Apply clippy lint fixes

src/attr.rs

@@ -260,7 +260,7 @@ impl Rewrite for ast::MetaItemInner {
 fn has_newlines_before_after_comment(comment: &str) -> (&str, &str) {
     // Look at before and after comment and see if there are any empty lines.
     let comment_begin = comment.find('/');
-    let len = comment_begin.unwrap_or_else(|| comment.len());
+    let len = comment_begin.unwrap_or(comment.len());
     let mlb = count_newlines(&comment[..len]) > 1;
     let mla = if comment_begin.is_none() {
         mlb

src/bin/main.rs

@@ -746,8 +746,7 @@ impl CliOptions for GetOptsOptions {
     fn version(&self) -> Option<Version> {
         self.inline_config
             .get("version")
-            .map(|version| Version::from_str(version).ok())
-            .flatten()
+            .and_then(|version| Version::from_str(version).ok())
     }
 }
 
@@ -818,7 +817,7 @@ mod test {
         options.inline_config = HashMap::from([("version".to_owned(), "Two".to_owned())]);
         let config = get_config(None, Some(options));
         assert_eq!(config.style_edition(), StyleEdition::Edition2024);
-        assert_eq!(config.overflow_delimited_expr(), true);
+        assert!(config.overflow_delimited_expr());
     }
 
     #[nightly_only_test]
@@ -828,7 +827,7 @@ mod test {
         let config_file = Some(Path::new("tests/config/style-edition/just-version"));
         let config = get_config(config_file, Some(options));
         assert_eq!(config.style_edition(), StyleEdition::Edition2024);
-        assert_eq!(config.overflow_delimited_expr(), true);
+        assert!(config.overflow_delimited_expr());
     }
 
     #[nightly_only_test]
@@ -873,7 +872,7 @@ mod test {
         ]);
         let config = get_config(None, Some(options));
         assert_eq!(config.style_edition(), StyleEdition::Edition2024);
-        assert_eq!(config.overflow_delimited_expr(), true);
+        assert!(config.overflow_delimited_expr());
     }
 
     #[nightly_only_test]
@@ -939,7 +938,7 @@ mod test {
         options.style_edition = Some(StyleEdition::Edition2024);
         let config = get_config(None, Some(options));
         assert_eq!(config.style_edition(), StyleEdition::Edition2024);
-        assert_eq!(config.overflow_delimited_expr(), true);
+        assert!(config.overflow_delimited_expr());
     }
 
     #[nightly_only_test]
@@ -949,7 +948,7 @@ mod test {
         let config_file = Some(Path::new("tests/config/style-edition/overrides"));
         let config = get_config(config_file, Some(options));
         assert_eq!(config.style_edition(), StyleEdition::Edition2024);
-        assert_eq!(config.overflow_delimited_expr(), false);
+        assert!(!config.overflow_delimited_expr());
     }
 
     #[nightly_only_test]
@@ -961,6 +960,6 @@ mod test {
             HashMap::from([("overflow_delimited_expr".to_owned(), "false".to_owned())]);
         let config = get_config(config_file, Some(options));
         assert_eq!(config.style_edition(), StyleEdition::Edition2024);
-        assert_eq!(config.overflow_delimited_expr(), false);
+        assert!(!config.overflow_delimited_expr());
     }
 }

src/chains.rs

@@ -213,7 +213,7 @@ impl ChainItemKind {
     fn is_tup_field_access(expr: &ast::Expr) -> bool {
         match expr.kind {
             ast::ExprKind::Field(_, ref field) => {
-                field.name.as_str().chars().all(|c| c.is_digit(10))
+                field.name.as_str().chars().all(|c| c.is_ascii_digit())
             }
             _ => false,
         }
@@ -288,7 +288,7 @@ impl Rewrite for ChainItem {
             ChainItemKind::Parent {
                 ref expr,
                 parens: true,
-            } => crate::expr::rewrite_paren(context, &expr, shape, expr.span)?,
+            } => crate::expr::rewrite_paren(context, expr, shape, expr.span)?,
             ChainItemKind::Parent {
                 ref expr,
                 parens: false,
@@ -353,7 +353,7 @@ impl ChainItem {
             format!("::<{}>", type_list.join(", "))
         };
         let callee_str = format!(".{}{}", rewrite_ident(context, method_name), type_str);
-        rewrite_call(context, &callee_str, &args, span, shape)
+        rewrite_call(context, &callee_str, args, span, shape)
     }
 }
 
