Improve short_commit_description for commits without a description

src/cli_util.rs

@@ -1395,9 +1395,19 @@ pub fn run_ui_editor(settings: &UserSettings, edit_path: &PathBuf) -> Result<(),
     Ok(())
 }
 
+// TODO: Consider basing this function on `write_commit_summary`. It will need
+// more arguments passed to it, but the output will be more consistent.
 pub fn short_commit_description(commit: &Commit) -> String {
     let first_line = commit.description().split('\n').next().unwrap();
-    format!("{} ({})", short_commit_hash(commit.id()), first_line)
+    format!(
+        "{} ({})",
+        short_commit_hash(commit.id()),
+        if first_line.is_empty() {
+            "no description set"
+        } else {
+            first_line
+        }
+    )
 }
 
 pub fn short_commit_hash(commit_id: &CommitId) -> String {

tests/test_checkout.rs

@@ -66,7 +66,7 @@ fn test_checkout_not_single_rev() {
     insta::assert_snapshot!(stderr, @r###"
     Error: Revset "root..@" resolved to more than one revision
     Hint: The revset resolved to these revisions:
-    2f8593712db5 ()
+    2f8593712db5 (no description set)
     5c1afd8b074f (fifth)
     009f88bf7141 (fourth)
     3fa8931e7b89 (third)