Use let-else instead of match for weak reference upgrades

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1375>

net/aws/src/s3hlssink/imp.rs

@@ -642,9 +642,8 @@ impl ObjectImpl for S3HlsSink {
         self.hlssink.connect("get-playlist-stream", false, {
             let self_weak = self.downgrade();
             move |args| -> Option<glib::Value> {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return None;
-                    None => return None,
                 };
 
                 let s3client = self_.s3client_from_settings();
@@ -677,9 +676,8 @@ impl ObjectImpl for S3HlsSink {
         self.hlssink.connect("get-fragment-stream", false, {
             let self_weak = self.downgrade();
             move |args| -> Option<glib::Value> {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return None;
-                    None => return None,
                 };
 
                 let s3client = self_.s3client_from_settings();
@@ -712,9 +710,8 @@ impl ObjectImpl for S3HlsSink {
         self.hlssink.connect("delete-fragment", false, {
             let self_weak = self.downgrade();
             move |args| -> Option<glib::Value> {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return None;
-                    None => return None,
                 };
 
                 let s3_client = self_.s3client_from_settings();

net/hlssink3/examples/cmaf_live.rs

@@ -269,9 +269,8 @@ fn main() -> Result<(), Error> {
 
         match msg.view() {
             MessageView::StateChanged(state_changed) => {
-                let pipeline = match pipeline_weak.upgrade() {
+                let Some(pipeline) = pipeline_weak.upgrade() else {
-                    Some(pipeline) => pipeline,
+                    break;
-                    None => break,
                 };
 
                 let mut need_write = write_playlist.lock().unwrap();

net/hlssink3/src/imp.rs

@@ -782,9 +782,8 @@ impl ObjectImpl for HlsSink3 {
             .connect("format-location-full", false, {
                 let imp_weak = self.downgrade();
                 move |args| {
-                    let imp = match imp_weak.upgrade() {
+                    let Some(imp) = imp_weak.upgrade() else {
-                        Some(imp) => imp,
+                        return Some(None::<String>.to_value());
-                        None => return Some(None::<String>.to_value()),
                     };
                     let fragment_id = args[1].get::<u32>().unwrap();
                     gst::info!(CAT, imp: imp, "Got fragment-id: {}", fragment_id);
@@ -1322,9 +1321,8 @@ impl ObjectImpl for HlsCmafSink {
         settings.appsink.set_callbacks(
             gst_app::AppSinkCallbacks::builder()
                 .new_sample(move |sink| {
-                    let imp = match self_weak.upgrade() {
+                    let Some(imp) = self_weak.upgrade() else {
-                        Some(imp) => imp,
+                        return Err(gst::FlowError::Eos);
-                        _ => return Err(gst::FlowError::Eos),
                     };
 
                     let sample = sink.pull_sample().map_err(|_| gst::FlowError::Eos)?;

net/ndi/src/device_provider/imp.rs

@@ -87,9 +87,8 @@ impl DeviceProviderImpl for DeviceProvider {
         let mut first = true;
         *thread_guard = Some(thread::spawn(move || {
             {
-                let imp = match imp_weak.upgrade() {
+                let Some(imp) = imp_weak.upgrade() else {
-                    None => return,
+                    return;
-                    Some(imp) => imp,
                 };
 
                 let mut find_guard = imp.find.lock().unwrap();
@@ -109,9 +108,8 @@ impl DeviceProviderImpl for DeviceProvider {
             }
 
             loop {
-                let imp = match imp_weak.upgrade() {
+                let Some(imp) = imp_weak.upgrade() else {
-                    None => return,
+                    return;
-                    Some(imp) => imp,
                 };
 
                 if !imp.is_running.load(atomic::Ordering::SeqCst) {

net/ndi/src/ndisrc/receiver.rs

@@ -761,14 +761,12 @@ impl Receiver {
 
         // Capture until error or shutdown
         loop {
-            let receiver = match receiver.upgrade().map(Receiver) {
+            let Some(receiver) = receiver.upgrade().map(Receiver) else {
-                None => break,
+                break;
-                Some(receiver) => receiver,
             };
 
