feat: report installation progress to terminal

crates/pixi_progress/src/lib.rs

@@ -1,3 +1,4 @@
+pub mod osc;
 mod placement;
 pub mod style;
 

crates/pixi_progress/src/osc.rs

@@ -0,0 +1,46 @@
+use std::io::{IsTerminal, Write};
+use std::sync::LazyLock;
+
+use parking_lot::Mutex;
+
+/// Cached check for whether stdout is a terminal.
+static IS_TERMINAL: LazyLock<bool> = LazyLock::new(|| std::io::stdout().is_terminal());
+
+/// Last emitted percentage, used to avoid redundant writes.
+static LAST_PCT: Mutex<Option<u8>> = Mutex::new(None);
+
+/// Emit an OSC 9;4 progress sequence to stdout.
+///
+/// Terminal emulators that support OSC 9;4 (Windows Terminal, iTerm2,
+/// WezTerm, ConEmu, etc.) display this as progress in the title bar
+/// or taskbar icon.
+///
+/// Uses ST (ESC \) as the string terminator for broad compatibility.
+pub fn set_progress(position: u64, length: u64) {
+    if !*IS_TERMINAL || length == 0 || crate::global_multi_progress().is_hidden() {
+        return;
+    }
+    let pct = (position * 100 / length).min(100) as u8;
+    let mut last = LAST_PCT.lock();
+    if *last != Some(pct) {
+        *last = Some(pct);
+        let seq = format!("\x1b]9;4;1;{pct}\x1b\\");
+        let mut stdout = std::io::stdout().lock();
+        let _ = stdout.write_all(seq.as_bytes());
+        let _ = stdout.flush();
+    }
+}
+
+/// Clear the OSC 9;4 progress indicator.
+pub fn clear_progress() {
+    if !*IS_TERMINAL || crate::global_multi_progress().is_hidden() {
+        return;
+    }
+    let mut last = LAST_PCT.lock();
+    if last.is_some() {
+        *last = None;
+        let mut stdout = std::io::stdout().lock();
+        let _ = stdout.write_all(b"\x1b]9;4;0;0\x1b\\");
+        let _ = stdout.flush();
+    }
+}

crates/pixi_reporters/src/main_progress_bar.rs

@@ -29,6 +29,9 @@ struct State<T> {
     /// The items that are being tracked by this progress bar.
     tracker: Arc<RwLock<HashMap<usize, TrackedItem<T>>>>,
     next_tracker_id: usize,
+
+    /// Whether to emit OSC 9;4 terminal progress reporting.
+    osc_report: bool,
 }
 
 /// A trait for something that can be tracked by the [`MainProgressBar`].
@@ -72,10 +75,17 @@ impl<T: Tracker> MainProgressBar<T> {
                 title: Some(title),
                 tracker: Arc::new(RwLock::new(HashMap::new())),
                 next_tracker_id: 0,
+                osc_report: false,
             })),
         }
     }
 
+    /// Enable OSC 9;4 terminal progress reporting on this bar.
+    pub fn with_osc_report(self) -> Self {
+        self.inner.write().osc_report = true;
+        self
+    }
+
     /// Called when an item is queued for processing.
     pub fn queued(&self, tracker: T) -> usize {
         let mut state = self.inner.write();
@@ -120,6 +130,9 @@ impl<T: Tracker> State<T> {
 
         // Clear or update the progress bar.
         if is_empty {
+            if self.osc_report {
+                pixi_progress::osc::clear_progress();
+            }
             // We cannot clear the progress bar and restart it later, so replacing it with a
             // new hidden one is currently the only option.
             self.title = Some(self.pb.prefix());
@@ -225,6 +238,10 @@ impl<T: Tracker> State<T> {
             state.set_pos(position);
         });
         self.pb.set_message(wide_msg);
+
+        if self.osc_report {
+            pixi_progress::osc::set_progress(position, length);
+        }
     }
 }
 

crates/pixi_reporters/src/sync_reporter.rs

@@ -256,7 +256,8 @@ impl CombinedInstallReporterInner {
             multi_progress.clone(),
             ProgressBarPlacement::After(preparing_progress_bar.progress_bar()),
             "installing".to_owned(),
-        );
+        )
+        .with_osc_report();
 
         Self {
             next_id: std::sync::atomic::AtomicUsize::new(0),