cli: highlight "Warning: " and "warning: " headings

cli/src/cli_util.rs

@@ -1210,7 +1210,7 @@ See https://github.com/martinvonz/jj/blob/main/docs/working-copy.md#stale-workin
         let settings = &self.settings;
         if settings.user_name().is_empty() || settings.user_email().is_empty() {
             writeln!(
-                ui.warning(),
+                ui.warning_no_heading(),
                 r#"Name and email not configured. Until configured, your commits will be created with the empty identity, and can't be pushed to remotes. To configure, run:
   jj config set --user user.name "Some One"
   jj config set --user user.email "someone@example.com""#
@@ -1596,7 +1596,7 @@ pub fn print_checkout_stats(
     }
     if stats.skipped_files != 0 {
         writeln!(
-            ui.warning(),
+            ui.warning_no_heading(),
             "{} of those updates were skipped because there were conflicting changes in the \
              working copy.",
             stats.skipped_files
@@ -1739,7 +1739,10 @@ fn load_template_aliases(
                 .map_err(|e| e.to_string())
                 .and_then(|v| aliases_map.insert(&decl, v).map_err(|e| e.to_string()));
             if let Err(s) = r {
-                writeln!(ui.warning(), r#"Failed to load "{TABLE_KEY}.{decl}": {s}"#)?;
+                writeln!(
+                    ui.warning_no_heading(),
+                    r#"Failed to load "{TABLE_KEY}.{decl}": {s}"#
+                )?;
             }
         }
     }
@@ -2549,7 +2552,7 @@ impl CliRunner {
             let new_string_args = expand_args(ui, &self.app, env::args_os(), &config).ok();
             if new_string_args.as_ref() != Some(&string_args) {
                 writeln!(
-                    ui.warning(),
+                    ui.warning_no_heading(),
                     "Command aliases cannot be loaded from -R/--repository path"
                 )?;
             }

cli/src/commands/branch.rs

@@ -258,8 +258,8 @@ fn cmd_branch_create(
 
     if branch_names.len() > 1 {
         writeln!(
-            ui.warning(),
-            "warning: Creating multiple branches: {}",
+            ui.warning_with_heading("warning: "),
+            "Creating multiple branches: {}",
             branch_names.join(", "),
         )?;
     }
@@ -321,8 +321,8 @@ fn cmd_branch_rename(
         .any(|(_, remote_ref)| remote_ref.is_tracking())
     {
         writeln!(
-            ui.warning(),
-            "Warning: Branch {old_branch} has tracking remote branches which were not renamed."
+            ui.warning_with_heading("Warning: "),
+            "Branch {old_branch} has tracking remote branches which were not renamed."
         )?;
         writeln!(
             ui.hint_with_heading("Hint: "),
@@ -370,8 +370,8 @@ fn cmd_branch_set(
 
     if branch_names.len() > 1 {
         writeln!(
-            ui.warning(),
-            "warning: Updating multiple branches: {}",
+            ui.warning_with_heading("warning: "),
+            "Updating multiple branches: {}",
             branch_names.join(", "),
         )?;
     }
@@ -487,7 +487,7 @@ fn cmd_branch_delete(
     let view = workspace_command.repo().view();
     if !args.glob.is_empty() {
         writeln!(
-            ui.warning(),
+            ui.warning_no_heading(),
             "--glob has been deprecated. Please prefix the pattern with `glob:` instead."
         )?;
     }
@@ -514,7 +514,7 @@ fn cmd_branch_forget(
     let view = workspace_command.repo().view();
     if !args.glob.is_empty() {
         writeln!(
-            ui.warning(),
+            ui.warning_no_heading(),
             "--glob has been deprecated. Please prefix the pattern with `glob:` instead."
         )?;
     }
@@ -541,7 +541,10 @@ fn cmd_branch_track(
     let mut names = Vec::new();
     for (name, remote_ref) in find_remote_branches(view, &args.names)? {
         if remote_ref.is_tracking() {
-            writeln!(ui.warning(), "Remote branch already tracked: {name}")?;
+            writeln!(
+                ui.warning_no_heading(),
+                "Remote branch already tracked: {name}"
+            )?;
         } else {
             names.push(name);
         }
@@ -574,11 +577,14 @@ fn cmd_branch_untrack(
         if name.remote == git::REMOTE_NAME_FOR_LOCAL_GIT_REPO {
             // This restriction can be lifted if we want to support untracked @git branches.
             writeln!(
-                ui.warning(),
+                ui.warning_no_heading(),
                 "Git-tracking branch cannot be untracked: {name}"
             )?;
         } else if !remote_ref.is_tracking() {
-            writeln!(ui.warning(), "Remote branch not tracked yet: {name}")?;
+            writeln!(
+                ui.warning_no_heading(),
+                "Remote branch not tracked yet: {name}"
+            )?;
         } else {
             names.push(name);
         }

