From 0225b530ccd5f6d3d44a27b8a5690008819830ad Mon Sep 17 00:00:00 2001
From: Jean Pierre Dudey <jeandudey@hotmail.com>
Date: Wed, 8 Aug 2018 19:11:16 -0400
Subject: [PATCH] Implement `Display` trait instead of implementing `ToString`
 directly.

ExtendedPubKey and ExtendedPrivKey implemented `ToString` directly but
Rust documentation says to implement `Display` and get the `ToString`
implementation for free.

Signed-off-by: Jean Pierre Dudey <jeandudey@hotmail.com>
---
 src/util/bip32.rs | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/src/util/bip32.rs b/src/util/bip32.rs
index 3af594d..fafa144 100644
--- a/src/util/bip32.rs
+++ b/src/util/bip32.rs
@@ -20,7 +20,6 @@ use std::default::Default;
 use std::io::Cursor;
 use std::{error, fmt};
 use std::str::FromStr;
-use std::string::ToString;
 use serde::{Serialize, Deserialize, Serializer, Deserializer};
 
 use byteorder::{BigEndian, ByteOrder, ReadBytesExt};
@@ -339,8 +338,8 @@ impl ExtendedPubKey {
     }
 }
 
-impl ToString for ExtendedPrivKey {
-    fn to_string(&self) -> String {
+impl fmt::Display for ExtendedPrivKey {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
         let mut ret = [0; 78];
         ret[0..4].copy_from_slice(&match self.network {
             Network::Bitcoin => [0x04, 0x88, 0xAD, 0xE4],
@@ -359,7 +358,7 @@ impl ToString for ExtendedPrivKey {
         ret[13..45].copy_from_slice(&self.chain_code[..]);
         ret[45] = 0;
         ret[46..78].copy_from_slice(&self.secret_key[..]);
-        base58::check_encode_slice(&ret[..])
+        fmt.write_str(&base58::check_encode_slice(&ret[..]))
     }
 }
 
@@ -397,8 +396,8 @@ impl FromStr for ExtendedPrivKey {
     }
 }
 
-impl ToString for ExtendedPubKey {
-    fn to_string(&self) -> String {
+impl fmt::Display for ExtendedPubKey {
+    fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
         let mut ret = [0; 78];
         ret[0..4].copy_from_slice(&match self.network {
             Network::Bitcoin => [0x04u8, 0x88, 0xB2, 0x1E],
@@ -416,7 +415,7 @@ impl ToString for ExtendedPubKey {
         }
         ret[13..45].copy_from_slice(&self.chain_code[..]);
         ret[45..78].copy_from_slice(&self.public_key.serialize()[..]);
-        base58::check_encode_slice(&ret[..])
+        fmt.write_str(&base58::check_encode_slice(&ret[..]))
     }
 }