Append change instead of prepending it

It's desirable for a client to be able to predict the index of outputs.
As such we append change to the end so that the index of other outputs
doesn't changed based on whether there's change or not.

Resolves #3725

Author: Robert 'Probie' Offner

cardano-api/ChangeLog.md

@@ -1,65 +1,10 @@
 # Changelog for cardano-api
 
-## 1.35.3 -- August 2022
+## vNext
 
-- Fix leadership schedule for current on babbage (#4106)
-- Update build to allow all invalid scripts (again) (#4088)
-- Fix building of Alonzo transaction in Babbage era. (#4166)
-- Add `utxoCostPerByte` protocol parameter (#4141)
+### Features
 
-## 1.35.2 -- July 2022 (not released)
-
-None
-
-## 1.35.1 -- July 2022 (not released)
-
-None
-
-## 1.35.0 -- June 2022
-- Add Vasil hardfork to cardano-api and cardano-cli (#3765)
-- Reference script integration (#3953)
-- Wire up remaining Plutusv2 reference script types (#4034)
-- Add `IsString` (Hash BlockHeader) (#3619)
-- Make `LedgerStateEvents` a type alias (#3692)
-- Propagate protocol epoch state decode error (#3696)
-- Expose the tx mempool monitoring mini protocol in cardano-api (#3706)
-- Babbage functionality integration in cardano api Part 1 (#3803)
-- Remove unused package (#3816)
-- Add `IsCardanoEra` constraint to BlockInMode (#3665)
-- Update cardano-api's TxOut with inline datum (#3773)
-- Update cardano-api txout with reference scripts (#3779)
-- Implement return and total collateral in cardano-api (#3787)
-- Add reference transaction inputs to cardano-api (#3804)
-- Fix datum in tx and ref scripts (#3882)
-- Support the babbage era in the API function `cddlTypeToEra` (#3916)
-- Fix typo for TxWitness BabbageEra (#3961)
-- kes-period-info property test (#3718)
-- Extend deserialiseFromRawBytesHex to produce error description (#3304)
-- add genesis create-cardano command (#3832)
-- Propagate protocol in block type (#3818)
-- Create VRF signing key file with correct permissions (#1948)
-- Update example-reference-script-usage.sh to also use inline datums (#4006)
-- Restore deleted comment (#4044)
-- Do not require decentralization parameter in protocol parameters (#4051)
-
-
-## 1.34.0 -- February 2022
-
-- Expose `lovelaceToTxOutValue`. (#3381)
-- Implement two functions: `currentEpochEligibleLeadershipSlots` and
-  `nextEpochEligibleLeadershipSlots` to get the leadership slots for the
-  current/next epoch respectively. (#3464, #3494)
-- Various small intenral fixes. (#3466)
-- Add a `capi` library to support using the cardano node as a C library in other
-  software. (#3501)
-- `fromShelleyAddr` now takes an explicit `ShelleyBasedEra` parameter to
-  determine the era. The previous behaviour (with an implicit
-  `IsShelleyBasedEra` constraint) can be obtained with `fromShelleyAddrIsSbe`.
-  (#2253, #3606)
-
-### Bugs
-
-- Allow reading text envelopes from pipes ([PR 4384](https://github.com/input-output-hk/cardano-node/pull/4384))
+- Append, not prepend change output when balancing a transaction ([PR 4343](https://github.com/input-output-hk/cardano-node/pull/4343))
 
 ## 1.33.0 -- December 2021
 ## 1.32.1 -- November 2021

cardano-api/src/Cardano/Api/Fees.hs

@@ -1129,7 +1129,9 @@ makeTransactionBodyAutoBalance eraInMode systemstart history pparams
    accountForNoChange change@(TxOut _ balance _ _) rest =
      case txOutValueToLovelace balance of
        Lovelace 0 -> rest
-       _ -> change : rest
+       -- We append change at the end so a client can predict the indexes
+       -- of the outputs
+       _ -> rest ++ [change]
 
    balanceCheck :: TxOutValue era -> Either TxBodyErrorAutoBalance ()
    balanceCheck balance