Slightly improve code making use of element factories retrieved from an element

We can use `is_some_and(...)` instead of `map_or(false, ...)`.

Also in a few places the factory was retrieved multiple times, one time
with unwrapping and another time with handling the `None` case
correctly. Instead of unwrapping, move code to handle the `None` case.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-rs/-/merge_requests/1630>

net/aws/src/s3hlssink/imp.rs

@@ -740,7 +740,11 @@ impl ObjectImpl for S3HlsSink {
 
                 // The signature on delete-fragment signal is different for
                 // hlssink2 and hlssink3.
-                if self_.hlssink.factory().unwrap().name().contains("hlssink3") {
+                if self_
+                    .hlssink
+                    .factory()
+                    .is_some_and(|factory| factory.name() == "hlssink3")
+                {
                     if res.is_ok() {
                         Some(true.to_value())
                     } else {

net/webrtc/examples/webrtcsink-high-quality-tune.rs

@@ -40,12 +40,13 @@ fn main() -> Result<(), Error> {
         pipeline.connect("deep-element-added", false, |values| {
             let element = values[2].get::<gst::Element>().unwrap();
 
-            if let Some(factory) = element.factory() {
+            if element
-                if factory.name().as_str() == "videoscale" {
+                .factory()
+                .is_some_and(|factory| factory.name() == "videoscale")
+            {
                 println!("Tuning videoscale");
                 element.set_property_from_str("method", "lanczos");
             }
-            }
 
             None
         });
@@ -61,9 +62,9 @@ fn main() -> Result<(), Error> {
     webrtcsink.connect("encoder-setup", true, |values| {
         let encoder = values[3].get::<gst::Element>().unwrap();
 
-        println!("Encoder: {}", encoder.factory().unwrap().name());
-
         if let Some(factory) = encoder.factory() {
+            println!("Encoder: {}", factory.name());
+
             match factory.name().as_str() {
                 "x264enc" => {
                     println!("Applying extra configuration to x264enc");

net/webrtc/examples/webrtcsink-stats-server.rs

@@ -137,9 +137,8 @@ async fn run(args: Args) -> Result<(), Error> {
     ws.connect("encoder-setup", false, |values| {
         let encoder = values[3].get::<gst::Element>().unwrap();
 
-        info!("Encoder: {}", encoder.factory().unwrap().name());
-
         let configured = if let Some(factory) = encoder.factory() {
+            info!("Encoder: {}", factory.name());
             matches!(factory.name().as_str(), "does-not-exist")
         } else {
             false

net/webrtc/src/webrtcsink/imp.rs

@@ -559,7 +559,7 @@ fn make_converter_for_video_caps(caps: &gst::Caps, codec: &Codec) -> Result<gst:
                 // corresponding converter
                 || codec
                 .encoder_factory()
-                .map_or(false, |factory| factory.name().starts_with("nvv4l2"))
+                .is_some_and(|factory| factory.name().starts_with("nvv4l2"))
             {
                 let queue = make_element("queue", None)?;
                 let nvconvert = if let Ok(nvconvert) = make_element("nvvideoconvert", None) {
@@ -788,7 +788,8 @@ fn configure_encoder(enc: &gst::Element, start_bitrate: u32) {
 fn configure_payloader(pay: &gst::Element) {
     pay.set_property("mtu", 1200_u32);
 
-    match pay.factory().unwrap().name().as_str() {
+    if let Some(factory) = pay.factory() {
+        match factory.name().as_str() {
             "rtpvp8pay" | "rtpvp9pay" => {
                 pay.set_property_from_str("picture-id-mode", "15-bit");
             }
@@ -799,6 +800,7 @@ fn configure_payloader(pay: &gst::Element) {
             _ => (),
         }
     }
+}
 
 fn setup_signal_accumulator(
     _hint: &glib::subclass::SignalInvocationHint,
@@ -950,13 +952,7 @@ impl VideoEncoder {
     ) -> Option<Self> {
         let halved_framerate = video_info.fps().mul(gst::Fraction::new(1, 2));
         Some(Self {
-            factory_name: encoding_elements
+            factory_name: encoding_elements.encoder.as_ref()?.factory()?.name().into(),
-                .encoder
-                .as_ref()?
-                .factory()
-                .unwrap()
-                .name()
-                .into(),
             codec_name: codec_name.to_string(),
             element: encoding_elements.encoder.as_ref()?.clone(),
             filter: encoding_elements.raw_filter.as_ref()?.clone(),
@@ -2634,7 +2630,7 @@ impl BaseWebRTCSink {
                     glib::closure!(@watch element, @strong session_id
                             => move |_webrtcbin: gst::Element, _bin: gst::Bin, e: gst::Element| {
 
-                        if e.factory().map_or(false, |f| f.name() == "rtprtxsend") {
+                        if e.factory().is_some_and(|f| f.name() == "rtprtxsend") {
                             if e.has_property("stuffing-kbps", Some(i32::static_type())) {
                                 element.imp().set_rtptrxsend(element, &session_id, e);
                             } else {