cli: add a global --quiet flag, which silences status messages

Note that `jj resolve` already had its own `--quiet` flag. The output
with `--quiet` for that command got a lot quieter with the global
`--quiet` also taking effect. That seems reasonable to me.

CHANGELOG.md

@@ -58,6 +58,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 * `--all` is now named `--all-remotes` for `jj branch list`
 
+* There is a new global `--quiet` flag to silence commands' non-primary output.
+
 ### Fixed bugs
 
 ## [0.15.1] - 2024-03-06

cli/src/cli_util.rs

@@ -2137,6 +2137,16 @@ pub struct EarlyArgs {
     /// When to colorize output (always, never, auto)
     #[arg(long, value_name = "WHEN", global = true)]
     pub color: Option<ColorChoice>,
+    /// Silence non-primary command output
+    ///
+    /// For example, `jj files` will still list files, but it won't tell you if
+    /// the working copy was snapshotted or if descendants were rebased.
+    ///
+    /// Warnings and errors will still be printed.
+    #[arg(long, global = true, action = ArgAction::SetTrue)]
+    // Parsing with ignore_errors will crash if this is bool, so use
+    // Option<bool>.
+    pub quiet: Option<bool>,
     /// Disable the pager
     #[arg(long, value_name = "WHEN", global = true, action = ArgAction::SetTrue)]
     // Parsing with ignore_errors will crash if this is bool, so use
@@ -2306,6 +2316,9 @@ fn handle_early_args(
     if let Some(choice) = args.color {
         args.config_toml.push(format!(r#"ui.color="{choice}""#));
     }
+    if args.quiet.unwrap_or_default() {
+        args.config_toml.push(r#"ui.quiet=true"#.to_string());
+    }
     if args.no_pager.unwrap_or_default() {
         args.config_toml.push(r#"ui.paginate="never""#.to_owned());
     }

cli/src/ui.rs

@@ -163,6 +163,7 @@ impl Write for UiStderr<'_> {
 
 pub struct Ui {
     color: bool,
+    quiet: bool,
     pager_cmd: CommandNameAndArgs,
     paginate: PaginationChoice,
     progress_indicator: bool,
@@ -222,6 +223,10 @@ fn use_color(choice: ColorChoice) -> bool {
     }
 }
 
+fn be_quiet(config: &config::Config) -> bool {
+    config.get_bool("ui.quiet").unwrap_or_default()
+}
+
 #[derive(Clone, Copy, Debug, Default, Eq, PartialEq, serde::Deserialize)]
 #[serde(rename_all(deserialize = "kebab-case"))]
 pub enum PaginationChoice {
@@ -245,6 +250,7 @@ fn pager_setting(config: &config::Config) -> Result<CommandNameAndArgs, CommandE
 impl Ui {
     pub fn with_config(config: &config::Config) -> Result<Ui, CommandError> {
         let color = use_color(color_setting(config));
+        let quiet = be_quiet(config);
         // Sanitize ANSI escape codes if we're printing to a terminal. Doesn't affect
         // ANSI escape codes that originate from the formatter itself.
         let sanitize = io::stdout().is_terminal();
@@ -252,6 +258,7 @@ impl Ui {
         let progress_indicator = progress_indicator_setting(config);
         Ok(Ui {
             color,
+            quiet,
             formatter_factory,
             pager_cmd: pager_setting(config)?,
             paginate: pagination_setting(config)?,
@@ -262,6 +269,7 @@ impl Ui {
 
     pub fn reset(&mut self, config: &config::Config) -> Result<(), CommandError> {
         self.color = use_color(color_setting(config));
+        self.quiet = be_quiet(config);
         self.paginate = pagination_setting(config)?;
         self.pager_cmd = pager_setting(config)?;
         self.progress_indicator = progress_indicator_setting(config);
@@ -375,14 +383,17 @@ impl Ui {
 
     /// Writer to print an update that's not part of the command's main output.
     pub fn status(&self) -> Box<dyn Write + '_> {
-        Box::new(self.stderr())
+        if self.quiet {
+            Box::new(std::io::sink())
+        } else {
+            Box::new(self.stderr())
+        }
     }
 
