From aa709556f9be5771c1f0ab373c36a5508061b7c7 Mon Sep 17 00:00:00 2001
From: "Daniel X. Pape" <dpape@dpape.com>
Date: Fri, 10 Jan 2025 17:44:32 -0800
Subject: [PATCH] Added warning about calling register_tags() when decoding

---
 src/ur_decodable.rs | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/ur_decodable.rs b/src/ur_decodable.rs
index b8cc688..d8496e9 100644
--- a/src/ur_decodable.rs
+++ b/src/ur_decodable.rs
@@ -7,8 +7,13 @@ use dcbor::CBORTaggedDecodable;
 /// A type that can be decoded from a UR.
 pub trait URDecodable: CBORTaggedDecodable {
     fn from_ur(ur: impl AsRef<UR>) -> Result<Self> where Self: Sized {
-        ur.as_ref().check_type(Self::cbor_tags()[0].name().as_ref().unwrap().clone())?;
-        Self::from_untagged_cbor(ur.as_ref().clone().into())
+        let tag = &Self::cbor_tags()[0];
+        if let Some(name) = tag.name().as_ref() {
+            ur.as_ref().check_type(name.clone())?;
+            Self::from_untagged_cbor(ur.as_ref().clone().into())
+        } else {
+            panic!("CBOR tag {} must have a name. Did you call `register_tags()`?", tag.value());
+        }
     }
 
     fn from_ur_string(ur_string: impl Into<String>) -> Result<Self> where Self: Sized {