@@ -843,7 +843,7 @@ impl<'a> ChainFormatterBlock<'a> {
     }
 }
 
-impl<'a> ChainFormatter for ChainFormatterBlock<'a> {
+impl ChainFormatter for ChainFormatterBlock<'_> {
     fn format_root(
         &mut self,
         parent: &ChainItem,
@@ -931,7 +931,7 @@ impl<'a> ChainFormatterVisual<'a> {
     }
 }
 
-impl<'a> ChainFormatter for ChainFormatterVisual<'a> {
+impl ChainFormatter for ChainFormatterVisual<'_> {
     fn format_root(
         &mut self,
         parent: &ChainItem,

src/closures.rs

@@ -124,9 +124,10 @@ fn needs_block(
     prefix: &str,
     context: &RewriteContext<'_>,
 ) -> bool {
-    let has_attributes = block.stmts.first().map_or(false, |first_stmt| {
-        !get_attrs_from_stmt(first_stmt).is_empty()
-    });
+    let has_attributes = block
+        .stmts
+        .first()
+        .is_some_and(|first_stmt| !get_attrs_from_stmt(first_stmt).is_empty());
 
     is_unsafe_block(block)
         || block.stmts.len() > 1
@@ -434,9 +435,8 @@ pub(crate) fn rewrite_last_closure(
 
         // When overflowing the closure which consists of a single control flow expression,
         // force to use block if its condition uses multi line.
-        let is_multi_lined_cond = rewrite_cond(context, body, body_shape).map_or(false, |cond| {
-            cond.contains('\n') || cond.len() > body_shape.width
-        });
+        let is_multi_lined_cond = rewrite_cond(context, body, body_shape)
+            .is_some_and(|cond| cond.contains('\n') || cond.len() > body_shape.width);
         if is_multi_lined_cond {
             return rewrite_closure_with_block(body, &prefix, context, body_shape);
         }

src/comment.rs

@@ -990,11 +990,11 @@ fn is_table_item(mut s: &str) -> bool {
     // This function may return false positive, but should get its job done in most cases (i.e.
     // markdown tables with two column delimiters).
     s = s.trim_start();
-    return s.starts_with('|')
+    s.starts_with('|')
         && match s.rfind('|') {
             Some(0) | None => false,
             _ => true,
-        };
+        }
 }
 
 /// Given the span, rewrite the missing comment inside it if available.
@@ -1521,7 +1521,7 @@ impl<'a> LineClasses<'a> {
     }
 }
 
-impl<'a> Iterator for LineClasses<'a> {
+impl Iterator for LineClasses<'_> {
     type Item = (FullCodeCharKind, String);
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -1797,7 +1797,7 @@ impl<'a> CommentReducer<'a> {
     }
 }
 
-impl<'a> Iterator for CommentReducer<'a> {
+impl Iterator for CommentReducer<'_> {
     type Item = char;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -2007,10 +2007,10 @@ mod test {
 
     #[test]
     fn test_contains_comment() {
-        assert_eq!(contains_comment("abc"), false);
-        assert_eq!(contains_comment("abc // qsdf"), true);
-        assert_eq!(contains_comment("abc /* kqsdf"), true);
-        assert_eq!(contains_comment("abc \" /* */\" qsdf"), false);
+        assert!(!contains_comment("abc"));
+        assert!(contains_comment("abc // qsdf"));
+        assert!(contains_comment("abc /* kqsdf"));
+        assert!(!contains_comment("abc \" /* */\" qsdf"));
     }
 
