fix trivial warnings without features

src/uu/basename/src/basename.rs

@@ -113,12 +113,8 @@ fn basename(fullname: &str, suffix: &str) -> String {
 
 fn strip_suffix(name: &str, suffix: &str) -> String {
     if name == suffix {
-        return name.to_owned();
+        name.to_owned()
+    } else {
+        name.strip_suffix(suffix).unwrap_or(name).to_owned()
     }
-
-    if name.ends_with(suffix) {
-        return name[..name.len() - suffix.len()].to_owned();
-    }
-
-    name.to_owned()
 }

src/uu/cp/src/cp.rs

@@ -547,14 +547,13 @@ impl FromStr for Attribute {
 }
 
 fn add_all_attributes() -> Vec<Attribute> {
-    let mut attr = Vec::new();
+    use Attribute::*;
+
+    let mut attr = vec![Ownership, Timestamps, Context, Xattr, Links];
+
     #[cfg(unix)]
-    attr.push(Attribute::Mode);
+    attr.insert(0, Mode);
-    attr.push(Attribute::Ownership);
+
-    attr.push(Attribute::Timestamps);
-    attr.push(Attribute::Context);
-    attr.push(Attribute::Xattr);
-    attr.push(Attribute::Links);
     attr
 }
 
@@ -714,7 +713,7 @@ fn parse_path_args(path_args: &[String], options: &Options) -> CopyResult<(Vec<S
 
 fn preserve_hardlinks(
     hard_links: &mut Vec<(String, u64)>,
-    source: &std::path::PathBuf,
+    source: &std::path::Path,
     dest: std::path::PathBuf,
     found_hard_link: &mut bool,
 ) -> CopyResult<()> {
@@ -1068,6 +1067,7 @@ fn copy_attribute(source: &Path, dest: &Path, attribute: &Attribute) -> CopyResu
 }
 
 #[cfg(not(windows))]
+#[allow(clippy::unnecessary_wraps)] // needed for windows version
 fn symlink_file(source: &Path, dest: &Path, context: &str) -> CopyResult<()> {
     match std::os::unix::fs::symlink(source, dest).context(context) {
         Ok(_) => Ok(()),

src/uu/cut/src/cut.rs

@@ -406,7 +406,7 @@ fn cut_files(mut filenames: Vec<String>, mode: Mode) -> i32 {
                 continue;
             }
 
-            if !path.metadata().is_ok() {
+            if path.metadata().is_err() {
                 show_error!("{}: No such file or directory", filename);
                 continue;
             }
@@ -487,7 +487,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                 .help("filter field columns from the input source")
                 .takes_value(true)
                 .allow_hyphen_values(true)
-                .value_name("LIST")                
+                .value_name("LIST")
                 .display_order(4),
         )
         .arg(
@@ -535,40 +535,36 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         matches.value_of(options::CHARACTERS),
         matches.value_of(options::FIELDS),
     ) {
-        (Some(byte_ranges), None, None) => {
+        (Some(byte_ranges), None, None) => list_to_ranges(byte_ranges, complement).map(|ranges| {
-            list_to_ranges(&byte_ranges[..], complement).map(|ranges| {
+            Mode::Bytes(
-                Mode::Bytes(
+                ranges,
-                    ranges,
+                Options {
-                    Options {
+                    out_delim: Some(
-                        out_delim: Some(
+                        matches
-                            matches
+                            .value_of(options::OUTPUT_DELIMITER)
-                                .value_of(options::OUTPUT_DELIMITER)
+                            .unwrap_or_default()
-                                .unwrap_or_default()
+                            .to_owned(),
-                                .to_owned(),
+                    ),
-                        ),
+                    zero_terminated: matches.is_present(options::ZERO_TERMINATED),
-                        zero_terminated: matches.is_present(options::ZERO_TERMINATED),
+                },
-                    },
+            )
-                )
+        }),
-            })
+        (None, Some(char_ranges), None) => list_to_ranges(char_ranges, complement).map(|ranges| {
-        }
+            Mode::Characters(
-        (None, Some(char_ranges), None) => {
+                ranges,
-            list_to_ranges(&char_ranges[..], complement).map(|ranges| {
+                Options {
-                Mode::Characters(
+                    out_delim: Some(
-                    ranges,
+                        matches
-                    Options {
+                            .value_of(options::OUTPUT_DELIMITER)
-                        out_delim: Some(
+                            .unwrap_or_default()
-                            matches
+                            .to_owned(),
-                                .value_of(options::OUTPUT_DELIMITER)
+                    ),
-                                .unwrap_or_default()
+                    zero_terminated: matches.is_present(options::ZERO_TERMINATED),
-                                .to_owned(),
+                },
-                        ),
+            )
-                        zero_terminated: matches.is_present(options::ZERO_TERMINATED),
+        }),
-                    },
-                )
-            })
-        }
         (None, None, Some(field_ranges)) => {
-            list_to_ranges(&field_ranges[..], complement).and_then(|ranges| {
+            list_to_ranges(field_ranges, complement).and_then(|ranges| {
                 let out_delim = match matches.value_of(options::OUTPUT_DELIMITER) {
                     Some(s) => {
                         if s.is_empty() {