cli/src/commands/checkout.rs

@@ -43,12 +43,12 @@ pub(crate) fn cmd_checkout(
     args: &CheckoutArgs,
 ) -> Result<(), CommandError> {
     writeln!(
-        ui.warning(),
-        "warning: `jj checkout` is deprecated; use `jj new` instead, which is equivalent"
+        ui.warning_with_heading("warning: "),
+        "`jj checkout` is deprecated; use `jj new` instead, which is equivalent"
     )?;
     writeln!(
-        ui.warning(),
-        "warning: `jj checkout` will be removed in a future version, and this will be a hard error"
+        ui.warning_with_heading("warning: "),
+        "`jj checkout` will be removed in a future version, and this will be a hard error"
     )?;
     let mut workspace_command = command.workspace_helper(ui)?;
     let target = workspace_command.resolve_single_rev(&args.revision)?;

cli/src/commands/commit.rs

@@ -78,7 +78,7 @@ new working-copy commit.
     let middle_tree = tx.repo().store().get_root_tree(&tree_id)?;
     if !args.paths.is_empty() && middle_tree.id() == base_tree.id() {
         writeln!(
-            ui.warning(),
+            ui.warning_no_heading(),
             "The given paths do not match any file: {}",
             args.paths.join(" ")
         )?;

cli/src/commands/config.rs

@@ -257,9 +257,9 @@ pub(crate) fn cmd_config_list(
     if !wrote_values {
         // Note to stderr explaining why output is empty.
         if let Some(name) = &args.name {
-            writeln!(ui.warning(), "No matching config key for {name}")?;
+            writeln!(ui.warning_no_heading(), "No matching config key for {name}")?;
         } else {
-            writeln!(ui.warning(), "No config to list")?;
+            writeln!(ui.warning_no_heading(), "No config to list")?;
         }
     }
     Ok(())

cli/src/commands/git.rs

@@ -703,7 +703,7 @@ fn cmd_git_clone(
         };
         if let Err(err) = clean_up_dirs() {
             writeln!(
-                ui.warning(),
+                ui.warning_no_heading(),
                 "Failed to clean up {}: {}",
                 canonical_wc_path.display(),
                 err
@@ -1058,7 +1058,7 @@ struct RejectedBranchUpdateReason {
 
 impl RejectedBranchUpdateReason {
     fn print(&self, ui: &Ui) -> io::Result<()> {
-        writeln!(ui.warning(), "{}", self.message)?;
+        writeln!(ui.warning_no_heading(), "{}", self.message)?;
         if let Some(hint) = &self.hint {
             writeln!(ui.hint_with_heading("Hint: "), "{hint}")?;
         }
@@ -1197,7 +1197,7 @@ fn find_branches_targeted_by_revisions<'a>(
         revision_commit_ids.extend(current_branches_revset.iter());
         if revision_commit_ids.is_empty() {
             writeln!(
-                ui.warning(),
+                ui.warning_no_heading(),
                 "No branches found in the default push revset: \
                  remote_branches(remote={remote_name})..@"
             )?;
@@ -1212,7 +1212,7 @@ fn find_branches_targeted_by_revisions<'a>(
         if commit_ids.peek().is_none() {
             let rev_str: &str = rev_str;
             writeln!(
-                ui.warning(),
+                ui.warning_no_heading(),
                 "No branches point to the specified revisions: {rev_str}"
             )?;
         }

cli/src/commands/init.rs

@@ -62,8 +62,8 @@ pub(crate) fn cmd_init(
     if args.git || args.git_repo.is_some() {
         git::git_init(ui, command, &wc_path, colocate, args.git_repo.as_deref())?;
         writeln!(
-            ui.warning(),
-            "warning: `--git` and `--git-repo` are deprecated.
+            ui.warning_with_heading("warning: "),
+            "`--git` and `--git-repo` are deprecated.
 Use `jj git init` instead"
         )?;
     } else {

