cli: add a Ui::status() helper for writing non-error to stderr

This clarifies that status messages are not errors, and allows us to
implement a global `--quiet` flag for silencing status messages.

cli/examples/custom-command/main.rs

@@ -48,7 +48,7 @@ fn run_custom_command(
                 .write()?;
             tx.finish(ui, "Frobnicate")?;
             writeln!(
-                ui.stderr(),
+                ui.status(),
                 "Frobnicated revision: {}",
                 workspace_command.format_commit_summary(&new_commit)
             )?;

cli/src/cli_util.rs

@@ -327,7 +327,7 @@ impl CommandHelper {
                 repo_loader.op_store(),
                 |op_heads| {
                     writeln!(
-                        ui.stderr(),
+                        ui.status(),
                         "Concurrent modification detected, resolving automatically.",
                     )?;
                     let base_repo = repo_loader.load_at(&op_heads[0])?;
@@ -339,7 +339,7 @@ impl CommandHelper {
                         let num_rebased = tx.mut_repo().rebase_descendants(&self.settings)?;
                         if num_rebased > 0 {
                             writeln!(
-                                ui.stderr(),
+                                ui.status(),
                                 "Rebased {num_rebased} descendant commits onto commits rewritten \
                                  by other operation"
                             )?;
@@ -531,7 +531,7 @@ impl WorkspaceCommandHelper {
             locked_ws.finish(self.user_repo.repo.op_id().clone())?;
             if old_git_head.is_present() {
                 writeln!(
-                    ui.stderr(),
+                    ui.status(),
                     "Reset the working copy parent to the new Git HEAD."
                 )?;
             } else {
@@ -570,13 +570,13 @@ impl WorkspaceCommandHelper {
         let num_rebased = tx.mut_repo().rebase_descendants(&self.settings)?;
         if num_rebased > 0 {
             writeln!(
-                ui.stderr(),
+                ui.status(),
                 "Rebased {num_rebased} descendant commits off of commits rewritten from git"
             )?;
         }
         self.finish_transaction(ui, tx, "import git refs")?;
         writeln!(
-            ui.stderr(),
+            ui.status(),
             "Done importing changes from the underlying Git repo."
         )?;
         Ok(())
@@ -1117,7 +1117,7 @@ See https://github.com/martinvonz/jj/blob/main/docs/working-copy.md#stale-workin
             let num_rebased = mut_repo.rebase_descendants(&self.settings)?;
             if num_rebased > 0 {
                 writeln!(
-                    ui.stderr(),
+                    ui.status(),
                     "Rebased {num_rebased} descendant commits onto updated working copy"
                 )?;
             }
@@ -1147,7 +1147,7 @@ See https://github.com/martinvonz/jj/blob/main/docs/working-copy.md#stale-workin
             new_commit,
         )?;
         if Some(new_commit) != maybe_old_commit {
-            let mut formatter = ui.stderr_formatter();
+            let mut formatter = ui.status();
             let template = self.commit_summary_template();
             write!(formatter, "Working copy now at: ")?;
             formatter.with_label("working_copy", |fmt| template.format(new_commit, fmt))?;
@@ -1177,12 +1177,12 @@ See https://github.com/martinvonz/jj/blob/main/docs/working-copy.md#stale-workin
         description: impl Into<String>,
     ) -> Result<(), CommandError> {
         if !tx.mut_repo().has_changes() {
-            writeln!(ui.stderr(), "Nothing changed.")?;
+            writeln!(ui.status(), "Nothing changed.")?;
             return Ok(());
         }
         let num_rebased = tx.mut_repo().rebase_descendants(&self.settings)?;
         if num_rebased > 0 {
-            writeln!(ui.stderr(), "Rebased {num_rebased} descendant commits")?;
+            writeln!(ui.status(), "Rebased {num_rebased} descendant commits")?;
         }
 
         let old_repo = tx.base_repo().clone();
@@ -1279,7 +1279,7 @@ See https://github.com/martinvonz/jj/blob/main/docs/working-copy.md#stale-workin
             .retain(|change_id, _commits| !removed_conflicts_by_change_id.contains_key(change_id));
 