src/uu/du/src/du.rs

@@ -322,7 +322,7 @@ fn convert_size_human(size: u64, multiplier: u64, _block_size: u64) -> String {
         }
     }
     if size == 0 {
-        return format!("0");
+        return "0".to_string();
     }
     format!("{}B", size)
 }

src/uu/expr/src/expr.rs

@@ -51,7 +51,7 @@ fn print_expr_error(expr_error: &str) -> ! {
     crash!(2, "{}", expr_error)
 }
 
-fn evaluate_ast(maybe_ast: Result<Box<syntax_tree::ASTNode>, String>) -> Result<String, String> {
+fn evaluate_ast(maybe_ast: Result<Box<syntax_tree::AstNode>, String>) -> Result<String, String> {
     if maybe_ast.is_err() {
         Err(maybe_ast.err().unwrap())
     } else {

src/uu/expr/src/syntax_tree.rs

@@ -17,10 +17,10 @@ use onig::{Regex, RegexOptions, Syntax};
 use crate::tokens::Token;
 
 type TokenStack = Vec<(usize, Token)>;
-pub type OperandsList = Vec<Box<ASTNode>>;
+pub type OperandsList = Vec<Box<AstNode>>;
 
 #[derive(Debug)]
-pub enum ASTNode {
+pub enum AstNode {
     Leaf {
         token_idx: usize,
         value: String,
@@ -31,7 +31,7 @@ pub enum ASTNode {
         operands: OperandsList,
     },
 }
-impl ASTNode {
+impl AstNode {
     fn debug_dump(&self) {
         self.debug_dump_impl(1);
     }
@@ -40,7 +40,7 @@ impl ASTNode {
             print!("\t",);
         }
         match *self {
-            ASTNode::Leaf {
+            AstNode::Leaf {
                 ref token_idx,
                 ref value,
             } => println!(
@@ -49,7 +49,7 @@ impl ASTNode {
                 token_idx,
                 self.evaluate()
             ),
-            ASTNode::Node {
+            AstNode::Node {
                 ref token_idx,
                 ref op_type,
                 ref operands,
@@ -67,23 +67,23 @@ impl ASTNode {
         }
     }
 
-    fn new_node(token_idx: usize, op_type: &str, operands: OperandsList) -> Box<ASTNode> {
+    fn new_node(token_idx: usize, op_type: &str, operands: OperandsList) -> Box<AstNode> {
-        Box::new(ASTNode::Node {
+        Box::new(AstNode::Node {
             token_idx,
             op_type: op_type.into(),
             operands,
         })
     }
-    fn new_leaf(token_idx: usize, value: &str) -> Box<ASTNode> {
+    fn new_leaf(token_idx: usize, value: &str) -> Box<AstNode> {
-        Box::new(ASTNode::Leaf {
+        Box::new(AstNode::Leaf {
             token_idx,
             value: value.into(),
         })
     }
     pub fn evaluate(&self) -> Result<String, String> {
         match *self {
-            ASTNode::Leaf { ref value, .. } => Ok(value.clone()),
+            AstNode::Leaf { ref value, .. } => Ok(value.clone()),
-            ASTNode::Node { ref op_type, .. } => match self.operand_values() {
+            AstNode::Node { ref op_type, .. } => match self.operand_values() {
                 Err(reason) => Err(reason),
                 Ok(operand_values) => match op_type.as_ref() {
                     "+" => infix_operator_two_ints(
@@ -161,7 +161,7 @@ impl ASTNode {
         }
     }
     pub fn operand_values(&self) -> Result<Vec<String>, String> {
-        if let ASTNode::Node { ref operands, .. } = *self {
+        if let AstNode::Node { ref operands, .. } = *self {
             let mut out = Vec::with_capacity(operands.len());
             for operand in operands {
                 match operand.evaluate() {
@@ -178,7 +178,7 @@ impl ASTNode {
 
 pub fn tokens_to_ast(
     maybe_tokens: Result<Vec<(usize, Token)>, String>,
-) -> Result<Box<ASTNode>, String> {
+) -> Result<Box<AstNode>, String> {
     if maybe_tokens.is_err() {
         Err(maybe_tokens.err().unwrap())
     } else {
@@ -212,7 +212,7 @@ pub fn tokens_to_ast(
     }
 }
 