     /// A formatter to print an update that's not part of the command's main
     /// output. Returns `None` if `--quiet` was requested.
-    // TODO: Actually support `--quiet`
     pub fn status_formatter(&self) -> Option<Box<dyn Formatter + '_>> {
-        Some(self.stderr_formatter())
+        (!self.quiet).then(|| self.stderr_formatter())
     }
 
     /// Writer to print hint with the default "Hint: " heading.
@@ -394,7 +405,7 @@ impl Ui {
 
     /// Writer to print hint without the "Hint: " heading.
     pub fn hint_no_heading(&self) -> Option<LabeledWriter<Box<dyn Formatter + '_>, &'static str>> {
-        Some(LabeledWriter::new(self.stderr_formatter(), "hint"))
+        (!self.quiet).then(|| LabeledWriter::new(self.stderr_formatter(), "hint"))
     }
 
     /// Writer to print hint with the given heading.
@@ -402,11 +413,7 @@ impl Ui {
         &self,
         heading: H,
     ) -> Option<HeadingLabeledWriter<Box<dyn Formatter + '_>, &'static str, H>> {
-        Some(HeadingLabeledWriter::new(
-            self.stderr_formatter(),
-            "hint",
-            heading,
-        ))
+        (!self.quiet).then(|| HeadingLabeledWriter::new(self.stderr_formatter(), "hint", heading))
     }
 
     /// Writer to print warning with the default "Warning: " heading.

cli/tests/cli-reference@.md.snap

@@ -159,6 +159,10 @@ To get started, see the tutorial at https://github.com/martinvonz/jj/blob/main/d
   Possible values: `true`, `false`
 
 * `--color <WHEN>` — When to colorize output (always, never, auto)
+* `--quiet` — Silence non-primary command output
+
+  Possible values: `true`, `false`
+
 * `--no-pager` — Disable the pager
 
   Possible values: `true`, `false`

cli/tests/test_global_opts.rs

@@ -441,6 +441,19 @@ fn test_color_ui_messages() {
     "###);
 }
 
+#[test]
+fn test_quiet() {
+    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");
+
+    // Can skip message about new working copy with `--quiet`
+    std::fs::write(repo_path.join("file1"), "contents").unwrap();
+    let (_stdout, stderr) =
+        test_env.jj_cmd_ok(&repo_path, &["--quiet", "describe", "-m=new description"]);
+    insta::assert_snapshot!(stderr, @"");
+}
+
 #[test]
 fn test_early_args() {
     // Test that help output parses early args
@@ -535,6 +548,7 @@ fn test_help() {
           --at-operation <AT_OPERATION>  Operation to load the repo at [default: @] [aliases: at-op]
           --debug                        Enable debug logging
           --color <WHEN>                 When to colorize output (always, never, auto)
+          --quiet                        Silence non-primary command output
           --no-pager                     Disable the pager
           --config-toml <TOML>           Additional configuration options (can be repeated)
     "###);

cli/tests/test_resolve_command.rs

@@ -728,20 +728,7 @@ fn test_multiple_conflicts() {
     std::fs::write(&editor_script, "expect\n\0write\nresolution another_file\n").unwrap();
     let (stdout, stderr) = test_env.jj_cmd_ok(&repo_path, &["resolve", "--quiet", "another_file"]);
     insta::assert_snapshot!(stdout, @"");
-    insta::assert_snapshot!(stderr, @r###"
-    Resolving conflicts in: another_file
-    New conflicts appeared in these commits:
-      vruxwmqv 3c438f88 conflict | (conflict) conflict
-    To resolve the conflicts, start by updating to it:
-      jj new vruxwmqvtpmx
-    Then use `jj resolve`, or edit the conflict markers in the file directly.
-    Once the conflicts are resolved, you may want inspect the result with `jj diff`.
-    Then run `jj squash` to move the resolution into the conflicted commit.
-    Working copy now at: vruxwmqv 3c438f88 conflict | (conflict) conflict
-    Parent commit      : zsuskuln de7553ef a | a
-    Parent commit      : royxmykx f68bc2f0 b | b
-    Added 0 files, modified 1 files, removed 0 files
-    "###);
+    insta::assert_snapshot!(stderr, @"");
 
     // For the rest of the test, we call `jj resolve` several times in a row to
     // resolve each conflict in the order it chooses.