         // TODO: Also report new divergence and maybe resolved divergence
-        let mut fmt = ui.stderr_formatter();
+        let mut fmt = ui.status();
         let template = self.commit_summary_template();
         if !resolved_conflicts_by_change_id.is_empty() {
             writeln!(
@@ -1597,7 +1597,7 @@ pub fn print_checkout_stats(
 ) -> Result<(), std::io::Error> {
     if stats.added_files > 0 || stats.updated_files > 0 || stats.removed_files > 0 {
         writeln!(
-            ui.stderr(),
+            ui.status(),
             "Added {} files, modified {} files, removed {} files",
             stats.added_files,
             stats.updated_files,
@@ -1642,7 +1642,7 @@ pub fn print_trackable_remote_branches(ui: &Ui, view: &View) -> io::Result<()> {
         ui.hint_default(),
         "The following remote branches aren't associated with the existing local branches:"
     )?;
-    let mut formatter = ui.stderr_formatter();
+    let mut formatter = ui.status();
     for full_name in &remote_branch_names {
         write!(formatter, "  ")?;
         writeln!(formatter.labeled("branch"), "{full_name}")?;

cli/src/commands/abandon.rs

@@ -55,7 +55,7 @@ pub(crate) fn cmd_abandon(
         .evaluate_to_commits()?
         .try_collect()?;
     if to_abandon.is_empty() {
-        writeln!(ui.stderr(), "No revisions to abandon.")?;
+        writeln!(ui.status(), "No revisions to abandon.")?;
         return Ok(());
     }
     workspace_command.check_rewritable(&to_abandon)?;
@@ -67,12 +67,12 @@ pub(crate) fn cmd_abandon(
     let num_rebased = tx.mut_repo().rebase_descendants(command.settings())?;
 
     if to_abandon.len() == 1 {
-        write!(ui.stderr(), "Abandoned commit ")?;
+        write!(ui.status(), "Abandoned commit ")?;
         tx.base_workspace_helper()
-            .write_commit_summary(ui.stderr_formatter().as_mut(), &to_abandon[0])?;
+            .write_commit_summary(ui.status().as_mut(), &to_abandon[0])?;
-        writeln!(ui.stderr())?;
+        writeln!(ui.status())?;
     } else if !args.summary {
-        let mut formatter = ui.stderr_formatter();
+        let mut formatter = ui.status();
         let template = tx.base_workspace_helper().commit_summary_template();
         writeln!(formatter, "Abandoned the following commits:")?;
         for commit in &to_abandon {
@@ -81,11 +81,11 @@ pub(crate) fn cmd_abandon(
             writeln!(formatter)?;
         }
     } else {
-        writeln!(ui.stderr(), "Abandoned {} commits.", &to_abandon.len())?;
+        writeln!(ui.status(), "Abandoned {} commits.", &to_abandon.len())?;
     }
     if num_rebased > 0 {
         writeln!(
-            ui.stderr(),
+            ui.status(),
             "Rebased {num_rebased} descendant commits onto parents of abandoned commits"
         )?;
     }

cli/src/commands/bench.rs

@@ -116,7 +116,7 @@ where
     let result = routine();
     let after = Instant::now();
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "First run took {:?} and produced: {:?}",
         after.duration_since(before),
         result
@@ -203,7 +203,7 @@ fn bench_revset<M: Measurement>(
     group: &mut BenchmarkGroup<M>,
     revset: &str,
 ) -> Result<(), CommandError> {
-    writeln!(ui.stderr(), "----------Testing revset: {revset}----------")?;
+    writeln!(ui.status(), "----------Testing revset: {revset}----------")?;
     let expression = revset::optimize(workspace_command.parse_revset(revset)?.expression().clone());
     // Time both evaluation and iteration.
     let routine = |workspace_command: &WorkspaceCommandHelper, expression: Rc<RevsetExpression>| {
@@ -220,7 +220,7 @@ fn bench_revset<M: Measurement>(
     let result = routine(workspace_command, expression.clone());
     let after = Instant::now();
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "First run took {:?} and produced {result} commits",
         after.duration_since(before),
     )?;