cli/src/commands/log.rs

@@ -249,18 +249,18 @@ pub(crate) fn cmd_log(
         if only_path == "." && workspace_command.parse_file_path(only_path)?.is_root() {
             // For users of e.g. Mercurial, where `.` indicates the current commit.
             writeln!(
-                ui.warning(),
-                "warning: The argument {only_path:?} is being interpreted as a path, but this is \
-                 often not useful because all non-empty commits touch '.'.  If you meant to show \
-                 the working copy commit, pass -r '@' instead."
+                ui.warning_with_heading("warning: "),
+                "The argument {only_path:?} is being interpreted as a path, but this is often not \
+                 useful because all non-empty commits touch '.'.  If you meant to show the \
+                 working copy commit, pass -r '@' instead."
             )?;
         } else if revset.is_empty()
             && revset::parse(only_path, &workspace_command.revset_parse_context()).is_ok()
         {
             writeln!(
-                ui.warning(),
-                "warning: The argument {only_path:?} is being interpreted as a path. To specify a \
-                 revset, pass -r {only_path:?} instead."
+                ui.warning_with_heading("warning: "),
+                "The argument {only_path:?} is being interpreted as a path. To specify a revset, \
+                 pass -r {only_path:?} instead."
             )?;
         }
     }

cli/src/commands/merge.rs

@@ -26,12 +26,12 @@ pub(crate) fn cmd_merge(
     args: &new::NewArgs,
 ) -> Result<(), CommandError> {
     writeln!(
-        ui.warning(),
-        "warning: `jj merge` is deprecated; use `jj new` instead, which is equivalent"
+        ui.warning_with_heading("warning: "),
+        "`jj merge` is deprecated; use `jj new` instead, which is equivalent"
     )?;
     writeln!(
-        ui.warning(),
-        "warning: `jj merge` will be removed in a future version, and this will be a hard error"
+        ui.warning_with_heading("warning: "),
+        "`jj merge` will be removed in a future version, and this will be a hard error"
     )?;
     if args.revisions.len() < 2 {
         return Err(cli_error("Merge requires at least two revisions"));

cli/src/commands/move.rs

@@ -63,12 +63,12 @@ pub(crate) fn cmd_move(
     args: &MoveArgs,
 ) -> Result<(), CommandError> {
     writeln!(
-        ui.warning(),
-        "warning: `jj move` is deprecated; use `jj squash` instead, which is equivalent"
+        ui.warning_with_heading("warning: "),
+        "`jj move` is deprecated; use `jj squash` instead, which is equivalent"
     )?;
     writeln!(
-        ui.warning(),
-        "warning: `jj move` will be removed in a future version, and this will be a hard error"
+        ui.warning_with_heading("warning: "),
+        "`jj move` will be removed in a future version, and this will be a hard error"
     )?;
     let mut workspace_command = command.workspace_helper(ui)?;
     let source = workspace_command.resolve_single_rev(args.from.as_deref().unwrap_or("@"))?;

cli/src/commands/operation.rs

@@ -383,7 +383,7 @@ fn cmd_op_abandon(
         let old_op_id = locked_ws.locked_wc().old_operation_id();
         if old_op_id != current_head_op.id() {
             writeln!(
-                ui.warning(),
+                ui.warning_no_heading(),
                 "The working copy operation {} is not updated because it differs from the repo {}.",
                 short_operation_hash(old_op_id),
                 short_operation_hash(current_head_op.id()),

cli/src/commands/split.rs

@@ -94,7 +94,7 @@ don't make any changes, then the operation will be aborted.
     if selected_tree_id == base_tree.id() {
         // The user selected nothing, so the first commit will be empty.
         writeln!(
-            ui.warning(),
+            ui.warning_no_heading(),
             "The given paths do not match any file: {}",
             args.paths.join(" ")
         )?;

cli/src/commands/squash.rs

@@ -199,9 +199,9 @@ from the source will be moved into the destination.
                 .is_ok()
             {
                 writeln!(
-                    ui.warning(),
-                    "warning: The argument {only_path:?} is being interpreted as a path. To \
-                     specify a revset, pass -r {only_path:?} instead."
+                    ui.warning_with_heading("warning: "),
+                    "The argument {only_path:?} is being interpreted as a path. To specify a \
+                     revset, pass -r {only_path:?} instead."
                 )?;
             }
         }

cli/src/commands/util.rs

@@ -130,9 +130,9 @@ fn cmd_util_completion(
     let mut app = command.app().clone();
     let warn = |shell| {
         writeln!(
-            ui.warning(),
-            "Warning: `jj util completion --{shell}` will be removed in a future version, and \
-             this will be a hard error"
+            ui.warning_with_heading("Warning: "),
+            "`jj util completion --{shell}` will be removed in a future version, and this will be \
+             a hard error"
         )?;
         writeln!(
             ui.hint_with_heading("Hint: "),

cli/src/config/colors.toml

@@ -2,6 +2,7 @@
 "error" = "red"
 "warning" = "yellow"
 "hint" = "cyan"
+"warning heading" = { bold = true }
 "hint heading" = { bold = true }
 
