From 9be85406e8ef1f01c2a2a3f1de1a0ac15b02f784 Mon Sep 17 00:00:00 2001
From: Boyu Yang <yangby@cryptape.com>
Date: Mon, 11 Jun 2018 22:50:26 +0800
Subject: [PATCH] Prefix '0x' for lower hex with alternate flag.

---
 fixed-hash/src/hash.rs  | 6 ++++--
 tests/src/hash_tests.rs | 1 +
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/fixed-hash/src/hash.rs b/fixed-hash/src/hash.rs
index 1d67bed..682a528 100644
--- a/fixed-hash/src/hash.rs
+++ b/fixed-hash/src/hash.rs
@@ -133,8 +133,7 @@ macro_rules! construct_hash {
 
 		impl ::core::fmt::Debug for $from {
 			fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
-				write!(f, "0x")?;
-				::core::fmt::LowerHex::fmt(self, f)
+				write!(f, "{:#x}", self)
 			}
 		}
 
@@ -154,6 +153,9 @@ macro_rules! construct_hash {
 
 		impl ::core::fmt::LowerHex for $from {
 			fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
+				if f.alternate() {
+					write!(f, "0x");
+				}
 				for i in &self.0[..] {
 					write!(f, "{:02x}", i)?;
 				}
diff --git a/tests/src/hash_tests.rs b/tests/src/hash_tests.rs
index cb3174e..b21b560 100644
--- a/tests/src/hash_tests.rs
+++ b/tests/src/hash_tests.rs
@@ -7,6 +7,7 @@ fn should_format_and_debug_correctly() {
         assert_eq!(format!("{}", hash), format!("0x{}", display));
         assert_eq!(format!("{:?}", hash), format!("0x{}", hex));
         assert_eq!(format!("{:x}", hash), hex);
+        assert_eq!(format!("{:#x}", hash), format!("0x{}", hex));
     };
 
     test(0x1, "00000000000000000000000000000001", "0000…0001");