From d38cf51c63061cfe44d67bd1bf93694c8a89b41e Mon Sep 17 00:00:00 2001
From: Robert Hensing <robert@roberthensing.nl>
Date: Wed, 10 Apr 2024 14:24:01 +0200
Subject: [PATCH] feat: Context.is_key_error

(cherry picked from commit f754e243852103164dbc6fdaf8c0cccb3c85cfb1)
---
 rust/nix-util/src/context.rs | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/rust/nix-util/src/context.rs b/rust/nix-util/src/context.rs
index 772511e..73540ca 100644
--- a/rust/nix-util/src/context.rs
+++ b/rust/nix-util/src/context.rs
@@ -34,6 +34,10 @@ impl Context {
         }
         Ok(())
     }
+    /// NIX_ERR_KEY is returned when e.g. an attribute is missing. Return true if the error is of this type.
+    pub fn is_key_error(&self) -> bool {
+        unsafe { raw::err_code(self.inner.as_ptr()) == raw::NIX_ERR_KEY }
+    }
 }
 
 impl Drop for Context {