From 1e83faf4f8234674674330c198f512c1a8cf74d6 Mon Sep 17 00:00:00 2001
From: Yuya Nishihara <yuya@tcha.org>
Date: Fri, 29 Mar 2024 19:48:13 +0900
Subject: [PATCH] tree: remove useless "Backend error" message from
 TreeMergeError

I don't think it adds any contextual information. TreeMergeError is somewhat
similar to BackendError.
---
 cli/tests/test_abandon_command.rs | 4 +---
 lib/src/tree.rs                   | 2 +-
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/cli/tests/test_abandon_command.rs b/cli/tests/test_abandon_command.rs
index 43f786178..ea510aa8b 100644
--- a/cli/tests/test_abandon_command.rs
+++ b/cli/tests/test_abandon_command.rs
@@ -317,9 +317,7 @@ fn test_bug_2600_rootcommit_special_case() {
     let stderr = test_env.jj_cmd_internal_error(&repo_path, &["abandon", "base"]);
     insta::assert_snapshot!(stderr, @r###"
     Internal error: Merge failed
-    Caused by:
-    1: Backend error
-    2: The Git backend does not support creating merge commits with the root commit as one of the parents.
+    Caused by: The Git backend does not support creating merge commits with the root commit as one of the parents.
     "###);
 }
 
diff --git a/lib/src/tree.rs b/lib/src/tree.rs
index 23690ff6a..e1b4c70a6 100644
--- a/lib/src/tree.rs
+++ b/lib/src/tree.rs
@@ -41,7 +41,7 @@ pub enum TreeMergeError {
         source: std::io::Error,
         file_id: FileId,
     },
-    #[error("Backend error")]
+    #[error(transparent)]
     BackendError(#[from] BackendError),
 }