 "conflict_description" = "yellow"

cli/src/git_util.rs

@@ -392,7 +392,7 @@ pub fn print_failed_git_export(
     failed_branches: &[FailedRefExport],
 ) -> Result<(), std::io::Error> {
     if !failed_branches.is_empty() {
-        writeln!(ui.warning(), "Failed to export some branches:")?;
+        writeln!(ui.warning_no_heading(), "Failed to export some branches:")?;
         let mut formatter = ui.stderr_formatter();
         for FailedRefExport { name, reason } in failed_branches {
             write!(formatter, "  ")?;

cli/src/merge_tools/external.rs

@@ -324,7 +324,12 @@ pub fn generate_diff(
     let exit_status = child.wait().map_err(ExternalToolError::Io)?;
     tracing::info!(?cmd, ?exit_status, "The external diff generator exited:");
     if !exit_status.success() {
-        writeln!(ui.warning(), "{}", format_tool_aborted(&exit_status)).ok();
+        writeln!(
+            ui.warning_no_heading(),
+            "{}",
+            format_tool_aborted(&exit_status)
+        )
+        .ok();
     }
     copy_result.map_err(ExternalToolError::Io)?;
     Ok(())

cli/src/revset_util.rs

@@ -62,7 +62,10 @@ pub fn load_revset_aliases(
                 .map_err(|e| e.to_string())
                 .and_then(|v| aliases_map.insert(&decl, v).map_err(|e| e.to_string()));
             if let Err(s) = r {
-                writeln!(ui.warning(), r#"Failed to load "{TABLE_KEY}.{decl}": {s}"#)?;
+                writeln!(
+                    ui.warning_no_heading(),
+                    r#"Failed to load "{TABLE_KEY}.{decl}": {s}"#
+                )?;
             }
         }
     }

cli/src/ui.rs

@@ -292,7 +292,7 @@ impl Ui {
                     Err(e) => {
                         // The pager executable couldn't be found or couldn't be run
                         writeln!(
-                            self.warning(),
+                            self.warning_no_heading(),
                             "Failed to spawn pager '{name}': {e}. Consider using the `:builtin` \
                              pager.",
                             name = self.pager_cmd.split_name(),
@@ -386,10 +386,19 @@ impl Ui {
         HeadingLabeledWriter::new(self.stderr_formatter(), "hint", heading)
     }
 
-    pub fn warning(&self) -> LabeledWriter<Box<dyn Formatter + '_>, &'static str> {
+    /// Writer to print warning without the "Warning: " heading.
+    pub fn warning_no_heading(&self) -> LabeledWriter<Box<dyn Formatter + '_>, &'static str> {
         LabeledWriter::new(self.stderr_formatter(), "warning")
     }
 
+    /// Writer to print warning with the given heading.
+    pub fn warning_with_heading<H: fmt::Display>(
+        &self,
+        heading: H,
+    ) -> HeadingLabeledWriter<Box<dyn Formatter + '_>, &'static str, H> {
+        HeadingLabeledWriter::new(self.stderr_formatter(), "warning", heading)
+    }
+
     pub fn error(&self) -> LabeledWriter<Box<dyn Formatter + '_>, &'static str> {
         LabeledWriter::new(self.stderr_formatter(), "error")
     }
@@ -474,7 +483,7 @@ impl Ui {
                 return Ok(choice);
             }
 
-            writeln!(self.warning(), "unrecognized response")?;
+            writeln!(self.warning_no_heading(), "unrecognized response")?;
         }
     }
 

cli/tests/test_global_opts.rs

@@ -388,6 +388,8 @@ fn test_color_config() {
 #[test]
 fn test_color_ui_messages() {
     let test_env = TestEnvironment::default();
+    test_env.jj_cmd_ok(test_env.env_root(), &["git", "init", "repo"]);
+    let repo_path = test_env.env_root().join("repo");
     test_env.add_config("ui.color = 'always'");
 
     // hint and error
@@ -397,6 +399,12 @@ fn test_color_ui_messages() {
     Run `jj config set --user ui.default-command log` to disable this message.
     Error: There is no jj repo in "."
     "###);
+
+    // warning
+    let (_stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["log", "@"]);
+    insta::assert_snapshot!(stderr, @r###"
+    warning: The argument "@" is being interpreted as a path. To specify a revset, pass -r "@" instead.
+    "###);
 }
 
 #[test]