cli/src/commands/branch.rs

@@ -497,7 +497,7 @@ fn cmd_branch_delete(
     }
     tx.finish(ui, format!("delete {}", make_branch_term(&names)))?;
     if names.len() > 1 {
-        writeln!(ui.stderr(), "Deleted {} branches.", names.len())?;
+        writeln!(ui.status(), "Deleted {} branches.", names.len())?;
     }
     Ok(())
 }
@@ -523,7 +523,7 @@ fn cmd_branch_forget(
     }
     tx.finish(ui, format!("forget {}", make_branch_term(&names)))?;
     if names.len() > 1 {
-        writeln!(ui.stderr(), "Forgot {} branches.", names.len())?;
+        writeln!(ui.status(), "Forgot {} branches.", names.len())?;
     }
     Ok(())
 }
@@ -554,7 +554,7 @@ fn cmd_branch_track(
     tx.finish(ui, format!("track remote {}", make_branch_term(&names)))?;
     if names.len() > 1 {
         writeln!(
-            ui.stderr(),
+            ui.status(),
             "Started tracking {} remote branches.",
             names.len()
         )?;
@@ -594,7 +594,7 @@ fn cmd_branch_untrack(
     tx.finish(ui, format!("untrack remote {}", make_branch_term(&names)))?;
     if names.len() > 1 {
         writeln!(
-            ui.stderr(),
+            ui.status(),
             "Stopped tracking {} remote branches.",
             names.len()
         )?;

cli/src/commands/debug.rs

@@ -259,7 +259,7 @@ fn cmd_debug_reindex(
             .build_index_at_operation(&op, repo_loader.store())
             .map_err(internal_error)?;
         writeln!(
-            ui.stderr(),
+            ui.status(),
             "Finished indexing {:?} commits.",
             default_index.as_composite().stats().num_commits
         )?;
@@ -358,7 +358,7 @@ fn cmd_debug_watchman(
             };
             locked_local_wc.reset_watchman()?;
             locked_ws.finish(repo.op_id().clone())?;
-            writeln!(ui.stderr(), "Reset Watchman clock")?;
+            writeln!(ui.status(), "Reset Watchman clock")?;
         }
     }
     Ok(())

cli/src/commands/describe.rs

@@ -83,7 +83,7 @@ pub(crate) fn cmd_describe(
         edit_description(workspace_command.repo(), &template, command.settings())?
     };
     if description == *commit.description() && !args.reset_author {
-        writeln!(ui.stderr(), "Nothing changed.")?;
+        writeln!(ui.status(), "Nothing changed.")?;
     } else {
         let mut tx = workspace_command.start_transaction();
         let mut commit_builder = tx

cli/src/commands/diffedit.rs

@@ -97,7 +97,7 @@ don't make any changes, then the operation will be aborted.",
     let tree = target_commit.tree()?;
     let tree_id = diff_editor.edit(&base_tree, &tree, &EverythingMatcher, Some(&instructions))?;
     if tree_id == *target_commit.tree_id() {
-        writeln!(ui.stderr(), "Nothing changed.")?;
+        writeln!(ui.status(), "Nothing changed.")?;
     } else {
         let mut_repo = tx.mut_repo();
         let new_commit = mut_repo
@@ -107,11 +107,11 @@ don't make any changes, then the operation will be aborted.",
         // rebase_descendants early; otherwise `new_commit` would always have
         // a conflicted change id at this point.
         let num_rebased = tx.mut_repo().rebase_descendants(command.settings())?;
-        write!(ui.stderr(), "Created ")?;
+        write!(ui.status(), "Created ")?;
-        tx.write_commit_summary(ui.stderr_formatter().as_mut(), &new_commit)?;
+        tx.write_commit_summary(ui.status().as_mut(), &new_commit)?;
-        writeln!(ui.stderr())?;
+        writeln!(ui.status())?;
         if num_rebased > 0 {
-            writeln!(ui.stderr(), "Rebased {num_rebased} descendant commits")?;
+            writeln!(ui.status(), "Rebased {num_rebased} descendant commits")?;
         }
         tx.finish(ui, format!("edit commit {}", target_commit.id().hex()))?;
     }

