From debcce6a0388bf89d68e04ce2f2a55038a081683 Mon Sep 17 00:00:00 2001
From: DanGould <d@ngould.dev>
Date: Mon, 9 Jan 2023 23:10:07 -0500
Subject: [PATCH 1/3] Improve magic bytes push performance

---
 bitcoin/src/psbt/serialize.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bitcoin/src/psbt/serialize.rs b/bitcoin/src/psbt/serialize.rs
index ddbe2ec8..61019f62 100644
--- a/bitcoin/src/psbt/serialize.rs
+++ b/bitcoin/src/psbt/serialize.rs
@@ -53,7 +53,7 @@ impl PartiallySignedTransaction {
         let mut buf: Vec<u8> = Vec::new();
 
         //  <magic>
-        buf.extend(b"psbt");
+        buf.extend_from_slice(b"psbt");
 
         buf.push(0xff_u8);
 

From 81ca10701aeed5b6856f7f82877dc09bd4a6adf6 Mon Sep 17 00:00:00 2001
From: DanGould <d@ngould.dev>
Date: Mon, 9 Jan 2023 23:17:04 -0500
Subject: [PATCH 2/3] Use as_ref() instead of costly clone()

---
 bitcoin/tests/psbt.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/bitcoin/tests/psbt.rs b/bitcoin/tests/psbt.rs
index 389f1727..e78b0b54 100644
--- a/bitcoin/tests/psbt.rs
+++ b/bitcoin/tests/psbt.rs
@@ -437,7 +437,7 @@ fn finalize_psbt(mut psbt: Psbt) -> Psbt {
     // Input 1: SegWit UTXO
 
     let script_sig = script::Builder::new()
-        .push_slice(psbt.inputs[1].redeem_script.clone().unwrap().as_bytes())
+        .push_slice(psbt.inputs[1].redeem_script.as_ref().unwrap().as_bytes())
         .into_script();
 
     psbt.inputs[1].final_script_sig = Some(script_sig);

From 1a409ecc8e953041588408526d6f13a50b6cc74b Mon Sep 17 00:00:00 2001
From: DanGould <d@ngould.dev>
Date: Mon, 9 Jan 2023 23:21:20 -0500
Subject: [PATCH 3/3] Use &[u8] instead of Cursor as Read

---
 bitcoin/src/psbt/macros.rs | 2 +-
 bitcoin/src/psbt/raw.rs    | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/bitcoin/src/psbt/macros.rs b/bitcoin/src/psbt/macros.rs
index dd820e81..a5aedd3d 100644
--- a/bitcoin/src/psbt/macros.rs
+++ b/bitcoin/src/psbt/macros.rs
@@ -54,7 +54,7 @@ macro_rules! impl_psbtmap_deserialize {
     ($thing:ty) => {
         impl $crate::psbt::serialize::Deserialize for $thing {
             fn deserialize(bytes: &[u8]) -> Result<Self, $crate::consensus::encode::Error> {
-                let mut decoder = crate::io::Cursor::new(bytes);
+                let mut decoder = bytes;
                 Self::decode(&mut decoder)
             }
         }
diff --git a/bitcoin/src/psbt/raw.rs b/bitcoin/src/psbt/raw.rs
index e9770b65..f8720057 100644
--- a/bitcoin/src/psbt/raw.rs
+++ b/bitcoin/src/psbt/raw.rs
@@ -11,7 +11,7 @@ use crate::prelude::*;
 use core::fmt;
 use core::convert::TryFrom;
 
-use crate::io::{self, Cursor};
+use crate::io;
 use crate::consensus::encode::{self, ReadExt, WriteExt, Decodable, Encodable, VarInt, serialize, deserialize, MAX_VEC_SIZE};
 use crate::psbt::Error;
 
@@ -125,7 +125,7 @@ impl Serialize for Pair {
 
 impl Deserialize for Pair {
     fn deserialize(bytes: &[u8]) -> Result<Self, encode::Error> {
-        let mut decoder = Cursor::new(bytes);
+        let mut decoder = bytes;
         Pair::decode(&mut decoder)
     }
 }