From f645f46a69a76a0dc5a6311864dc7a9194fcc364 Mon Sep 17 00:00:00 2001
From: wiesche <wiesche89@googlemail.com>
Date: Sat, 12 Sep 2026 17:17:51 +0200
Subject: [PATCH] simplify proof serde

---
 libwallet/src/contract/types.rs    |  7 ++++++-
 libwallet/src/payment_proof.rs     |  1 -
 libwallet/src/slate.rs             | 21 ++++++++++-----------
 libwallet/src/slate_versions/v5.rs |  1 -
 4 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/libwallet/src/contract/types.rs b/libwallet/src/contract/types.rs
index fda442e..f2a39cb 100644
--- a/libwallet/src/contract/types.rs
+++ b/libwallet/src/contract/types.rs
@@ -95,7 +95,6 @@ pub struct ProofArgs {
 	/// If net change is positive during this step, whether to suppress the creation of payment proof
 	pub suppress_proof: bool,
 	/// Requested early payment proof type
-	#[serde(with = "crate::slate::payment_proof_type_serde")]
 	pub proof_type: ProofType,
 	/// Memo used when this step creates the payment proof
 	pub memo: Option<PaymentMemo>,
@@ -257,6 +256,11 @@ mod tests {
 			(ProofType::Invoice, 1),
 			(ProofType::SenderNonce, 2),
 		] {
+			assert_eq!(serde_json::to_value(proof_type).unwrap(), value);
+			assert_eq!(
+				serde_json::from_value::<ProofType>(serde_json::json!(value)).unwrap(),
+				proof_type
+			);
 			let args = ProofArgs {
 				proof_type,
 				..Default::default()
@@ -268,6 +272,7 @@ mod tests {
 		}
 		let mut json = serde_json::to_value(ProofArgs::default()).unwrap();
 		for invalid in [serde_json::json!(3), serde_json::json!("Invoice")] {
+			assert!(serde_json::from_value::<ProofType>(invalid.clone()).is_err());
 			json["proof_type"] = invalid;
 			assert!(serde_json::from_value::<ProofArgs>(json.clone()).is_err());
 		}
diff --git a/libwallet/src/payment_proof.rs b/libwallet/src/payment_proof.rs
index 342ca90..ef6e26d 100644
--- a/libwallet/src/payment_proof.rs
+++ b/libwallet/src/payment_proof.rs
@@ -127,7 +127,6 @@ pub struct ProofWitness {
 #[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Eq)]
 pub struct EarlyPaymentProof {
 	/// Proof type
-	#[serde(with = "crate::slate::payment_proof_type_serde")]
 	pub proof_type: PaymentProofType,
 	/// amount
 	#[serde(with = "secp_ser::string_or_u64")]
diff --git a/libwallet/src/slate.rs b/libwallet/src/slate.rs
index 7cbc929..ffcba0c 100644
--- a/libwallet/src/slate.rs
+++ b/libwallet/src/slate.rs
@@ -51,7 +51,7 @@ use crate::Context;
 
 /// Payment proof type from https://github.com/mimblewimble/grin-rfcs/pull/70
 #[repr(u8)]
-#[derive(Clone, Copy, Serialize, Deserialize, Debug, Eq, PartialEq)]
+#[derive(Clone, Copy, Debug, Eq, PartialEq)]
 pub enum PaymentProofType {
 	/// Legacy payment proof
 	Legacy = 0,
@@ -95,23 +95,22 @@ impl TryFrom<u8> for PaymentProofType {
 	}
 }
 
-pub(crate) mod payment_proof_type_serde {
-	use super::PaymentProofType;
-	use serde::{Deserialize, Deserializer, Serializer};
-
-	pub fn serialize<S>(proof_type: &PaymentProofType, serializer: S) -> Result<S::Ok, S::Error>
+impl serde::Serialize for PaymentProofType {
+	fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
 	where
-		S: Serializer,
+		S: serde::Serializer,
 	{
-		serializer.serialize_u8(proof_type.as_u8())
+		serializer.serialize_u8(self.as_u8())
 	}
+}
 
-	pub fn deserialize<'de, D>(deserializer: D) -> Result<PaymentProofType, D::Error>
+impl<'de> serde::Deserialize<'de> for PaymentProofType {
+	fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
 	where
-		D: Deserializer<'de>,
+		D: serde::Deserializer<'de>,
 	{
 		let value = u8::deserialize(deserializer)?;
-		PaymentProofType::try_from(value).map_err(serde::de::Error::custom)
+		Self::try_from(value).map_err(serde::de::Error::custom)
 	}
 }
 
diff --git a/libwallet/src/slate_versions/v5.rs b/libwallet/src/slate_versions/v5.rs
index d30aba9..b621e03 100644
--- a/libwallet/src/slate_versions/v5.rs
+++ b/libwallet/src/slate_versions/v5.rs
@@ -196,7 +196,6 @@ fn default_part_sig_none() -> Option<Signature> {
 #[serde_as]
 #[derive(Serialize, Deserialize, Debug, Clone, Eq, PartialEq)]
 pub struct PaymentInfoV5 {
-	#[serde(with = "crate::slate::payment_proof_type_serde")]
 	pub ptype: PaymentProofType,
 	#[serde(default)]
 	#[serde(with = "ser::option_dalek_pubkey_serde")]