cli/src/commands/duplicate.rs

@@ -47,7 +47,7 @@ pub(crate) fn cmd_duplicate(
         .evaluate_to_commit_ids()?
         .collect(); // in reverse topological order
     if to_duplicate.is_empty() {
-        writeln!(ui.stderr(), "No revisions to duplicate.")?;
+        writeln!(ui.status(), "No revisions to duplicate.")?;
         return Ok(());
     }
     if to_duplicate.last() == Some(workspace_command.repo().store().root_commit_id()) {
@@ -78,9 +78,9 @@ pub(crate) fn cmd_duplicate(
     }
 
     for (old_id, new_commit) in &duplicated_old_to_new {
-        write!(ui.stderr(), "Duplicated {} as ", short_commit_hash(old_id))?;
+        write!(ui.status(), "Duplicated {} as ", short_commit_hash(old_id))?;
-        tx.write_commit_summary(ui.stderr_formatter().as_mut(), new_commit)?;
+        tx.write_commit_summary(ui.status().as_mut(), new_commit)?;
-        writeln!(ui.stderr())?;
+        writeln!(ui.status())?;
     }
     tx.finish(ui, format!("duplicate {} commit(s)", to_duplicate.len()))?;
     Ok(())

cli/src/commands/edit.rs

@@ -46,7 +46,7 @@ pub(crate) fn cmd_edit(
     let new_commit = workspace_command.resolve_single_rev(&args.revision)?;
     workspace_command.check_rewritable([&new_commit])?;
     if workspace_command.get_wc_commit_id() == Some(new_commit.id()) {
-        writeln!(ui.stderr(), "Already editing that commit")?;
+        writeln!(ui.status(), "Already editing that commit")?;
     } else {
         let mut tx = workspace_command.start_transaction();
         tx.edit(&new_commit)?;

cli/src/commands/git.rs

@@ -482,7 +482,7 @@ fn init_git_refs(
     }
     let repo = tx.commit("import git refs");
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "Done importing changes from the underlying Git repo."
     )?;
     Ok(repo)
@@ -509,7 +509,7 @@ fn cmd_git_init(
 
     let relative_wc_path = file_util::relative_path(cwd, &wc_path);
     writeln!(
-        ui.stderr(),
+        ui.status(),
         r#"Initialized repo in "{}""#,
         relative_wc_path.display()
     )?;
@@ -747,7 +747,7 @@ fn do_git_clone(
     };
     let git_repo = get_git_repo(repo.store())?;
     writeln!(
-        ui.stderr(),
+        ui.status(),
         r#"Fetching into new repo in "{}""#,
         wc_path.display()
     )?;
@@ -857,7 +857,7 @@ fn cmd_git_push(
             match classify_branch_update(branch_name, &remote, targets) {
                 Ok(Some(update)) => branch_updates.push((branch_name.to_owned(), update)),
                 Ok(None) => writeln!(
-                    ui.stderr(),
+                    ui.status(),
                     "Branch {branch_name}@{remote} already matches {branch_name}",
                 )?,
                 Err(reason) => return Err(reason.into()),
@@ -896,7 +896,7 @@ fn cmd_git_push(
         );
     }
     if branch_updates.is_empty() {
-        writeln!(ui.stderr(), "Nothing changed.")?;
+        writeln!(ui.status(), "Nothing changed.")?;
         return Ok(());
     }
 
