO.Gen
3. Use UTxO.Gen in ServerSpec

In response to the suggestion #2684 (comment)

lib/core/cardano-wallet-core.cabal

@@ -231,6 +231,7 @@ library
       Cardano.Wallet.Primitive.Types.TokenQuantity.Gen
       Cardano.Wallet.Primitive.Types.Tx.Gen
       Cardano.Wallet.Primitive.Types.UTxOIndex.Gen
+      Cardano.Wallet.Primitive.Types.UTxO.Gen
   other-modules:
       Paths_cardano_wallet_core
 

lib/core/src/Cardano/Wallet/Primitive/Types/UTxO/Gen.hs

@@ -0,0 +1,79 @@
+module Cardano.Wallet.Primitive.Types.UTxO.Gen
+    ( genUTxOSmall
+    , genUTxOLarge
+    , genUTxOLargeN
+    , shrinkUTxOSmall
+    ) where
+
+import Prelude
+
+import Cardano.Wallet.Primitive.Types.Tx
+    ( TxIn, TxOut )
+import Cardano.Wallet.Primitive.Types.Tx.Gen
+    ( genTxInLargeRange
+    , genTxInSmallRange
+    , genTxOutSmallRange
+    , shrinkTxInSmallRange
+    , shrinkTxOutSmallRange
+    )
+import Cardano.Wallet.Primitive.Types.UTxO
+    ( UTxO (..) )
+import Control.Monad
+    ( replicateM )
+import Test.QuickCheck
+    ( Gen, choose, frequency, shrinkList )
+import Test.QuickCheck.Extra
+    ( shrinkInterleaved )
+
+import qualified Data.Map as Map
+
+--------------------------------------------------------------------------------
+-- Small indices
+--------------------------------------------------------------------------------
+
+genUTxOSmall :: Gen UTxO
+genUTxOSmall = do
+    entryCount <- frequency
+        [ (1, pure 0)
+        , (1, pure 1)
+        , (32, choose (2, 64))
+        ]
+    UTxO . Map.fromList <$> replicateM entryCount genEntrySmallRange
+
+shrinkUTxOSmall :: UTxO -> [UTxO]
+shrinkUTxOSmall
+    = take 16
+    . fmap (UTxO . Map.fromList)
+    . shrinkList shrinkEntrySmallRange
+    . Map.toList
+    . getUTxO
+
+genEntrySmallRange :: Gen (TxIn, TxOut)
+genEntrySmallRange = (,)
+    <$> genTxInSmallRange
+    <*> genTxOutSmallRange
+
+shrinkEntrySmallRange :: (TxIn, TxOut) -> [(TxIn, TxOut)]
+shrinkEntrySmallRange (i, o) = uncurry (,) <$> shrinkInterleaved
+    (i, shrinkTxInSmallRange)
+    (o, shrinkTxOutSmallRange)
+
+--------------------------------------------------------------------------------
+-- Large indices
+--------------------------------------------------------------------------------
+
+genUTxOLarge :: Gen UTxO
+genUTxOLarge = do
+    entryCount <- choose (1024, 4096)
+    genUTxOLargeN entryCount
+
+genUTxOLargeN :: Int -> Gen UTxO
+genUTxOLargeN entryCount = do
+    UTxO . Map.fromList <$> replicateM entryCount genEntryLargeRange
+
+genEntryLargeRange :: Gen (TxIn, TxOut)
+genEntryLargeRange = (,)
+    <$> genTxInLargeRange
+    -- Note that we don't need to choose outputs from a large range, as inputs
+    -- are already chosen from a large range:
+    <*> genTxOutSmallRange

