feat: improve witness updates

Reviewed-on: https://git.vergara.tech///Vergara_Tech/zcash-haskell/pulls/93

CHANGELOG.md

@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.7.0.2]
+
+## Changed
+
+- Modified witness update functions to skip the process if no commitments are present
+
 ## [0.7.0.1]
 
 ### Added

src/ZcashHaskell/Orchard.hs

@@ -229,9 +229,13 @@ getOrchardNotePosition =
 -- | Update the witness of an Orchard note
 updateOrchardWitness :: OrchardWitness -> [HexString] -> OrchardWitness
 updateOrchardWitness wit cmus =
-  OrchardWitness $
-  withPureBorshVarBuffer $
-  rustWrapperUpdateOrchardWitness (toBytes $ orchWit wit) (map toBytes cmus)
+  if not (null cmus)
+    then OrchardWitness $
+         withPureBorshVarBuffer $
+         rustWrapperUpdateOrchardWitness
+           (toBytes $ orchWit wit)
+           (map toBytes cmus)
+    else wit
 
 -- | Parse a potential Zcash address
 parseAddress :: BS.ByteString -> Maybe ValidAddress

src/ZcashHaskell/Sapling.hs

@@ -218,9 +218,13 @@ getSaplingNotePosition =
 
 updateSaplingWitness :: SaplingWitness -> [HexString] -> SaplingWitness
 updateSaplingWitness wit cmus =
-  SaplingWitness $
-  withPureBorshVarBuffer $
-  rustWrapperUpdateSaplingWitness (toBytes $ sapWit wit) (map toBytes cmus)
+  if not (null cmus)
+    then SaplingWitness $
+         withPureBorshVarBuffer $
+         rustWrapperUpdateSaplingWitness
+           (toBytes $ sapWit wit)
+           (map toBytes cmus)
+    else wit
 
 -- | Encode a SaplingReceiver into HRF text
 encodeSaplingAddress :: ZcashNet -> SaplingReceiver -> Maybe T.Text

zcash-haskell.cabal

@@ -5,7 +5,7 @@ cabal-version: 3.0
 -- see: https://github.com/sol/hpack
 
 name:           zcash-haskell
-version:        0.7.0.1
+version:        0.7.0.2
 synopsis:       Utilities to interact with the Zcash blockchain
 description:    Please see the README on the repo at <https://git.vergara.tech/Vergara_Tech/zcash-haskell#readme>
 category:       Blockchain