From 29aead4a94a14b9a236d7268e2da2ff018a4a69a Mon Sep 17 00:00:00 2001
From: Matthias Beyer <mail@beyermatthias.de>
Date: Thu, 28 Apr 2022 12:46:50 +0200
Subject: [PATCH] Add Diagnostic::caused_by()

Signed-off-by: Matthias Beyer <mail@beyermatthias.de>
---
 src/protocol.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/protocol.rs b/src/protocol.rs
index 2a6545a..2493346 100644
--- a/src/protocol.rs
+++ b/src/protocol.rs
@@ -59,6 +59,11 @@ pub trait Diagnostic: std::error::Error {
     fn related<'a>(&'a self) -> Option<Box<dyn Iterator<Item = &'a dyn Diagnostic> + 'a>> {
         None
     }
+
+    /// The cause of the error.
+    fn caused_by(&self) -> Option<&dyn Diagnostic> {
+        None
+    }
 }
 
 impl std::error::Error for Box<dyn Diagnostic> {