Move isZero TxOut Check

Author: MitchyCola

src/BotPlutusInterface/Balance.hs

@@ -136,16 +136,20 @@ balanceTxIO' balanceCfg pabConf ownPkh unbalancedTx =
             (unBalancedTxValidityTimeRange unbalancedTx)
             (unBalancedTxTx unbalancedTx)
 
+      -- Checks that there is a non-zero output in the transaction.
       -- Adds required collaterals in the `Tx`, if `bcHasScripts`
       -- is true. Also adds signatures for fee calculation
       preBalancedTx <-
-        if bcHasScripts balanceCfg
-          then
-            maybe
-              (throwE $ WAPI.OtherError "Tx uses script but no collateral was provided.")
-              (hoistEither . addSignatories ownPkh privKeys requiredSigs . flip addTxCollaterals tx)
-              mcollateral
-          else hoistEither $ addSignatories ownPkh privKeys requiredSigs tx
+        if all (Value.isZero . txOutValue) (Tx.txOutputs tx)
+          then throwE $ WAPI.OtherError "When constructing the transaction, no output values were specified."
+          else
+            if bcHasScripts balanceCfg
+              then
+                maybe
+                  (throwE $ WAPI.OtherError "Tx uses script but no collateral was provided.")
+                  (hoistEither . addSignatories ownPkh privKeys requiredSigs . flip addTxCollaterals tx)
+                  mcollateral
+              else hoistEither $ addSignatories ownPkh privKeys requiredSigs tx
 
       -- Balance the tx
       (balancedTx, minUtxos) <- balanceTxLoop utxoIndex privKeys [] preBalancedTx

src/BotPlutusInterface/CardanoCLI.hs

@@ -143,22 +143,18 @@ calculateMinUtxo ::
   TxOut ->
   Eff effs (Either Text Integer)
 calculateMinUtxo pabConf datums txOut = do
-  let outs = txOutOpts pabConf datums [txOut]
-  case outs of
-    [] -> pure $ Left "When constructing the transaction, no output values were specified."
-    _ ->
-      join
-        <$> callCommand @w
-          ShellArgs
-            { cmdName = "cardano-cli"
-            , cmdArgs =
-                mconcat
-                  [ ["transaction", "calculate-min-required-utxo", "--alonzo-era"]
-                  , outs
-                  , ["--protocol-params-file", pabConf.pcProtocolParamsFile]
-                  ]
-            , cmdOutParser = mapLeft Text.pack . parseOnly UtxoParser.feeParser . Text.pack
-            }
+  join
+    <$> callCommand @w
+      ShellArgs
+        { cmdName = "cardano-cli"
+        , cmdArgs =
+            mconcat
+              [ ["transaction", "calculate-min-required-utxo", "--alonzo-era"]
+              , txOutOpts pabConf datums [txOut]
+              , ["--protocol-params-file", pabConf.pcProtocolParamsFile]
+              ]
+        , cmdOutParser = mapLeft Text.pack . parseOnly UtxoParser.feeParser . Text.pack
+        }
 
 -- | Calculating fee for an unbalanced transaction
 calculateMinFee ::
@@ -212,6 +208,7 @@ buildTx pabConf privKeys txBudget tx = do
                     []
         )
         (Map.keys (Ledger.txSignatures tx))
+
     opts ins mints =
       mconcat
         [ ["transaction", "build-raw", "--alonzo-era"]