-fn maybe_dump_ast(result: &Result<Box<ASTNode>, String>) {
+fn maybe_dump_ast(result: &Result<Box<AstNode>, String>) {
     use std::env;
     if let Ok(debug_var) = env::var("EXPR_DEBUG_AST") {
         if debug_var == "1" {
@@ -238,11 +238,11 @@ fn maybe_dump_rpn(rpn: &TokenStack) {
     }
 }
 
-fn ast_from_rpn(rpn: &mut TokenStack) -> Result<Box<ASTNode>, String> {
+fn ast_from_rpn(rpn: &mut TokenStack) -> Result<Box<AstNode>, String> {
     match rpn.pop() {
         None => Err("syntax error (premature end of expression)".to_owned()),
 
-        Some((token_idx, Token::Value { value })) => Ok(ASTNode::new_leaf(token_idx, &value)),
+        Some((token_idx, Token::Value { value })) => Ok(AstNode::new_leaf(token_idx, &value)),
 
         Some((token_idx, Token::InfixOp { value, .. })) => {
             maybe_ast_node(token_idx, &value, 2, rpn)
@@ -262,7 +262,7 @@ fn maybe_ast_node(
     op_type: &str,
     arity: usize,
     rpn: &mut TokenStack,
-) -> Result<Box<ASTNode>, String> {
+) -> Result<Box<AstNode>, String> {
     let mut operands = Vec::with_capacity(arity);
     for _ in 0..arity {
         match ast_from_rpn(rpn) {
@@ -271,7 +271,7 @@ fn maybe_ast_node(
         }
     }
     operands.reverse();
-    Ok(ASTNode::new_node(token_idx, op_type, operands))
+    Ok(AstNode::new_node(token_idx, op_type, operands))
 }
 
 fn move_rest_of_ops_to_out(

src/uu/fmt/src/parasplit.rs

@@ -267,7 +267,7 @@ impl<'a> ParagraphStream<'a> {
                 #[allow(clippy::match_like_matches_macro)]
                 // `matches!(...)` macro not stabilized until rust v1.42
                 l_slice[..colon_posn].chars().all(|x| match x as usize {
-                    y if y < 33 || y > 126 => false,
+                    y if !(33..=126).contains(&y) => false,
                     _ => true,
                 })
             }

src/uu/fold/src/fold.rs

@@ -66,7 +66,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                 .takes_value(true),
         )
         .arg(Arg::with_name(options::FILE).hidden(true).multiple(true))
-        .get_matches_from(args.clone());
+        .get_matches_from(args);
 
     let bytes = matches.is_present(options::BYTES);
     let spaces = matches.is_present(options::SPACES);

src/uu/head/src/head.rs

@@ -625,7 +625,7 @@ mod tests {
         assert_eq!(arg_outputs("head"), Ok("head".to_owned()));
     }
     #[test]
-    #[cfg(linux)]
+    #[cfg(target_os = "linux")]
     fn test_arg_iterate_bad_encoding() {
         let invalid = unsafe { std::str::from_utf8_unchecked(b"\x80\x81") };
         // this arises from a conversion from OsString to &str

src/uu/ln/src/ln.rs

@@ -303,7 +303,7 @@ fn exec(files: &[PathBuf], settings: &Settings) -> i32 {
     }
 }
 
-fn link_files_in_dir(files: &[PathBuf], target_dir: &PathBuf, settings: &Settings) -> i32 {
+fn link_files_in_dir(files: &[PathBuf], target_dir: &Path, settings: &Settings) -> i32 {
     if !target_dir.is_dir() {
         show_error!("target '{}' is not a directory", target_dir.display());
         return 1;
@@ -329,7 +329,7 @@ fn link_files_in_dir(files: &[PathBuf], target_dir: &PathBuf, settings: &Setting
                     };
                 }
             }
-            target_dir.clone()
+            target_dir.to_path_buf()
         } else {
             match srcpath.as_os_str().to_str() {
                 Some(name) => {
@@ -370,7 +370,7 @@ fn link_files_in_dir(files: &[PathBuf], target_dir: &PathBuf, settings: &Setting
     }
 }
 