     #[test]

src/config/file_lines.rs

@@ -163,7 +163,7 @@ impl fmt::Display for FileLines {
             Some(map) => {
                 for (file_name, ranges) in map.iter() {
                     write!(f, "{file_name}: ")?;
-                    write!(f, "{}\n", ranges.iter().format(", "))?;
+                    writeln!(f, "{}", ranges.iter().format(", "))?;
                 }
             }
         };

src/config/mod.rs

@@ -327,7 +327,7 @@ impl Config {
         style_edition: Option<StyleEdition>,
         version: Option<Version>,
     ) -> Result<Config, Error> {
-        let mut file = File::open(&file_path)?;
+        let mut file = File::open(file_path)?;
         let mut toml = String::new();
         file.read_to_string(&mut toml)?;
         Config::from_toml_for_style_edition(&toml, file_path, edition, style_edition, version)
@@ -715,8 +715,8 @@ mod test {
     fn test_was_set() {
         let config = Config::from_toml("hard_tabs = true", Path::new("./rustfmt.toml")).unwrap();
 
-        assert_eq!(config.was_set().hard_tabs(), true);
-        assert_eq!(config.was_set().verbose(), false);
+        assert!(config.was_set().hard_tabs());
+        assert!(!config.was_set().verbose());
     }
 
     const PRINT_DOCS_STABLE_OPTION: &str = "stable_option <boolean> Default: false";
@@ -732,9 +732,9 @@ mod test {
         Config::print_docs(&mut output, false);
 
         let s = str::from_utf8(&output).unwrap();
-        assert_eq!(s.contains(PRINT_DOCS_STABLE_OPTION), true);
-        assert_eq!(s.contains(PRINT_DOCS_UNSTABLE_OPTION), false);
-        assert_eq!(s.contains(PRINT_DOCS_PARTIALLY_UNSTABLE_OPTION), true);
+        assert!(s.contains(PRINT_DOCS_STABLE_OPTION));
+        assert!(!s.contains(PRINT_DOCS_UNSTABLE_OPTION));
+        assert!(s.contains(PRINT_DOCS_PARTIALLY_UNSTABLE_OPTION));
     }
 
     #[test]
@@ -745,9 +745,9 @@ mod test {
         Config::print_docs(&mut output, true);
 
         let s = str::from_utf8(&output).unwrap();
-        assert_eq!(s.contains(PRINT_DOCS_STABLE_OPTION), true);
-        assert_eq!(s.contains(PRINT_DOCS_UNSTABLE_OPTION), true);
-        assert_eq!(s.contains(PRINT_DOCS_PARTIALLY_UNSTABLE_OPTION), true);
+        assert!(s.contains(PRINT_DOCS_STABLE_OPTION));
+        assert!(s.contains(PRINT_DOCS_UNSTABLE_OPTION));
+        assert!(s.contains(PRINT_DOCS_PARTIALLY_UNSTABLE_OPTION));
     }
 
     #[test]
@@ -966,32 +966,32 @@ make_backup = false
         config.set().unstable_features(true);
         // When we don't set the config from toml or command line options it
         // doesn't get marked as set by the user.
-        assert_eq!(config.was_set().unstable_features(), false);
+        assert!(!config.was_set().unstable_features());
         config.set().unstable_features(true);
-        assert_eq!(config.unstable_features(), true);
+        assert!(config.unstable_features());
     }
 
     #[nightly_only_test]
     #[test]
     fn test_unstable_from_toml() {
         let config =
             Config::from_toml("unstable_features = true", Path::new("./rustfmt.toml")).unwrap();
-        assert_eq!(config.was_set().unstable_features(), true);
-        assert_eq!(config.unstable_features(), true);
+        assert!(config.was_set().unstable_features());
+        assert!(config.unstable_features());
     }
 
     #[test]
     fn test_set_cli() {
         let mut config = Config::default();
-        assert_eq!(config.was_set().edition(), false);
-        assert_eq!(config.was_set_cli().edition(), false);
+        assert!(!config.was_set().edition());
+        assert!(!config.was_set_cli().edition());
         config.set().edition(Edition::Edition2021);
-        assert_eq!(config.was_set().edition(), false);
-        assert_eq!(config.was_set_cli().edition(), false);
+        assert!(!config.was_set().edition());
+        assert!(!config.was_set_cli().edition());
         config.set_cli().edition(Edition::Edition2021);
-        assert_eq!(config.was_set().edition(), false);
-        assert_eq!(config.was_set_cli().edition(), true);
-        assert_eq!(config.was_set_cli().emit_mode(), false);
+        assert!(!config.was_set().edition());
+        assert!(config.was_set_cli().edition());
+        assert!(!config.was_set_cli().emit_mode());
     }
 