@@ -958,20 +958,20 @@ fn cmd_git_push(
         }
     }
 
-    writeln!(ui.stderr(), "Branch changes to push to {}:", &remote)?;
+    writeln!(ui.status(), "Branch changes to push to {}:", &remote)?;
     for (branch_name, update) in &branch_updates {
         match (&update.old_target, &update.new_target) {
             (Some(old_target), Some(new_target)) => {
                 if force_pushed_branches.contains(branch_name) {
                     writeln!(
-                        ui.stderr(),
+                        ui.status(),
                         "  Force branch {branch_name} from {} to {}",
                         short_commit_hash(old_target),
                         short_commit_hash(new_target)
                     )?;
                 } else {
                     writeln!(
-                        ui.stderr(),
+                        ui.status(),
                         "  Move branch {branch_name} from {} to {}",
                         short_commit_hash(old_target),
                         short_commit_hash(new_target)
@@ -980,14 +980,14 @@ fn cmd_git_push(
             }
             (Some(old_target), None) => {
                 writeln!(
-                    ui.stderr(),
+                    ui.status(),
                     "  Delete branch {branch_name} from {}",
                     short_commit_hash(old_target)
                 )?;
             }
             (None, Some(new_target)) => {
                 writeln!(
-                    ui.stderr(),
+                    ui.status(),
                     "  Add branch {branch_name} to {}",
                     short_commit_hash(new_target)
                 )?;
@@ -999,7 +999,7 @@ fn cmd_git_push(
     }
 
     if args.dry_run {
-        writeln!(ui.stderr(), "Dry-run requested, not pushing.")?;
+        writeln!(ui.status(), "Dry-run requested, not pushing.")?;
         return Ok(());
     }
 
@@ -1129,7 +1129,7 @@ fn update_change_branches(
         }
         if view.get_local_branch(&branch_name).is_absent() {
             writeln!(
-                ui.stderr(),
+                ui.status(),
                 "Creating branch {} for revision {}",
                 branch_name,
                 change_str.deref()
@@ -1268,7 +1268,7 @@ fn cmd_git_submodule_print_gitmodules(
     let gitmodules_path = RepoPath::from_internal_string(".gitmodules");
     let mut gitmodules_file = match tree.path_value(gitmodules_path).into_resolved() {
         Ok(None) => {
-            writeln!(ui.stderr(), "No submodules!")?;
+            writeln!(ui.status(), "No submodules!")?;
             return Ok(());
         }
         Ok(Some(TreeValue::File { id, .. })) => repo.store().read_file(gitmodules_path, &id)?,

cli/src/commands/init.rs

@@ -79,7 +79,7 @@ Set `ui.allow-init-native` to allow initializing a repo with the native backend.
 
     let relative_wc_path = file_util::relative_path(cwd, &wc_path);
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "Initialized repo in \"{}\"",
         relative_wc_path.display()
     )?;

cli/src/commands/new.rs

@@ -189,15 +189,15 @@ Please use `jj new 'all:x|y'` instead of `jj new --allow-large-revsets x y`.",
     }
     num_rebased += tx.mut_repo().rebase_descendants(command.settings())?;
     if args.no_edit {
-        write!(ui.stderr(), "Created new commit ")?;
+        write!(ui.status(), "Created new commit ")?;
-        tx.write_commit_summary(ui.stderr_formatter().as_mut(), &new_commit)?;
+        tx.write_commit_summary(ui.status().as_mut(), &new_commit)?;
-        writeln!(ui.stderr())?;
+        writeln!(ui.status())?;
     } else {
         tx.edit(&new_commit).unwrap();
         // The description of the new commit will be printed by tx.finish()
     }
     if num_rebased > 0 {
-        writeln!(ui.stderr(), "Rebased {num_rebased} descendant commits")?;
+        writeln!(ui.status(), "Rebased {num_rebased} descendant commits")?;
     }
     tx.finish(ui, "new empty commit")?;
     Ok(())

cli/src/commands/operation.rs

@@ -364,11 +364,11 @@ fn cmd_op_abandon(
     )?;
     let [new_head_id]: [OperationId; 1] = stats.new_head_ids.try_into().unwrap();
     if current_head_op.id() == &new_head_id {
-        writeln!(ui.stderr(), "Nothing changed.")?;
+        writeln!(ui.status(), "Nothing changed.")?;
         return Ok(());
     }
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "Abandoned {} operations and reparented {} descendant operations.",
         stats.unreachable_count,
         stats.rewritten_count,