-fn relative_path<'a>(src: &PathBuf, dst: &PathBuf) -> Result<Cow<'a, Path>> {
+fn relative_path<'a>(src: &Path, dst: &Path) -> Result<Cow<'a, Path>> {
     let abssrc = canonicalize(src, CanonicalizeMode::Normal)?;
     let absdst = canonicalize(dst, CanonicalizeMode::Normal)?;
     let suffix_pos = abssrc
@@ -390,7 +390,7 @@ fn relative_path<'a>(src: &PathBuf, dst: &PathBuf) -> Result<Cow<'a, Path>> {
     Ok(result.into())
 }
 
-fn link(src: &PathBuf, dst: &PathBuf, settings: &Settings) -> Result<()> {
+fn link(src: &Path, dst: &Path, settings: &Settings) -> Result<()> {
     let mut backup_path = None;
     let source: Cow<'_, Path> = if settings.relative {
         relative_path(&src, dst)?
@@ -453,13 +453,13 @@ fn read_yes() -> bool {
     }
 }
 
-fn simple_backup_path(path: &PathBuf, suffix: &str) -> PathBuf {
+fn simple_backup_path(path: &Path, suffix: &str) -> PathBuf {
     let mut p = path.as_os_str().to_str().unwrap().to_owned();
     p.push_str(suffix);
     PathBuf::from(p)
 }
 
-fn numbered_backup_path(path: &PathBuf) -> PathBuf {
+fn numbered_backup_path(path: &Path) -> PathBuf {
     let mut i: u64 = 1;
     loop {
         let new_path = simple_backup_path(path, &format!(".~{}~", i));
@@ -470,7 +470,7 @@ fn numbered_backup_path(path: &PathBuf) -> PathBuf {
     }
 }
 
-fn existing_backup_path(path: &PathBuf, suffix: &str) -> PathBuf {
+fn existing_backup_path(path: &Path, suffix: &str) -> PathBuf {
     let test_path = simple_backup_path(path, &".~1~".to_owned());
     if test_path.exists() {
         return numbered_backup_path(path);

src/uu/ls/src/ls.rs

@@ -1076,7 +1076,7 @@ fn should_display(entry: &DirEntry, config: &Config) -> bool {
     true
 }
 
-fn enter_directory(dir: &PathBuf, config: &Config) {
+fn enter_directory(dir: &Path, config: &Config) {
     let mut entries: Vec<_> = safe_unwrap!(fs::read_dir(dir).and_then(Iterator::collect));
 
     entries.retain(|e| should_display(e, config));
@@ -1101,7 +1101,7 @@ fn enter_directory(dir: &PathBuf, config: &Config) {
     }
 }
 
-fn get_metadata(entry: &PathBuf, config: &Config) -> std::io::Result<Metadata> {
+fn get_metadata(entry: &Path, config: &Config) -> std::io::Result<Metadata> {
     if config.dereference {
         entry.metadata().or_else(|_| entry.symlink_metadata())
     } else {
@@ -1109,7 +1109,7 @@ fn get_metadata(entry: &PathBuf, config: &Config) -> std::io::Result<Metadata> {
     }
 }
 
-fn display_dir_entry_size(entry: &PathBuf, config: &Config) -> (usize, usize) {
+fn display_dir_entry_size(entry: &Path, config: &Config) -> (usize, usize) {
     if let Ok(md) = get_metadata(entry, config) {
         (
             display_symlink_count(&md).len(),
@@ -1204,7 +1204,7 @@ fn display_grid(names: impl Iterator<Item = Cell>, width: u16, direction: Direct
 use uucore::fs::display_permissions;
 
 fn display_item_long(
-    item: &PathBuf,
+    item: &Path,
     strip: Option<&Path>,
     max_links: usize,
     max_size: usize,

src/uu/mv/src/mv.rs

@@ -335,7 +335,7 @@ fn exec(files: &[PathBuf], b: Behavior) -> i32 {
     0
 }
 
-fn move_files_into_dir(files: &[PathBuf], target_dir: &PathBuf, b: &Behavior) -> i32 {
+fn move_files_into_dir(files: &[PathBuf], target_dir: &Path, b: &Behavior) -> i32 {
     if !target_dir.is_dir() {
         show_error!("target ‘{}’ is not a directory", target_dir.display());
         return 1;
@@ -373,7 +373,7 @@ fn move_files_into_dir(files: &[PathBuf], target_dir: &PathBuf, b: &Behavior) ->
     }
 }
 
