From c2bf620b445f1cf7800adaab19571ef7150767f2 Mon Sep 17 00:00:00 2001
From: Alexander 'z33ky' Hirsch <1zeeky@gmail.com>
Date: Sat, 4 Mar 2023 16:04:20 +0100
Subject: [PATCH] argon2: provide std::error::Error::source() for Error

The Error type sometimes wraps other errors, which are now returned by
the source() method.
---
 argon2/src/error.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/argon2/src/error.rs b/argon2/src/error.rs
index f6f10e70..3a6b9646 100644
--- a/argon2/src/error.rs
+++ b/argon2/src/error.rs
@@ -121,4 +121,11 @@ impl From<Error> for password_hash::Error {
 }
 
 #[cfg(feature = "std")]
-impl std::error::Error for Error {}
+impl std::error::Error for Error {
+    fn source(&self) -> Option<&(dyn std::error::Error + 'static)> {
+        match self {
+            Self::B64Encoding(err) => Some(err),
+            _ => None,
+        }
+    }
+}