lib/core/src/Cardano/Wallet/Primitive/Types/UTxOIndex/Gen.hs

@@ -10,18 +10,13 @@ import Prelude
 import Cardano.Wallet.Primitive.Types.Tx
     ( TxIn, TxOut )
 import Cardano.Wallet.Primitive.Types.Tx.Gen
-    ( genTxInLargeRange
-    , genTxInSmallRange
-    , genTxOutSmallRange
-    , shrinkTxInSmallRange
-    , shrinkTxOutSmallRange
-    )
+    ( shrinkTxInSmallRange, shrinkTxOutSmallRange )
+import Cardano.Wallet.Primitive.Types.UTxO.Gen
+    ( genUTxOLargeN, genUTxOSmall )
 import Cardano.Wallet.Primitive.Types.UTxOIndex
     ( UTxOIndex )
-import Control.Monad
-    ( replicateM )
 import Test.QuickCheck
-    ( Gen, choose, frequency, shrinkList )
+    ( Gen, choose, shrinkList )
 import Test.QuickCheck.Extra
     ( shrinkInterleaved )
 
@@ -32,13 +27,7 @@ import qualified Cardano.Wallet.Primitive.Types.UTxOIndex as UTxOIndex
 --------------------------------------------------------------------------------
 
 genUTxOIndexSmall :: Gen UTxOIndex
-genUTxOIndexSmall = do
-    entryCount <- frequency
-        [ (1, pure 0)
-        , (1, pure 1)
-        , (32, choose (2, 64))
-        ]
-    UTxOIndex.fromSequence <$> replicateM entryCount genEntrySmallRange
+genUTxOIndexSmall = UTxOIndex.fromUTxO <$> genUTxOSmall
 
 shrinkUTxOIndexSmall :: UTxOIndex -> [UTxOIndex]
 shrinkUTxOIndexSmall
@@ -47,11 +36,6 @@ shrinkUTxOIndexSmall
     . shrinkList shrinkEntrySmallRange
     . UTxOIndex.toList
 
-genEntrySmallRange :: Gen (TxIn, TxOut)
-genEntrySmallRange = (,)
-    <$> genTxInSmallRange
-    <*> genTxOutSmallRange
-
 shrinkEntrySmallRange :: (TxIn, TxOut) -> [(TxIn, TxOut)]
 shrinkEntrySmallRange (i, o) = uncurry (,) <$> shrinkInterleaved
     (i, shrinkTxInSmallRange)
@@ -68,11 +52,4 @@ genUTxOIndexLarge = do
 
 genUTxOIndexLargeN :: Int -> Gen UTxOIndex
 genUTxOIndexLargeN entryCount = do
-    UTxOIndex.fromSequence <$> replicateM entryCount genEntryLargeRange
-
-genEntryLargeRange :: Gen (TxIn, TxOut)
-genEntryLargeRange = (,)
-    <$> genTxInLargeRange
-    -- Note that we don't need to choose outputs from a large range, as inputs
-    -- are already chosen from a large range:
-    <*> genTxOutSmallRange
+    UTxOIndex.fromUTxO <$> genUTxOLargeN entryCount

lib/core/test/unit/Cardano/Wallet/Api/ServerSpec.hs

@@ -66,10 +66,8 @@ import Cardano.Wallet.Primitive.Types.RewardAccount
     ( RewardAccount (..) )
 import Cardano.Wallet.Primitive.Types.UTxO
     ( UTxO, balance )
-import Cardano.Wallet.Primitive.Types.UTxOIndex
-    ( fromUTxO, toUTxO )
-import Cardano.Wallet.Primitive.Types.UTxOIndex.Gen
-    ( genUTxOIndexSmall, shrinkUTxOIndexSmall )
+import Cardano.Wallet.Primitive.Types.UTxO.Gen
+    ( genUTxOSmall, shrinkUTxOSmall )
 import Cardano.Wallet.Unsafe
     ( unsafeFromText )
 import Control.Monad
@@ -413,8 +411,8 @@ accountOfAddress (Address bytes) =
         else Just $ RewardAccount $ B8.pack [char]
 
 instance Arbitrary UTxO where
-    arbitrary = toUTxO <$> genUTxOIndexSmall
-    shrink = map toUTxO . shrinkUTxOIndexSmall . fromUTxO
+    arbitrary = genUTxOSmall
+    shrink = shrinkUTxOSmall
 
 instance Arbitrary Natural where
     arbitrary = fromIntegral . getNonNegative @Int <$> arbitrary