cli/src/commands/rebase.rs

@@ -318,7 +318,7 @@ fn rebase_descendants(
     let num_rebased = old_commits.len()
         + tx.mut_repo()
             .rebase_descendants_with_options(settings, rebase_options)?;
-    writeln!(ui.stderr(), "Rebased {num_rebased} commits")?;
+    writeln!(ui.status(), "Rebased {num_rebased} commits")?;
     let tx_message = if old_commits.len() == 1 {
         format!(
             "rebase commit {} and descendants",
@@ -447,9 +447,9 @@ fn rebase_revision(
     // longer have any children; they have all been rebased and the originals
     // have been abandoned.
     let skipped_commit_rebase = if old_commit.parents() == new_parents {
-        write!(ui.stderr(), "Skipping rebase of commit ")?;
+        write!(ui.status(), "Skipping rebase of commit ")?;
-        tx.write_commit_summary(ui.stderr_formatter().as_mut(), &old_commit)?;
+        tx.write_commit_summary(ui.status().as_mut(), &old_commit)?;
-        writeln!(ui.stderr())?;
+        writeln!(ui.status())?;
         true
     } else {
         rebase_commit(settings, tx.mut_repo(), &old_commit, &new_parents)?;
@@ -460,12 +460,12 @@ fn rebase_revision(
     if num_rebased_descendants > 0 {
         if skipped_commit_rebase {
             writeln!(
-                ui.stderr(),
+                ui.status(),
                 "Rebased {num_rebased_descendants} descendant commits onto parent of commit"
             )?;
         } else {
             writeln!(
-                ui.stderr(),
+                ui.status(),
                 "Also rebased {num_rebased_descendants} descendant commits onto parent of rebased \
                  commit"
             )?;
@@ -500,7 +500,7 @@ fn log_skipped_rebase_commits_message(
     workspace_command: &WorkspaceCommandHelper,
     commits: &[&Commit],
 ) -> Result<(), CommandError> {
-    let mut fmt = ui.stderr_formatter();
+    let mut fmt = ui.status();
     let template = workspace_command.commit_summary_template();
     if commits.len() == 1 {
         write!(fmt, "Skipping rebase of commit ")?;

cli/src/commands/resolve.rs

@@ -99,7 +99,7 @@ pub(crate) fn cmd_resolve(
     workspace_command.check_rewritable([&commit])?;
     let merge_editor = workspace_command.merge_editor(ui, args.tool.as_deref())?;
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "Resolving conflicts in: {}",
         workspace_command.format_file_path(repo_path)
     )?;
@@ -120,14 +120,10 @@ pub(crate) fn cmd_resolve(
         let new_conflicts = new_tree.conflicts().collect_vec();
         if !new_conflicts.is_empty() {
             writeln!(
-                ui.stderr(),
+                ui.status(),
                 "After this operation, some files at this revision still have conflicts:"
             )?;
-            print_conflicted_paths(
+            print_conflicted_paths(&new_conflicts, ui.status().as_mut(), &workspace_command)?;
-                &new_conflicts,
-                ui.stderr_formatter().as_mut(),
-                &workspace_command,
-            )?;
         }
     };
     Ok(())

