Replace function coinToInteger with safer equivalent.

We use `intCast` instead of `fromIntegral`, which statically checks
that the conversion is safe.

We also use the same naming convention as the existing safe conversion
functions.

lib/core/src/Cardano/Wallet.hs

@@ -373,7 +373,7 @@ import Cardano.Wallet.Primitive.Types
 import Cardano.Wallet.Primitive.Types.Address
     ( Address (..), AddressState (..) )
 import Cardano.Wallet.Primitive.Types.Coin
-    ( Coin (..), addCoin, coinToInteger, sumCoins )
+    ( Coin (..), addCoin, sumCoins )
 import Cardano.Wallet.Primitive.Types.Hash
     ( Hash (..) )
 import Cardano.Wallet.Primitive.Types.Redeemer
@@ -1160,7 +1160,7 @@ readNextWithdrawal ctx (Coin withdrawal) = do
             calcMinimumCost tl pp (mkTxCtx $ Coin 0) emptySkeleton
 
     let costOfWithdrawal =
-            coinToInteger costWith - coinToInteger costWithout
+            Coin.toInteger costWith - Coin.toInteger costWithout
 
     if toInteger withdrawal < 2 * costOfWithdrawal
     then pure (Coin 0)

lib/core/src/Cardano/Wallet/Primitive/Types/Coin.hs

@@ -18,6 +18,7 @@ module Cardano.Wallet.Primitive.Types.Coin
       -- * Conversions (Safe)
     , fromIntegral
     , fromWord64
+    , toInteger
     , toQuantity
     , toWord64
 
@@ -27,7 +28,6 @@ module Cardano.Wallet.Primitive.Types.Coin
     , unsafeToWord64
 
       -- * Compatibility
-    , coinToInteger
     , coinToNatural
     , unsafeNaturalToCoin
 
@@ -49,7 +49,7 @@ module Cardano.Wallet.Primitive.Types.Coin
     ) where
 
 import Prelude hiding
-    ( fromIntegral )
+    ( fromIntegral, toInteger )
 
 import Cardano.Numeric.Util
     ( equipartitionNatural, partitionNatural )
@@ -144,6 +144,11 @@ fromIntegral i = Coin <$> intCastMaybe i
 fromWord64 :: Word64 -> Coin
 fromWord64 = Coin . intCast
 
+-- | Converts a 'Coin' to an 'Integer' value.
+--
+toInteger :: Coin -> Integer
+toInteger = intCast . unCoin
+
 -- | Converts a 'Coin' to a 'Quantity'.
 --
 -- Returns 'Nothing' if the given value does not fit within the bounds of
@@ -224,9 +229,6 @@ unsafeToWord64 c = fromMaybe onError (toWord64 c)
                                Compatibility
 -------------------------------------------------------------------------------}
 
-coinToInteger :: Coin -> Integer
-coinToInteger = Prelude.fromIntegral . unCoin
-
 coinToNatural :: Coin -> Natural
 coinToNatural = unCoin
 

lib/shelley/test/unit/Cardano/Wallet/Shelley/TransactionSpec.hs

@@ -84,7 +84,7 @@ import Cardano.Wallet.Primitive.Types
 import Cardano.Wallet.Primitive.Types.Address
     ( Address (..) )
 import Cardano.Wallet.Primitive.Types.Coin
-    ( Coin (..), coinToInteger )
+    ( Coin (..) )
 import Cardano.Wallet.Primitive.Types.Coin.Gen
     ( genCoinPositive, shrinkCoinPositive )
 import Cardano.Wallet.Primitive.Types.Hash
@@ -661,11 +661,11 @@ feeCalculationSpec = describe "fee calculations" $ do
     fp = LinearFee (Quantity 100_000) (Quantity 100)
 
     minFee :: TransactionCtx -> Integer
-    minFee ctx = coinToInteger $ calcMinimumCost testTxLayer pp ctx sel
+    minFee ctx = Coin.toInteger $ calcMinimumCost testTxLayer pp ctx sel
       where sel = emptySkeleton
 
     minFeeSkeleton :: TxSkeleton -> Integer
-    minFeeSkeleton = coinToInteger . estimateTxCost pp
+    minFeeSkeleton = Coin.toInteger . estimateTxCost pp
 
     estimateTxSize' :: TxSkeleton -> Integer
     estimateTxSize' = fromIntegral . unTxSize . estimateTxSize