     #[cfg(test)]
@@ -1365,7 +1365,7 @@ make_backup = false
             let versions = vec!["0.0.0", "0.0.1", "0.1.0"];
 
             for version in versions {
-                let toml = format!("required_version=\"{}\"", version.to_string());
+                let toml = format!("required_version=\"{}\"", version);
                 let config = Config::from_toml(&toml, Path::new("./rustfmt.toml")).unwrap();
 
                 assert!(!config.version_meets_requirement());
@@ -1389,8 +1389,7 @@ make_backup = false
             for minor in current_version.minor..0 {
                 let toml = format!(
                     "required_version=\"^{}.{}.0\"",
-                    current_version.major.to_string(),
-                    minor.to_string()
+                    current_version.major, minor
                 );
                 let config = Config::from_toml(&toml, Path::new("./rustfmt.toml")).unwrap();
 
@@ -1434,7 +1433,7 @@ make_backup = false
         #[nightly_only_test]
         #[test]
         fn test_required_version_exact_boundary() {
-            let toml = format!("required_version=\"{}\"", get_current_version().to_string());
+            let toml = format!("required_version=\"{}\"", get_current_version());
             let config = Config::from_toml(&toml, Path::new("./rustfmt.toml")).unwrap();
 
             assert!(config.version_meets_requirement());
@@ -1443,10 +1442,7 @@ make_backup = false
         #[nightly_only_test]
         #[test]
         fn test_required_version_pre_release() {
-            let toml = format!(
-                "required_version=\"^{}-alpha\"",
-                get_current_version().to_string()
-            );
+            let toml = format!("required_version=\"^{}-alpha\"", get_current_version());
             let config = Config::from_toml(&toml, Path::new("./rustfmt.toml")).unwrap();
 
             assert!(config.version_meets_requirement());
@@ -1455,10 +1451,7 @@ make_backup = false
         #[nightly_only_test]
         #[test]
         fn test_required_version_with_build_metadata() {
-            let toml = format!(
-                "required_version=\"{}+build.1\"",
-                get_current_version().to_string()
-            );
+            let toml = format!("required_version=\"{}+build.1\"", get_current_version());
 
             let config = Config::from_toml(&toml, Path::new("./rustfmt.toml")).unwrap();
 

src/config/options.rs

@@ -170,9 +170,11 @@ pub enum ReportTactic {
 
 /// What Rustfmt should emit. Mostly corresponds to the `--emit` command line
 /// option.
+#[derive(Default)]
 #[config_type]
 pub enum EmitMode {
     /// Emits to files.
+    #[default]
     Files,
     /// Writes the output to stdout.
     Stdout,
@@ -325,12 +327,6 @@ impl ::std::str::FromStr for WidthHeuristics {
     }
 }
 
-impl Default for EmitMode {
-    fn default() -> EmitMode {
-        EmitMode::Files
-    }
-}
-
 /// A set of directories, files and modules that rustfmt should ignore.
 #[derive(Default, Clone, Debug, PartialEq)]
 pub struct IgnoreList {
@@ -440,11 +436,13 @@ pub trait CliOptions {
 }
 
 /// The edition of the syntax and semantics of code (RFC 2052).
+#[derive(Default)]
 #[config_type]
 pub enum Edition {
     #[value = "2015"]
     #[doc_hint = "2015"]
     /// Edition 2015.
+    #[default]
     Edition2015,
     #[value = "2018"]
     #[doc_hint = "2018"]
@@ -460,12 +458,6 @@ pub enum Edition {
     Edition2024,
 }
 
-impl Default for Edition {
-    fn default() -> Edition {
-        Edition::Edition2015
-    }
-}
-
 impl From<Edition> for rustc_span::edition::Edition {
     fn from(edition: Edition) -> Self {
         match edition {