cli/src/commands/restore.rs

@@ -101,7 +101,7 @@ pub(crate) fn cmd_restore(
     let to_tree = to_commit.tree()?;
     let new_tree_id = restore_tree(&from_tree, &to_tree, matcher.as_ref())?;
     if &new_tree_id == to_commit.tree_id() {
-        writeln!(ui.stderr(), "Nothing changed.")?;
+        writeln!(ui.status(), "Nothing changed.")?;
     } else {
         let mut tx = workspace_command.start_transaction();
         let mut_repo = tx.mut_repo();
@@ -112,11 +112,11 @@ pub(crate) fn cmd_restore(
         // rebase_descendants early; otherwise `new_commit` would always have
         // a conflicted change id at this point.
         let num_rebased = tx.mut_repo().rebase_descendants(command.settings())?;
-        write!(ui.stderr(), "Created ")?;
+        write!(ui.status(), "Created ")?;
-        tx.write_commit_summary(ui.stderr_formatter().as_mut(), &new_commit)?;
+        tx.write_commit_summary(ui.status().as_mut(), &new_commit)?;
-        writeln!(ui.stderr())?;
+        writeln!(ui.status())?;
         if num_rebased > 0 {
-            writeln!(ui.stderr(), "Rebased {num_rebased} descendant commits")?;
+            writeln!(ui.status(), "Rebased {num_rebased} descendant commits")?;
         }
         tx.finish(ui, format!("restore into commit {}", to_commit.id().hex()))?;
     }

cli/src/commands/split.rs

@@ -88,7 +88,7 @@ don't make any changes, then the operation will be aborted.
         diff_selector.select(&base_tree, &end_tree, matcher.as_ref(), Some(&instructions))?;
     if &selected_tree_id == commit.tree_id() && diff_selector.is_interactive() {
         // The user selected everything from the original commit.
-        writeln!(ui.stderr(), "Nothing changed.")?;
+        writeln!(ui.status(), "Nothing changed.")?;
         return Ok(());
     }
     if selected_tree_id == base_tree.id() {
@@ -150,13 +150,13 @@ don't make any changes, then the operation will be aborted.
         .set_rewritten_commit(commit.id().clone(), second_commit.id().clone());
     let num_rebased = tx.mut_repo().rebase_descendants(command.settings())?;
     if num_rebased > 0 {
-        writeln!(ui.stderr(), "Rebased {num_rebased} descendant commits")?;
+        writeln!(ui.status(), "Rebased {num_rebased} descendant commits")?;
     }
-    write!(ui.stderr(), "First part: ")?;
+    write!(ui.status(), "First part: ")?;
-    tx.write_commit_summary(ui.stderr_formatter().as_mut(), &first_commit)?;
+    tx.write_commit_summary(ui.status().as_mut(), &first_commit)?;
-    write!(ui.stderr(), "\nSecond part: ")?;
+    write!(ui.status(), "\nSecond part: ")?;
-    tx.write_commit_summary(ui.stderr_formatter().as_mut(), &second_commit)?;
+    tx.write_commit_summary(ui.status().as_mut(), &second_commit)?;
-    writeln!(ui.stderr())?;
+    writeln!(ui.status())?;
     tx.finish(ui, format!("split commit {}", commit.id().hex()))?;
     Ok(())
 }

cli/src/commands/untrack.rs

@@ -100,7 +100,7 @@ Make sure they're ignored, then try again.",
     }
     let num_rebased = tx.mut_repo().rebase_descendants(command.settings())?;
     if num_rebased > 0 {
-        writeln!(ui.stderr(), "Rebased {num_rebased} descendant commits")?;
+        writeln!(ui.status(), "Rebased {num_rebased} descendant commits")?;
     }
     let repo = tx.commit("untrack paths");
     locked_ws.finish(repo.op_id().clone())?;

cli/src/commands/workspace.rs

@@ -166,7 +166,7 @@ fn cmd_workspace_add(
         workspace_id,
     )?;
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "Created workspace in \"{}\"",
         file_util::relative_path(old_workspace_command.workspace_root(), &destination_path)
             .display()
@@ -329,7 +329,7 @@ fn create_and_check_out_recovery_commit(
     locked_workspace.finish(repo.op_id().clone())?;
 