-            let element = match receiver.0.element.upgrade() {
+            let Some(element) = receiver.0.element.upgrade() else {
-                None => return,
+                break;
-                Some(element) => element,
             };
 
             let flushing = {

net/webrtc/src/whip_signaller/imp.rs

@@ -431,9 +431,8 @@ impl SignallableImpl for Signaller {
                             webrtcbin: &gst::Element| {
                 let obj_weak = signaller.downgrade();
                 webrtcbin.connect_notify(Some("ice-gathering-state"), move |webrtcbin, _pspec| {
-                    let obj = match obj_weak.upgrade() {
+                    let Some(obj) = obj_weak.upgrade() else {
-                        Some(obj) => obj,
+                        return;
-                        None => return,
                     };
 
                     let state =

net/webrtchttp/src/whepsrc/imp.rs

@@ -426,9 +426,8 @@ impl WhepSrc {
         let self_weak = self.downgrade();
         self.webrtcbin
             .connect_notify(Some("ice-gathering-state"), move |webrtcbin, _pspec| {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return;
-                    None => return,
                 };
 
                 let state = webrtcbin.property::<WebRTCICEGatheringState>("ice-gathering-state");
@@ -458,9 +457,8 @@ impl WhepSrc {
         let self_weak = self.downgrade();
         self.webrtcbin
             .connect_notify(Some("ice-connection-state"), move |webrtcbin, _pspec| {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return;
-                    None => return,
                 };
 
                 let state = webrtcbin.property::<WebRTCICEConnectionState>("ice-connection-state");
@@ -489,9 +487,8 @@ impl WhepSrc {
         let self_weak = self.downgrade();
         self.webrtcbin
             .connect_notify(Some("connection-state"), move |webrtcbin, _pspec| {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return;
-                    None => return,
                 };
 
                 let state = webrtcbin.property::<WebRTCPeerConnectionState>("connection-state");
@@ -520,9 +517,8 @@ impl WhepSrc {
 
         let self_weak = self.downgrade();
         self.webrtcbin.connect_pad_added(move |_, pad| {
-            let self_ = match self_weak.upgrade() {
+            let Some(self_) = self_weak.upgrade() else {
-                Some(self_) => self_,
+                return;
-                None => return,
             };
 
             gst::debug!(
@@ -547,9 +543,8 @@ impl WhepSrc {
         let self_weak = self.downgrade();
         self.webrtcbin.connect("on-negotiation-needed", false, {
             move |_| {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return None;
-                    None => return None,
                 };
 
                 let settings = self_.settings.lock().unwrap();
@@ -780,9 +775,8 @@ impl WhepSrc {
     fn generate_offer(&self) {
         let self_weak = self.downgrade();
         let promise = gst::Promise::with_change_func(move |reply| {
-            let self_ = match self_weak.upgrade() {
+            let Some(self_) = self_weak.upgrade() else {
-                Some(self_) => self_,
+                return;
-                None => return,
             };
 
             let reply = match reply {

net/webrtchttp/src/whipsink/imp.rs

@@ -357,9 +357,8 @@ impl ObjectImpl for WhipSink {
         let self_weak = self.downgrade();
         self.webrtcbin
             .connect_notify(Some("ice-gathering-state"), move |webrtcbin, _pspec| {
-                let self_ = match self_weak.upgrade() {
+                let Some(self_) = self_weak.upgrade() else {
-                    Some(self_) => self_,
+                    return;
-                    None => return,
                 };
 
                 let state = webrtcbin.property::<WebRTCICEGatheringState>("ice-gathering-state");

utils/fallbackswitch/examples/gtk_fallbackswitch.rs

@@ -105,9 +105,8 @@ fn create_ui(app: &gtk::Application) {
 
     let video_sink_weak = video_sink.downgrade();
     let timeout_id = glib::timeout_add_local(std::time::Duration::from_millis(100), move || {
-        let video_sink = match video_sink_weak.upgrade() {
+        let Some(video_sink) = video_sink_weak.upgrade() else {
-            Some(video_sink) => video_sink,
+            return glib::ControlFlow::Break;
-            None => return glib::ControlFlow::Continue,
         };
 