-fn rename(from: &PathBuf, to: &PathBuf, b: &Behavior) -> io::Result<()> {
+fn rename(from: &Path, to: &Path, b: &Behavior) -> io::Result<()> {
     let mut backup_path = None;
 
     if to.exists() {
@@ -429,7 +429,7 @@ fn rename(from: &PathBuf, to: &PathBuf, b: &Behavior) -> io::Result<()> {
 
 /// A wrapper around `fs::rename`, so that if it fails, we try falling back on
 /// copying and removing.
-fn rename_with_fallback(from: &PathBuf, to: &PathBuf) -> io::Result<()> {
+fn rename_with_fallback(from: &Path, to: &Path) -> io::Result<()> {
     if fs::rename(from, to).is_err() {
         // Get metadata without following symlinks
         let metadata = from.symlink_metadata()?;
@@ -464,7 +464,7 @@ fn rename_with_fallback(from: &PathBuf, to: &PathBuf) -> io::Result<()> {
 /// Move the given symlink to the given destination. On Windows, dangling
 /// symlinks return an error.
 #[inline]
-fn rename_symlink_fallback(from: &PathBuf, to: &PathBuf) -> io::Result<()> {
+fn rename_symlink_fallback(from: &Path, to: &Path) -> io::Result<()> {
     let path_symlink_points_to = fs::read_link(from)?;
     #[cfg(unix)]
     {
@@ -507,20 +507,20 @@ fn read_yes() -> bool {
     }
 }
 
-fn simple_backup_path(path: &PathBuf, suffix: &str) -> PathBuf {
+fn simple_backup_path(path: &Path, suffix: &str) -> PathBuf {
     let mut p = path.to_string_lossy().into_owned();
     p.push_str(suffix);
     PathBuf::from(p)
 }
 
-fn numbered_backup_path(path: &PathBuf) -> PathBuf {
+fn numbered_backup_path(path: &Path) -> PathBuf {
     (1_u64..)
         .map(|i| path.with_extension(format!("~{}~", i)))
         .find(|p| !p.exists())
         .expect("cannot create backup")
 }
 
-fn existing_backup_path(path: &PathBuf, suffix: &str) -> PathBuf {
+fn existing_backup_path(path: &Path, suffix: &str) -> PathBuf {
     let test_path = path.with_extension("~1~");
     if test_path.exists() {
         numbered_backup_path(path)
@@ -529,7 +529,7 @@ fn existing_backup_path(path: &PathBuf, suffix: &str) -> PathBuf {
     }
 }
 
-fn is_empty_dir(path: &PathBuf) -> bool {
+fn is_empty_dir(path: &Path) -> bool {
     match fs::read_dir(path) {
         Ok(contents) => contents.peekable().peek().is_none(),
         Err(_e) => false,

src/uu/od/src/od.rs

@@ -118,7 +118,7 @@ struct OdOptions {
 }
 
 impl OdOptions {
-    fn new<'a>(matches: ArgMatches<'a>, args: Vec<String>) -> Result<OdOptions, String> {
+    fn new(matches: ArgMatches, args: Vec<String>) -> Result<OdOptions, String> {
         let byte_order = match matches.value_of(options::ENDIAN) {
             None => ByteOrder::Native,
             Some("little") => ByteOrder::Little,

src/uu/od/src/parse_inputs.rs

@@ -63,7 +63,7 @@ pub fn parse_inputs(matches: &dyn CommandLineOpts) -> Result<CommandLineInputs,
                 }
                 if input_strings.len() == 2 {
                     return Ok(CommandLineInputs::FileAndOffset((
-                        input_strings[0].clone().to_owned(),
+                        input_strings[0].to_string(),
                         n,
                         None,
                     )));
@@ -106,7 +106,7 @@ pub fn parse_inputs_traditional(input_strings: Vec<&str>) -> Result<CommandLineI
                     Some(m),
                 ))),
                 (_, Ok(m)) => Ok(CommandLineInputs::FileAndOffset((
-                    input_strings[0].clone().to_owned(),
+                    input_strings[0].to_string(),
                     m,
                     None,
                 ))),
@@ -118,7 +118,7 @@ pub fn parse_inputs_traditional(input_strings: Vec<&str>) -> Result<CommandLineI
             let label = parse_offset_operand(&input_strings[2]);
             match (offset, label) {
                 (Ok(n), Ok(m)) => Ok(CommandLineInputs::FileAndOffset((
-                    input_strings[0].clone().to_owned(),
+                    input_strings[0].to_string(),
                     n,
                     Some(m),
                 ))),

