refactor: fix some clippy lints

cargo clippy --no-deps -- --warn clippy::nursery --warn clippy::pedantic

src/app/maybe_image.rs

@@ -7,7 +7,7 @@ pub enum MaybeImage {
     Unloaded,
 
     #[allow(dead_code)]
-    /// should be abort_on_drop,
+    /// should be `abort_on_drop`,
     /// so that it will abort, for instance,
     /// when it's set back to `Self::Unloaded`
     Loading(task::Handle),
@@ -15,9 +15,9 @@ pub enum MaybeImage {
     Loaded(widget::image::Handle),
 }
 impl MaybeImage {
-    pub fn handle(&self) -> Option<&widget::image::Handle> {
+    pub const fn handle(&self) -> Option<&widget::image::Handle> {
         match self {
-            Self::Loaded(h) => Some(&h),
+            Self::Loaded(h) => Some(h),
             _ => None,
         }
     }

src/app/mod.rs

@@ -103,15 +103,15 @@ impl State {
                 }
             }
             Message::ImageLoaded(result) => {
-                self.error = result.as_ref().err().map(|e| e.to_string());
+                self.error = result.as_ref().err().map(ToString::to_string);
 
                 if let Ok((path, handle)) = result {
                     let entry = self.images.entry(path).or_default();
 
                     if matches!(entry, MaybeImage::Loaded(_)) {
-                        self.error = Some("tried to load already-loaded image!".into())
+                        self.error = Some("tried to load already-loaded image!".into());
                     } else {
-                        *entry = MaybeImage::Loaded(handle)
+                        *entry = MaybeImage::Loaded(handle);
                     }
                 }
             }
@@ -141,7 +141,7 @@ impl State {
             }
 
             Message::FocusNext => return widget::operation::focus_next(),
-            Message::FocusPrevious => return widget::operation::focus_next(),
+            Message::FocusPrevious => return widget::operation::focus_previous(),
 
             Message::PickPath => {
                 return Task::perform(
@@ -233,16 +233,18 @@ impl State {
                     keyboard::Key::Character("j")
                     | keyboard::Key::Named(
                         keyboard::key::Named::ArrowDown | keyboard::key::Named::PageDown,
-                    ) => Some(Message::ScrollBy(match modifiers.shift() {
-                        false => 100.,
-                        true => 500.,
+                    ) => Some(Message::ScrollBy(if modifiers.shift() {
+                        500.
+                    } else {
+                        100.
                     })),
                     keyboard::Key::Character("k")
                     | keyboard::Key::Named(
                         keyboard::key::Named::ArrowUp | keyboard::key::Named::PageUp,
-                    ) => Some(Message::ScrollBy(match modifiers.shift() {
-                        false => -100.,
-                        true => -500.,
+                    ) => Some(Message::ScrollBy(if modifiers.shift() {
+                        -500.
+                    } else {
+                        -100.
                     })),
 
                     keyboard::Key::Character("=" | "+") => Some(Message::IncreaseColumns),
@@ -275,7 +277,7 @@ impl State {
             .filter_map(|r| {
                 r.inspect_err(|e| eprintln!("{e}"))
                     .ok()
-                    .map(|entry| entry.into_path())
+                    .map(ignore::DirEntry::into_path)
             })
             .filter(|path| path.is_file())
             .map(|path| (path, MaybeImage::Unloaded))