         let position = video_sink
@@ -121,9 +120,8 @@ fn create_ui(app: &gtk::Application) {
     let video_src_pad_weak = video_src_pad.downgrade();
     let drop_id = RefCell::new(None);
     drop_button.connect_toggled(move |drop_button| {
-        let video_src_pad = match video_src_pad_weak.upgrade() {
+        let Some(video_src_pad) = video_src_pad_weak.upgrade() else {
-            Some(video_src_pad) => video_src_pad,
+            return;
-            None => return,
         };
 
         let drop = drop_button.is_active();
@@ -140,9 +138,8 @@ fn create_ui(app: &gtk::Application) {
 
     let app_weak = app.downgrade();
     window.connect_close_request(move |_| {
-        let app = match app_weak.upgrade() {
+        let Some(app) = app_weak.upgrade() else {
-            Some(app) => app,
+            return glib::Propagation::Stop;
-            None => return glib::Propagation::Stop,
         };
 
         app.quit();
@@ -155,9 +152,8 @@ fn create_ui(app: &gtk::Application) {
         .add_watch_local(move |_, msg| {
             use gst::MessageView;
 
-            let app = match app_weak.upgrade() {
+            let Some(app) = app_weak.upgrade() else {
-                Some(app) => app,
+                return glib::ControlFlow::Break;
-                None => return glib::ControlFlow::Break,
             };
 
             match msg.view() {

utils/fallbackswitch/src/fallbacksrc/imp.rs

@@ -2893,9 +2893,8 @@ impl FallbackSrc {
         self.obj().call_async(move |element| {
             let imp = element.imp();
 
-            let source = match source_weak.upgrade() {
+            let Some(source) = source_weak.upgrade() else {
-                None => return,
+                return;
-                Some(source) => source,
             };
 
             // Remove blocking pad probes if they are still there as otherwise shutting down the
@@ -3081,9 +3080,8 @@ impl FallbackSrc {
             let element_weak = element.downgrade();
             timeout
                 .wait_async(move |_clock, _time, _id| {
-                    let element = match element_weak.upgrade() {
+                    let Some(element) = element_weak.upgrade() else {
-                        None => return,
+                        return;
-                        Some(element) => element,
                     };
 
                     gst::debug!(CAT, obj: element, "Woke up, retrying");
@@ -3305,9 +3303,8 @@ impl FallbackSrc {
         let element_weak = self.obj().downgrade();
         timeout
             .wait_async(move |_clock, _time, _id| {
-                let element = match element_weak.upgrade() {
+                let Some(element) = element_weak.upgrade() else {
-                    None => return,
+                    return;
-                    Some(element) => element,
                 };
 
                 element.call_async(move |element| {

utils/fallbackswitch/src/fallbackswitch/imp.rs

@@ -583,9 +583,8 @@ impl FallbackSwitch {
         let imp_weak = self.downgrade();
         timeout_id
             .wait_async(move |_clock, _time, clock_id| {
-                let imp = match imp_weak.upgrade() {
+                let Some(imp) = imp_weak.upgrade() else {
-                    None => return,
+                    return;
-                    Some(imp) => imp,
                 };
                 imp.on_timeout(clock_id);
             })

utils/togglerecord/examples/gtk_recording.rs

@@ -217,14 +217,12 @@ fn create_ui(app: &gtk::Application) {
     let video_sink_weak = video_sink.downgrade();
     let togglerecord_weak = togglerecord.downgrade();
     let timeout_id = glib::timeout_add_local(std::time::Duration::from_millis(100), move || {
-        let video_sink = match video_sink_weak.upgrade() {
+        let Some(video_sink) = video_sink_weak.upgrade() else {
-            Some(video_sink) => video_sink,
+            return glib::ControlFlow::Break;
-            None => return glib::ControlFlow::Continue,
         };
 
