Fix clippy warnings

src/assets.rs

@@ -57,10 +57,7 @@ impl HighlightingAssets {
             )
         })?;
         let mut syntax_set: SyntaxSet = from_reader(syntax_set_file).map_err(|_| {
-            io::Error::new(
-                io::ErrorKind::Other,
-                format!("Could not parse cached syntax set"),
-            )
+            io::Error::new(io::ErrorKind::Other, "Could not parse cached syntax set")
         })?;
         syntax_set.link_syntaxes();
 
@@ -70,12 +67,8 @@ impl HighlightingAssets {
                 theme_set_path.to_string_lossy()
             )
         })?;
-        let theme_set: ThemeSet = from_reader(theme_set_file).map_err(|_| {
-            io::Error::new(
-                io::ErrorKind::Other,
-                format!("Could not parse cached theme set"),
-            )
-        })?;
+        let theme_set: ThemeSet = from_reader(theme_set_file)
+            .map_err(|_| io::Error::new(io::ErrorKind::Other, "Could not parse cached theme set"))?;
 
         Ok(HighlightingAssets {
             syntax_set,
@@ -134,12 +127,10 @@ impl HighlightingAssets {
     }
 
     pub fn default_theme(&self) -> Result<&Theme> {
-        Ok(self.theme_set.themes.get("Default").ok_or_else(|| {
-            io::Error::new(
-                io::ErrorKind::Other,
-                format!("Could not find 'Default' theme"),
-            )
-        })?)
+        Ok(self.theme_set
+            .themes
+            .get("Default")
+            .ok_or_else(|| io::Error::new(io::ErrorKind::Other, "Could not find 'Default' theme"))?)
     }
 }
 

src/main.rs

@@ -22,7 +22,7 @@ mod diff;
 mod printer;
 mod terminal;
 
-use std::collections::{HashMap, HashSet};
+use std::collections::HashSet;
 use std::env;
 use std::fs::{self, File};
 use std::io::{self, BufRead, BufReader, Write};
@@ -257,7 +257,7 @@ fn print_file(
                 break;
             }
             Ok(_) => {
-                if !line_buffer.ends_with("\n") {
+                if !line_buffer.ends_with('\n') {
                     line_buffer.push('\n');
                 }
                 &line_buffer
@@ -459,14 +459,14 @@ fn run() -> Result<()> {
 
                 let longest = languages
                     .iter()
-                    .filter(|s| !s.hidden && s.file_extensions.len() > 0)
+                    .filter(|s| !s.hidden && !s.file_extensions.is_empty())
                     .map(|s| s.name.len())
                     .max()
                     .unwrap_or(32); // Fallback width if they have no language definitions.
 
                 let separator = " ";
                 for lang in languages {
-                    if lang.hidden || lang.file_extensions.len() == 0 {
+                    if lang.hidden || lang.file_extensions.is_empty() {
                         continue;
                     }
                     print!("{:width$}{}", lang.name, separator, width = longest);

src/printer.rs

@@ -92,7 +92,7 @@ impl<'a> Printer<'a> {
             decorations
                 .into_iter()
                 .filter_map(|dec| if grid_requested {
-                    Some(dec.unwrap_or(" ".to_owned()))
+                    Some(dec.unwrap_or_else(|| " ".to_owned()))
                 } else {
                     dec
                 })