Fix or ignore various clippy warnings

And ignore some common warnings we don't care about in general, while
also making clippy errors fail the build.

.gitlab-ci.yml

@@ -124,7 +124,6 @@ clippy:
   extends: '.tarball_setup'
   image: "rust:slim"
   stage: 'extras'
-  allow_failure: true
   script:
     - rustup component add clippy-preview
     - cargo clippy --version
@@ -141,5 +140,9 @@ clippy:
           FEATURES=v1_16
         fi
 
-        cargo clippy --color=always --manifest-path $crate/Cargo.toml --features=$FEATURES
+        cargo clippy --color=always --manifest-path $crate/Cargo.toml --features=$FEATURES -- -A clippy::redundant_pattern_matching -A clippy::single_match -A clippy::cast_lossless
       done
+    # And also run over all the examples/tutorials
+    - |
+      cargo clippy --color=always --manifest-path examples/Cargo.toml --bins --examples --all-features -- -A clippy::redundant_pattern_matching -A clippy::single_match -A clippy::cast_lossless
+      cargo clippy --color=always --manifest-path tutorials/Cargo.toml --bins --examples --all-features -- -A clippy::redundant_pattern_matching -A clippy::single_match -A clippy::cast_lossless

examples/src/bin/glupload.rs

@@ -408,6 +408,7 @@ impl App {
                         gst_gl::GLPlatform::GLX,
                     )
                 }
+                #[allow(unreachable_patterns)]
                 handler => panic!("Unsupported platform: {:?}.", handler),
             };
 

gstreamer-rtsp-server/src/lib.rs

@@ -46,6 +46,7 @@ pub use glib::{Cast, Continue, Error, IsA, StaticType, ToValue, Type, TypedValue
 #[allow(clippy::too_many_arguments)]
 #[allow(clippy::match_same_arms)]
 #[allow(clippy::type_complexity)]
+#[allow(clippy::let_and_return)]
 mod auto;
 pub use auto::*;
 

gstreamer-video/src/video_format_info.rs

@@ -145,6 +145,7 @@ impl VideoFormatInfo {
         (-((-(i64::from(height))) >> self.h_sub()[component as usize])) as u32
     }
 
+    #[allow(clippy::too_many_arguments)]
     pub fn unpack(
         &self,
         flags: ::VideoPackFlags,
@@ -220,6 +221,7 @@ impl VideoFormatInfo {
         }
     }
 
+    #[allow(clippy::too_many_arguments)]
     pub fn pack(
         &self,
         flags: ::VideoPackFlags,

gstreamer/src/date_time_serde.rs

@@ -130,7 +130,7 @@ impl TryFrom<DateTimeVariants> for Date {
 impl<'de> Deserialize<'de> for Date {
     fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
         DateTimeVariants::deserialize(deserializer)
-            .and_then(|dt_variant| dt_variant.try_into().map_err(|err| D::Error::custom(err)))
+            .and_then(|dt_variant| dt_variant.try_into().map_err(D::Error::custom))
     }
 }
 

gstreamer/src/event.rs

@@ -1410,6 +1410,8 @@ impl<'a> SeekBuilder<'a> {
     }
 
     event_builder_generic_impl!(|s: &Self| {
+        #[allow(clippy::let_and_return)]
+        {
             let ev = gst_sys::gst_event_new_seek(
                 s.rate,
                 s.start.get_format().to_glib(),
@@ -1423,11 +1425,15 @@ impl<'a> SeekBuilder<'a> {
             #[cfg(any(feature = "v1_16", feature = "dox"))]
             {
                 if let Some(trickmode_interval) = s.trickmode_interval {
-                gst_sys::gst_event_set_seek_trickmode_interval(ev, trickmode_interval.to_glib());
+                    gst_sys::gst_event_set_seek_trickmode_interval(
+                        ev,
+                        trickmode_interval.to_glib(),
+                    );
                 }
             }
 
             ev
+        }
     });
 }
 

gstreamer/src/functions.rs

@@ -115,7 +115,12 @@ pub fn calculate_linear_regression(
     unsafe {
         assert_eq!(mem::size_of::<u64>() * 2, mem::size_of::<(u64, u64)>());
         assert_eq!(mem::align_of::<u64>(), mem::align_of::<(u64, u64)>());
-        assert!(temp.as_ref().map(|temp| temp.len()).unwrap_or(xy.len()) >= xy.len());
+        assert!(
+            temp.as_ref()
+                .map(|temp| temp.len())
+                .unwrap_or_else(|| xy.len())
+                >= xy.len()
+        );
 
         let mut m_num = mem::MaybeUninit::uninit();
         let mut m_denom = mem::MaybeUninit::uninit();