From 6ab37bdca4e0f9a8172761683fb39e13d59222c7 Mon Sep 17 00:00:00 2001
From: Snezhkko <snezhkodaria38@gmail.com>
Date: Thu, 6 Nov 2025 22:56:19 +0200
Subject: [PATCH] feat: make BigUint::serialized_size allocation-free

---
 serialize/src/impls/int_like.rs | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/serialize/src/impls/int_like.rs b/serialize/src/impls/int_like.rs
index ec324e991..11000d752 100644
--- a/serialize/src/impls/int_like.rs
+++ b/serialize/src/impls/int_like.rs
@@ -210,8 +210,14 @@ impl CanonicalSerialize for BigUint {
     }
 
     #[inline]
-    fn serialized_size(&self, compress: Compress) -> usize {
-        self.to_bytes_le().serialized_size(compress)
+    fn serialized_size(&self, _compress: Compress) -> usize {
+        let bits = self.bits();
+        let byte_len = if bits == 0 {
+            1
+        } else {
+            ((bits + 7) / 8) as usize
+        };
+        8 + byte_len
     }
 }