-        let togglerecord = match togglerecord_weak.upgrade() {
+        let Some(togglerecord) = togglerecord_weak.upgrade() else {
-            Some(togglerecord) => togglerecord,
+            return glib::ControlFlow::Break;
-            None => return glib::ControlFlow::Continue,
         };
 
         let position = video_sink
@@ -244,9 +242,8 @@ fn create_ui(app: &gtk::Application) {
 
     let togglerecord_weak = togglerecord.downgrade();
     record_button.connect_clicked(move |button| {
-        let togglerecord = match togglerecord_weak.upgrade() {
+        let Some(togglerecord) = togglerecord_weak.upgrade() else {
-            Some(togglerecord) => togglerecord,
+            return;
-            None => return,
         };
 
         let recording = !togglerecord.property::<bool>("record");
@@ -257,9 +254,8 @@ fn create_ui(app: &gtk::Application) {
 
     let record_button_weak = record_button.downgrade();
     finish_button.connect_clicked(move |button| {
-        let record_button = match record_button_weak.upgrade() {
+        let Some(record_button) = record_button_weak.upgrade() else {
-            Some(record_button) => record_button,
+            return;
-            None => return,
         };
 
         record_button.set_sensitive(false);
@@ -271,9 +267,8 @@ fn create_ui(app: &gtk::Application) {
 
     let app_weak = app.downgrade();
     window.connect_close_request(move |_| {
-        let app = match app_weak.upgrade() {
+        let Some(app) = app_weak.upgrade() else {
-            Some(app) => app,
+            return glib::Propagation::Stop;
-            None => return glib::Propagation::Stop,
         };
 
         app.quit();
@@ -286,9 +281,8 @@ fn create_ui(app: &gtk::Application) {
         .add_watch_local(move |_, msg| {
             use gst::MessageView;
 
-            let app = match app_weak.upgrade() {
+            let Some(app) = app_weak.upgrade() else {
-                Some(app) => app,
+                return glib::ControlFlow::Break;
-                None => return glib::ControlFlow::Break,
             };
 
             match msg.view() {

utils/tracers/src/pipeline_snapshot/imp.rs

@@ -192,9 +192,8 @@ impl PipelineSnapshot {
             for signal in &mut signals {
                 match signal {
                     SIGUSR1 => {
-                        let tracer = match tracer_weak.upgrade() {
+                        let Some(tracer) = tracer_weak.upgrade() else {
-                            Some(tracer) => tracer,
+                            break;
-                            None => break,
                         };
 
                         let pipelines = {

utils/uriplaylistbin/examples/playlist.rs

@@ -37,9 +37,8 @@ fn create_pipeline(uris: Vec<String>, iterations: u32) -> anyhow::Result<gst::Pi
 
     let pipeline_weak = pipeline.downgrade();
     playlist.connect_pad_added(move |_playlist, src_pad| {
-        let pipeline = match pipeline_weak.upgrade() {
+        let Some(pipeline) = pipeline_weak.upgrade() else {
-            None => return,
+            return;
-            Some(pipeline) => pipeline,
         };
         let pad_name = src_pad.name();
 
@@ -66,9 +65,8 @@ fn create_pipeline(uris: Vec<String>, iterations: u32) -> anyhow::Result<gst::Pi
 
     let pipeline_weak = pipeline.downgrade();
     playlist.connect_pad_removed(move |_playlist, pad| {
-        let pipeline = match pipeline_weak.upgrade() {
+        let Some(pipeline) = pipeline_weak.upgrade() else {
-            None => return,
+            return;
-            Some(pipeline) => pipeline,
         };
 
         // remove sink bin that was handling the pad

utils/uriplaylistbin/src/uriplaylistbin/imp.rs

@@ -1078,9 +1078,8 @@ impl UriPlaylistBin {
                 );
 
                 src_pad.add_probe(gst::PadProbeType::BLOCK_DOWNSTREAM, move |pad, _info| {
-                    let imp = match imp_weak.upgrade() {
+                    let Some(imp) = imp_weak.upgrade() else {
-                        Some(imp) => imp,
+                        return gst::PadProbeReturn::Remove;
-                        None => return gst::PadProbeReturn::Remove,
                     };
 
                     if let Some(parent) = pad.parent() {
@@ -1294,9 +1293,8 @@ impl UriPlaylistBin {
                             return gst::PadProbeReturn::Pass;
                         }
 
-                        let element = match element_weak.upgrade() {
+                        let Some(element) = element_weak.upgrade() else {
-                            Some(element) => element,
+                            return gst::PadProbeReturn::Remove;
-                            None => return gst::PadProbeReturn::Remove,
                         };
                         let imp = element.imp();
 
