Fix all lints that are new with Rust 1.54

They are all of the following type:
https://rust-lang.github.io/rust-clippy/master/index.html#needless_borrow

src/assets.rs

@@ -408,7 +408,7 @@ impl SerializedSyntaxSet {
     fn deserialize(&self) -> Result<SyntaxSet> {
         match self {
             SerializedSyntaxSet::FromBinary(data) => Ok(from_binary(data)),
-            SerializedSyntaxSet::FromFile(ref path) => asset_from_cache(&path, "syntax set"),
+            SerializedSyntaxSet::FromFile(ref path) => asset_from_cache(path, "syntax set"),
         }
     }
 }

src/bin/bat/app.rs

@@ -301,7 +301,7 @@ impl App {
                     .map(|style_str| {
                         style_str
                             .split(',')
-                            .map(|x| StyleComponent::from_str(&x))
+                            .map(|x| StyleComponent::from_str(x))
                             .collect::<Result<Vec<StyleComponent>>>()
                     })
                     .transpose()?;

src/bin/bat/assets.rs

@@ -25,7 +25,7 @@ pub fn clear_assets() {
 
 pub fn assets_from_cache_or_binary(use_custom_assets: bool) -> Result<HighlightingAssets> {
     let cache_dir = PROJECT_DIRS.cache_dir();
-    if let Some(metadata) = AssetsMetadata::load_from_folder(&cache_dir)? {
+    if let Some(metadata) = AssetsMetadata::load_from_folder(cache_dir)? {
         if !metadata.is_compatible_with(crate_version!()) {
             return Err(format!(
                 "The binary caches for the user-customized syntaxes and themes \
@@ -42,7 +42,7 @@ pub fn assets_from_cache_or_binary(use_custom_assets: bool) -> Result<Highlighti
     }
 
     let custom_assets = if use_custom_assets {
-        HighlightingAssets::from_cache(&cache_dir).ok()
+        HighlightingAssets::from_cache(cache_dir).ok()
     } else {
         None
     };

src/bin/bat/main.rs

@@ -226,7 +226,7 @@ pub fn list_themes(cfg: &Config) -> Result<()> {
 
 fn run_controller(inputs: Vec<Input>, config: &Config) -> Result<bool> {
     let assets = assets_from_cache_or_binary(config.use_custom_assets)?;
-    let controller = Controller::new(&config, &assets);
+    let controller = Controller::new(config, &assets);
     controller.run(inputs)
 }
 

src/controller.rs

@@ -45,7 +45,7 @@ impl<'b> Controller<'b> {
             // Do not launch the pager if NONE of the input files exist
             let mut paging_mode = self.config.paging_mode;
             if self.config.paging_mode != PagingMode::Never {
-                let call_pager = inputs.iter().any(|ref input| {
+                let call_pager = inputs.iter().any(|input| {
                     if let InputKind::OrdinaryFile(ref path) = input.kind {
                         Path::new(path).exists()
                     } else {
@@ -124,11 +124,11 @@ impl<'b> Controller<'b> {
                     };
 
                     let mut printer: Box<dyn Printer> = if self.config.loop_through {
-                        Box::new(SimplePrinter::new(&self.config))
+                        Box::new(SimplePrinter::new(self.config))
                     } else {
                         Box::new(InteractivePrinter::new(
-                            &self.config,
-                            &self.assets,
+                            self.config,
+                            self.assets,
                             &mut opened_input,
                             #[cfg(feature = "git")]
                             &line_changes,

src/input.rs

@@ -51,7 +51,7 @@ impl InputDescription {
 
     pub fn title(&self) -> &String {
         match self.title.as_ref() {
-            Some(ref title) => title,
+            Some(title) => title,
             None => &self.name,
         }
     }

src/printer.rs

@@ -372,19 +372,19 @@ impl<'a> Printer for InteractivePrinter<'a> {
         line_buffer: &[u8],
     ) -> Result<()> {
         let line = if self.config.show_nonprintable {
-            replace_nonprintable(&line_buffer, self.config.tab_width)
+            replace_nonprintable(line_buffer, self.config.tab_width)
         } else {
             match self.content_type {
                 Some(ContentType::BINARY) | None => {
                     return Ok(());
                 }
                 Some(ContentType::UTF_16LE) => UTF_16LE
-                    .decode(&line_buffer, DecoderTrap::Replace)
+                    .decode(line_buffer, DecoderTrap::Replace)
                     .map_err(|_| "Invalid UTF-16LE")?,
                 Some(ContentType::UTF_16BE) => UTF_16BE
-                    .decode(&line_buffer, DecoderTrap::Replace)
+                    .decode(line_buffer, DecoderTrap::Replace)
                     .map_err(|_| "Invalid UTF-16BE")?,
-                _ => String::from_utf8_lossy(&line_buffer).to_string(),
+                _ => String::from_utf8_lossy(line_buffer).to_string(),
             }
         };
 
@@ -420,7 +420,7 @@ impl<'a> Printer for InteractivePrinter<'a> {
             let decorations = self
                 .decorations
                 .iter()
-                .map(|ref d| d.generate(line_number, false, self))
+                .map(|d| d.generate(line_number, false, self))
                 .collect::<Vec<_>>();
 
             for deco in decorations {
@@ -531,7 +531,7 @@ impl<'a> Printer for InteractivePrinter<'a> {
                                                 "{} ",
                                                 self.decorations
                                                     .iter()
-                                                    .map(|ref d| d
+                                                    .map(|d| d
                                                         .generate(line_number, true, self)
                                                         .text)
                                                     .collect::<Vec<String>>()