From 2f3f65a2273117a9de54c668247eb82e8490bbfd Mon Sep 17 00:00:00 2001
From: wiesche <wiesche89@googlemail.com>
Date: Sat, 12 Sep 2026 17:57:28 +0200
Subject: [PATCH] avoid slate copies

---
 libwallet/src/api_impl/owner.rs        |  3 +-
 libwallet/src/contract/actions/sign.rs | 13 ++++---
 libwallet/src/contract/actions/view.rs |  2 +-
 libwallet/src/slate.rs                 | 47 +++-----------------------
 4 files changed, 12 insertions(+), 53 deletions(-)

diff --git a/libwallet/src/api_impl/owner.rs b/libwallet/src/api_impl/owner.rs
index cf61036..00e0e7a 100644
--- a/libwallet/src/api_impl/owner.rs
+++ b/libwallet/src/api_impl/owner.rs
@@ -1615,8 +1615,7 @@ where
 	C: NodeClient,
 	K: Keychain,
 {
-	let mut slate = slate.clone();
-	contract::view(&mut *w, keychain_mask, &mut slate)
+	contract::view(&mut *w, keychain_mask, slate)
 }
 
 /// Sign transaction contract
diff --git a/libwallet/src/contract/actions/sign.rs b/libwallet/src/contract/actions/sign.rs
index e5c5ff1..8d981e3 100644
--- a/libwallet/src/contract/actions/sign.rs
+++ b/libwallet/src/contract/actions/sign.rs
@@ -92,28 +92,27 @@ where
 	C: NodeClient,
 	K: Keychain,
 {
-	let sl = slate.clone();
-	contract::utils::verify_not_signed(w, sl.id)?;
+	contract::utils::verify_not_signed(w, slate.id)?;
 	// Reject terminal and unknown states before setup reserves keys.
-	contract::slate::next_state(&sl.state)?;
+	contract::slate::next_state(&slate.state)?;
 
 	// Ensure net_change has been provided
 	let expected_net_change =
 		contract::utils::get_net_change(existing_context.as_ref(), setup_args.net_change)?;
 	if existing_context.is_none() {
-		verify_first_sign_net_change(&sl.state, sl.amount, expected_net_change)?;
+		verify_first_sign_net_change(&slate.state, slate.amount, expected_net_change)?;
 	}
 
 	// Define the values that must be provided in the setup phase at the sign step
 	let mut setup_args = setup_args.clone();
 	setup_args.net_change = Some(expected_net_change);
-	setup_args.num_participants = sl.num_participants;
+	setup_args.num_participants = slate.num_participants;
 	setup_args.add_outputs = true; // we add outputs to the Context in case we haven't done that yet
-	contract::slate::verify_incoming_own_commitments(w, keychain_mask, &sl)?;
+	contract::slate::verify_incoming_own_commitments(w, keychain_mask, slate)?;
 
 	// Ensure Setup phase is done and that inputs/outputs have been added to the Context
 	let (mut sl, mut context) =
-		setup::compute(w, keychain_mask, &sl, &setup_args, existing_context)?;
+		setup::compute(w, keychain_mask, slate, &setup_args, existing_context)?;
 	// Add outputs to the slate, verify the payment proof and sign the slate
 	contract::slate::add_outputs(w, keychain_mask, &mut sl, &context)?;
 	contract::slate::verify_own_commitments(w, keychain_mask, &sl, &context)?;
diff --git a/libwallet/src/contract/actions/view.rs b/libwallet/src/contract/actions/view.rs
index 7e99d8c..b0f32a8 100644
--- a/libwallet/src/contract/actions/view.rs
+++ b/libwallet/src/contract/actions/view.rs
@@ -58,7 +58,7 @@ fn tx_net_change(tx: &TxLogEntry) -> Result<i64, Error> {
 pub fn view<C, K>(
 	w: &mut WalletBackend<C, K>,
 	keychain_mask: Option<&SecretKey>,
-	slate: &mut Slate,
+	slate: &Slate,
 ) -> Result<ContractView, Error>
 where
 	C: NodeClient,
diff --git a/libwallet/src/slate.rs b/libwallet/src/slate.rs
index ffcba0c..bd72d44 100644
--- a/libwallet/src/slate.rs
+++ b/libwallet/src/slate.rs
@@ -975,47 +975,7 @@ impl Serialize for Slate {
 ////// V5
 impl From<Slate> for SlateV5 {
 	fn from(slate: Slate) -> SlateV5 {
-		let Slate {
-			num_participants: num_parts,
-			id,
-			state,
-			tx: _,
-			amount,
-			fee_fields,
-			kernel_features,
-			ttl_cutoff_height: ttl,
-			offset: off,
-			participant_data,
-			version_info,
-			payment_proof,
-			kernel_features_args,
-		} = slate.clone();
-		let participant_data = map_vec!(participant_data, |data| ParticipantDataV5::from(data));
-		let ver = VersionCompatInfoV5::from(&version_info);
-		let payment_proof = match payment_proof {
-			Some(p) => Some(PaymentInfoV5::from(&p)),
-			None => None,
-		};
-		let feat_args = match kernel_features_args {
-			Some(a) => Some(KernelFeaturesArgsV5::from(&a)),
-			None => None,
-		};
-		let sta = SlateStateV5::from(&state);
-		SlateV5 {
-			num_parts,
-			id,
-			sta,
-			coms: (&slate).into(),
-			amt: amount,
-			fee: fee_fields,
-			feat: kernel_features,
-			ttl,
-			off,
-			sigs: participant_data,
-			ver,
-			proof: payment_proof,
-			feat_args,
-		}
+		Self::from(&slate)
 	}
 }
 
@@ -1191,6 +1151,7 @@ impl From<OutputFeatures> for OutputFeaturesV5 {
 ///// V5
 impl From<SlateV5> for Slate {
 	fn from(slate: SlateV5) -> Slate {
+		let tx = (&slate).into();
 		let SlateV5 {
 			num_parts: num_participants,
 			id,
@@ -1205,7 +1166,7 @@ impl From<SlateV5> for Slate {
 			ver,
 			proof: payment_proof,
 			feat_args,
-		} = slate.clone();
+		} = slate;
 		let participant_data = map_vec!(participant_data, |data| ParticipantData::from(data));
 		let version_info = VersionCompatInfo::from(&ver);
 		let payment_proof = match &payment_proof {
@@ -1221,7 +1182,7 @@ impl From<SlateV5> for Slate {
 			num_participants,
 			id,
 			state,
-			tx: (&slate).into(),
+			tx,
 			amount,
 			fee_fields,
 			kernel_features,