     writeln!(
-        ui.stderr(),
+        ui.status(),
         "Created and checked out recovery commit {}",
         short_commit_hash(new_commit.id())
     )?;
@@ -357,7 +357,7 @@ fn for_stale_working_copy(
             ),
             Err(e @ OpStoreError::ObjectNotFound { .. }) => {
                 writeln!(
-                    ui.stderr(),
+                    ui.status(),
                     "Failed to read working copy's current operation; attempting recovery. Error \
                      message from read attempt: {e}"
                 )?;
@@ -401,7 +401,7 @@ fn cmd_workspace_update_stale(
     match check_stale_working_copy(locked_ws.locked_wc(), &desired_wc_commit, &repo)? {
         WorkingCopyFreshness::Fresh | WorkingCopyFreshness::Updated(_) => {
             writeln!(
-                ui.stderr(),
+                ui.status(),
                 "Nothing to do (the working copy is not stale)."
             )?;
         }
@@ -424,11 +424,11 @@ fn cmd_workspace_update_stale(
                     )
                 })?;
             locked_ws.finish(repo.op_id().clone())?;
-            write!(ui.stderr(), "Working copy now at: ")?;
+            write!(ui.status(), "Working copy now at: ")?;
-            ui.stderr_formatter().with_label("working_copy", |fmt| {
+            ui.status().with_label("working_copy", |fmt| {
                 workspace_command.write_commit_summary(fmt, &desired_wc_commit)
             })?;
-            writeln!(ui.stderr())?;
+            writeln!(ui.status())?;
             print_checkout_stats(ui, stats, &desired_wc_commit)?;
         }
     }

cli/src/git_util.rs

@@ -192,7 +192,7 @@ impl GitSidebandProgressMessageWriter {
             }
             self.scratch.extend_from_slice(&progress_message[i..i + 1]);
 
-            ui.stderr().write_all(&self.scratch)?;
+            ui.status().write_all(&self.scratch)?;
             self.scratch.clear();
 
             index = i + 1;
@@ -212,7 +212,7 @@ impl GitSidebandProgressMessageWriter {
     pub fn flush(&mut self, ui: &Ui) -> std::io::Result<()> {
         if !self.scratch.is_empty() {
             self.scratch.push(b'\n');
-            ui.stderr().write_all(&self.scratch)?;
+            ui.status().write_all(&self.scratch)?;
             self.scratch.clear();
         }
 
@@ -274,16 +274,16 @@ pub fn print_git_import_stats(
 
         let max_width = refs_stats.iter().map(|x| x.ref_name.width()).max();
         if let Some(max_width) = max_width {
-            let mut stderr = ui.stderr_formatter();
+            let mut formatter = ui.status();
             for status in refs_stats {
-                status.output(max_width, has_both_ref_kinds, &mut *stderr)?;
+                status.output(max_width, has_both_ref_kinds, &mut *formatter)?;
             }
         }
     }
 
     if !stats.abandoned_commits.is_empty() {
         writeln!(
-            ui.stderr(),
+            ui.status(),
             "Abandoned {} commits that are no longer reachable.",
             stats.abandoned_commits.len()
         )?;

cli/src/ui.rs

@@ -373,6 +373,12 @@ impl Ui {
         })
     }
 
+    /// Writes a message that's a status update not part of the command's main
+    /// output.
+    pub fn status(&self) -> Box<dyn Formatter + '_> {
+        self.stderr_formatter()
+    }
+
     /// Writer to print hint with the default "Hint: " heading.
     pub fn hint_default(
         &self,
@@ -382,7 +388,7 @@ impl Ui {
 
     /// Writer to print hint without the "Hint: " heading.
     pub fn hint_no_heading(&self) -> LabeledWriter<Box<dyn Formatter + '_>, &'static str> {
-        LabeledWriter::new(self.stderr_formatter(), "hint")
+        LabeledWriter::new(self.status(), "hint")
     }
 
     /// Writer to print hint with the given heading.
@@ -390,7 +396,7 @@ impl Ui {
         &self,
         heading: H,
     ) -> HeadingLabeledWriter<Box<dyn Formatter + '_>, &'static str, H> {
-        HeadingLabeledWriter::new(self.stderr_formatter(), "hint", heading)
+        HeadingLabeledWriter::new(self.status(), "hint", heading)
     }
 
     /// Writer to print warning with the default "Warning: " heading.