From 2473149eff9e560e721b3a74642da2240f059d4b Mon Sep 17 00:00:00 2001
From: "Sebastian R. Verschoor" <sebastian@zeroknowledge.me>
Date: Fri, 15 Jan 2021 16:27:58 -0500
Subject: [PATCH] Allow empty buffers for value zero in  methods

---
 src/biguint.rs   | 8 ++++++++
 tests/biguint.rs | 2 ++
 2 files changed, 10 insertions(+)

diff --git a/src/biguint.rs b/src/biguint.rs
index 432ff849..71778cb5 100644
--- a/src/biguint.rs
+++ b/src/biguint.rs
@@ -2423,6 +2423,10 @@ impl BigUint {
             "The radix must be within 2...256"
         );
 
+        if buf.is_empty() {
+            return Some(Zero::zero());
+        }
+
         if radix != 256 && buf.iter().any(|&b| b >= radix as u8) {
             return None;
         }
@@ -2466,6 +2470,10 @@ impl BigUint {
             "The radix must be within 2...256"
         );
 
+        if buf.is_empty() {
+            return Some(Zero::zero());
+        }
+
         if radix != 256 && buf.iter().any(|&b| b >= radix as u8) {
             return None;
         }
diff --git a/tests/biguint.rs b/tests/biguint.rs
index cc274954..3752c61d 100644
--- a/tests/biguint.rs
+++ b/tests/biguint.rs
@@ -1551,6 +1551,8 @@ fn test_from_and_to_radix() {
     }
 
     assert!(BigUint::from_radix_le(&[10, 100, 10], 50).is_none());
+    assert_eq!(BigUint::from_radix_le(&[], 2), Some(BigUint::zero()));
+    assert_eq!(BigUint::from_radix_be(&[], 2), Some(BigUint::zero()));
 }
 
 #[test]