From 4284deed29114c5e31ef7c29e28e352b860f74e7 Mon Sep 17 00:00:00 2001
From: vicjuma <vicjuma945@gmail.com>
Date: Sat, 14 Jun 2025 01:42:01 +0300
Subject: [PATCH] DerivationPath: support 'h' in Display output for hardened
 components
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Aligns with ChildNumber’s format and improves consistency when debugging or comparing derivation paths.

Resolves: #4618
---
 bitcoin/src/bip32.rs | 19 +++++++++++++++++--
 1 file changed, 17 insertions(+), 2 deletions(-)

diff --git a/bitcoin/src/bip32.rs b/bitcoin/src/bip32.rs
index c1bff9170..08466e3c8 100644
--- a/bitcoin/src/bip32.rs
+++ b/bitcoin/src/bip32.rs
@@ -482,11 +482,19 @@ impl fmt::Display for DerivationPath {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         let mut iter = self.0.iter();
         if let Some(first_element) = iter.next() {
-            write!(f, "{}", first_element)?;
+            if f.alternate() {
+                write!(f, "{:#}", first_element)?;
+            } else {
+                write!(f, "{}", first_element)?;
+            }
         }
         for cn in iter {
             f.write_str("/")?;
-            write!(f, "{}", cn)?;
+            if f.alternate() {
+                write!(f, "{:#}", cn)?;
+            } else {
+                write!(f, "{}", cn)?;
+            }
         }
         Ok(())
     }
@@ -1108,6 +1116,13 @@ mod tests {
         }
     }
 
+    #[test]
+    fn test_derivation_path_display() {
+        let path = DerivationPath::from_str("m/84'/0'/0'/0/0").unwrap();
+        assert_eq!(format!("{}", path), "84'/0'/0'/0/0");
+        assert_eq!(format!("{:#}", path), "84h/0h/0h/0/0");
+    }
+
     #[test]
     fn parse_derivation_path_out_of_range() {
         let invalid_path = "2147483648";