From 86142d044c0670b288c96f9e9fa9183eba74f2b0 Mon Sep 17 00:00:00 2001
From: Jack Grigg <jack@z.cash>
Date: Fri, 23 Aug 2019 23:03:16 +0100
Subject: [PATCH] PaymentAddress::to_bytes

---
 librustzcash/src/rustzcash.rs        | 9 +--------
 zcash_client_backend/src/encoding.rs | 5 +----
 zcash_primitives/src/primitives.rs   | 8 ++++++++
 3 files changed, 10 insertions(+), 12 deletions(-)

diff --git a/librustzcash/src/rustzcash.rs b/librustzcash/src/rustzcash.rs
index 9df4437..e3a85e4 100644
--- a/librustzcash/src/rustzcash.rs
+++ b/librustzcash/src/rustzcash.rs
@@ -1215,14 +1215,7 @@ pub extern "system" fn librustzcash_zip32_xfvk_address(
     let addr_ret = unsafe { &mut *addr_ret };
 
     j_ret.copy_from_slice(&(addr.0).0);
-    addr_ret
-        .get_mut(..11)
-        .unwrap()
-        .copy_from_slice(&addr.1.diversifier.0);
-    addr.1
-        .pk_d
-        .write(addr_ret.get_mut(11..).unwrap())
-        .expect("should be able to serialize a PaymentAddress");
+    addr_ret.copy_from_slice(&addr.1.to_bytes());
 
     true
 }
diff --git a/zcash_client_backend/src/encoding.rs b/zcash_client_backend/src/encoding.rs
index 9e9f2fc..4d87587 100644
--- a/zcash_client_backend/src/encoding.rs
+++ b/zcash_client_backend/src/encoding.rs
@@ -121,10 +121,7 @@ pub fn decode_extended_full_viewing_key(
 /// );
 /// ```
 pub fn encode_payment_address(hrp: &str, addr: &PaymentAddress<Bls12>) -> String {
-    bech32_encode(hrp, |w| {
-        w.write_all(&addr.diversifier.0)?;
-        addr.pk_d.write(w)
-    })
+    bech32_encode(hrp, |w| w.write_all(&addr.to_bytes()))
 }
 
 /// Decodes a [`PaymentAddress`] from a Bech32-encoded string.
diff --git a/zcash_primitives/src/primitives.rs b/zcash_primitives/src/primitives.rs
index ac22f15..00ff2bf 100644
--- a/zcash_primitives/src/primitives.rs
+++ b/zcash_primitives/src/primitives.rs
@@ -155,6 +155,14 @@ impl<E: JubjubEngine> PaymentAddress<E> {
             })
     }
 
+    /// Returns the byte encoding of this `PaymentAddress`.
+    pub fn to_bytes(&self) -> [u8; 43] {
+        let mut bytes = [0; 43];
+        bytes[0..11].copy_from_slice(&self.diversifier.0);
+        self.pk_d.write(&mut bytes[11..]).unwrap();
+        bytes
+    }
+
     pub fn g_d(&self, params: &E::Params) -> Option<edwards::Point<E, PrimeOrder>> {
         self.diversifier.g_d(params)
     }