Use peel_to_commit()

Author: jpgrayson

src/cmd/uncommit.rs

@@ -102,9 +102,8 @@ fn run(matches: &ArgMatches) -> Result<()> {
             .map_err(|_| anyhow!("Invalid committish `{committish}`"))?;
 
         let mut target_commit = target_object
-            .peel(git2::ObjectType::Commit).ok()
-            .and_then(|c| c.into_commit().ok())
-            .ok_or_else(|| anyhow!("Target `{committish}` cannot be evaluated as a commit"))?;
+            .peel_to_commit()
+            .map_err(|_| anyhow!("Target `{committish}` does not resolve to a commit"))?;
 
         let bases = repo.merge_bases(target_commit.id(), stack.base().id())?;
 

t/t1300-uncommit.sh

@@ -145,7 +145,7 @@ test_expect_success 'Uncommit when top != head' '
 
 test_expect_success 'Uncommit to something that does not resolve to a commit' '
     command_error stg uncommit --to HEAD^{tree} 2>err &&
-    grep -e "error: Target \`HEAD^{tree}\` cannot be evaluated as a commit" err
+    grep -e "error: Target \`HEAD^{tree}\` does not resolve to a commit" err
 '
 
 test_expect_success 'Uncommit to an annotated tag' '