@@ -1396,14 +1394,12 @@ impl UriPlaylistBin {
             let item_weak = item.downgrade();
 
             sink_pad.add_probe(gst::PadProbeType::BLOCK_DOWNSTREAM, move |pad, info| {
-                let element = match element_weak.upgrade() {
+                let Some(element) = element_weak.upgrade() else {
-                    Some(element) => element,
+                    return gst::PadProbeReturn::Remove;
-                    None => return gst::PadProbeReturn::Remove,
                 };
                 let parent = pad.parent().unwrap();
-                let item = match Item::upgrade(&item_weak) {
+                let Some(item) = Item::upgrade(&item_weak) else {
-                    Some(item) => item,
+                    return gst::PadProbeReturn::Remove;
-                    None => return gst::PadProbeReturn::Remove,
                 };
 
                 if !item.is_streaming() {

utils/uriplaylistbin/tests/uriplaylistbin.rs

@@ -110,9 +110,8 @@ fn test(
             return;
         }
 
-        let pipeline = match pipeline_weak.upgrade() {
+        let Some(pipeline) = pipeline_weak.upgrade() else {
-            Some(pipeline) => pipeline,
+            return;
-            None => return,
         };
 
         let sink = gst::ElementFactory::make("fakesink").build().unwrap();

video/closedcaption/src/transcriberbin/imp.rs

@@ -290,9 +290,8 @@ impl TranscriberBin {
         let comp_sinkpad = &state.cccombiner.static_pad("sink").unwrap();
         // Drop caption meta from video buffer if user preference is transcription
         comp_sinkpad.add_probe(gst::PadProbeType::BUFFER, move |_, probe_info| {
-            let imp = match imp_weak.upgrade() {
+            let Some(imp) = imp_weak.upgrade() else {
-                None => return gst::PadProbeReturn::Remove,
+                return gst::PadProbeReturn::Remove;
-                Some(imp) => imp,
             };
 
             let settings = imp.settings.lock().unwrap();
@@ -431,9 +430,8 @@ impl TranscriberBin {
                         | gst::PadProbeType::BUFFER
                         | gst::PadProbeType::EVENT_DOWNSTREAM,
                     move |_pad, _info| {
-                        let imp = match imp_weak.upgrade() {
+                        let Some(imp) = imp_weak.upgrade() else {
-                            None => return gst::PadProbeReturn::Pass,
+                            return gst::PadProbeReturn::Remove;
-                            Some(imp) => imp,
                         };
 
                         imp.disable_transcription_bin();
@@ -645,9 +643,8 @@ impl TranscriberBin {
                     | gst::PadProbeType::BUFFER
                     | gst::PadProbeType::EVENT_DOWNSTREAM,
                 move |_pad, _info| {
-                    let imp = match imp_weak.upgrade() {
+                    let Some(imp) = imp_weak.upgrade() else {
-                        None => return gst::PadProbeReturn::Remove,
+                        return gst::PadProbeReturn::Remove;
-                        Some(imp) => imp,
                     };
 
                     if imp.reconfigure_transcription_bin(lang_code_only).is_err() {

video/gtk4/examples/gtksink.rs

@@ -75,9 +75,8 @@ fn create_ui(app: &gtk::Application) {
 
     let pipeline_weak = pipeline.downgrade();
     let timeout_id = glib::timeout_add_local(std::time::Duration::from_millis(500), move || {
-        let pipeline = match pipeline_weak.upgrade() {
+        let Some(pipeline) = pipeline_weak.upgrade() else {
-            Some(pipeline) => pipeline,
+            return glib::ControlFlow::Break;
-            None => return glib::ControlFlow::Continue,
         };
 
         let position = pipeline.query_position::<gst::ClockTime>();
@@ -96,9 +95,8 @@ fn create_ui(app: &gtk::Application) {
         .add_watch_local(move |_, msg| {
             use gst::MessageView;
 
-            let app = match app_weak.upgrade() {
+            let Some(app) = app_weak.upgrade() else {
-                Some(app) => app,
+                return glib::ControlFlow::Break;
-                None => return glib::ControlFlow::Break,
             };
 
             match msg.view() {