src/uu/printf/src/tokenize/num_format/formatters/base_conv/mod.rs

@@ -199,8 +199,7 @@ pub fn arrnum_int_add(arrnum: &[u8], basenum: u8, base_ten_int_term: u8) -> Vec<
 }
 
 pub fn base_conv_vec(src: &[u8], radix_src: u8, radix_dest: u8) -> Vec<u8> {
-    let mut result: Vec<u8> = Vec::new();
+    let mut result = vec![0];
-    result.push(0);
     for i in src {
         result = arrnum_int_mult(&result, radix_dest, radix_src);
         result = arrnum_int_add(&result, radix_dest, *i);
@@ -226,8 +225,7 @@ pub fn base_conv_float(src: &[u8], radix_src: u8, radix_dest: u8) -> f64 {
     // to implement this for arbitrary string input.
     // until then, the below operates as an outline
     // of how it would work.
-    let mut result: Vec<u8> = Vec::new();
+    let result: Vec<u8> = vec![0];
-    result.push(0);
     let mut factor: f64 = 1_f64;
     let radix_src_float: f64 = f64::from(radix_src);
     let mut r: f64 = 0_f64;

src/uu/readlink/src/readlink.rs

@@ -13,7 +13,7 @@ extern crate uucore;
 use clap::{App, Arg};
 use std::fs;
 use std::io::{stdout, Write};
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use uucore::fs::{canonicalize, CanonicalizeMode};
 
 const NAME: &str = "readlink";
@@ -160,8 +160,8 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     0
 }
 
-fn show(path: &PathBuf, no_newline: bool, use_zero: bool) {
+fn show(path: &Path, no_newline: bool, use_zero: bool) {
-    let path = path.as_path().to_str().unwrap();
+    let path = path.to_str().unwrap();
     if use_zero {
         print!("{}\0", path);
     } else if no_newline {

src/uu/realpath/src/realpath.rs

@@ -12,7 +12,7 @@ extern crate uucore;
 
 use clap::{App, Arg};
 use std::fs;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 use uucore::fs::{canonicalize, CanonicalizeMode};
 
 static ABOUT: &str = "print the resolved path";
@@ -82,7 +82,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     retcode
 }
 
-fn resolve_path(p: &PathBuf, strip: bool, zero: bool, quiet: bool) -> bool {
+fn resolve_path(p: &Path, strip: bool, zero: bool, quiet: bool) -> bool {
     let abs = canonicalize(p, CanonicalizeMode::Normal).unwrap();
 
     if strip {

src/uu/rm/src/rm.rs

@@ -176,7 +176,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
                 } else if matches.is_present(OPT_PROMPT_MORE) {
                     InteractiveMode::Once
                 } else if matches.is_present(OPT_INTERACTIVE) {
-                    match &matches.value_of(OPT_INTERACTIVE).unwrap()[..] {
+                    match matches.value_of(OPT_INTERACTIVE).unwrap() {
                         "none" => InteractiveMode::None,
                         "once" => InteractiveMode::Once,
                         "always" => InteractiveMode::Always,

src/uu/seq/src/seq.rs

@@ -102,7 +102,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
     let mut largest_dec = 0;
     let mut padding = 0;
     let first = if numbers.len() > 1 {
-        let slice = &numbers[0][..];
+        let slice = numbers[0];
         let len = slice.len();
         let dec = slice.find('.').unwrap_or(len);
         largest_dec = len - dec;
@@ -118,7 +118,7 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         1.0
     };
     let increment = if numbers.len() > 2 {
-        let slice = &numbers[1][..];
+        let slice = numbers[1];
         let len = slice.len();
         let dec = slice.find('.').unwrap_or(len);
         largest_dec = cmp::max(largest_dec, len - dec);
@@ -134,11 +134,11 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         1.0
     };
     if increment == 0.0 {
-        show_error!("increment value: '{}'", &numbers[1][..]);
+        show_error!("increment value: '{}'", numbers[1]);
         return 1;
     }
     let last = {
-        let slice = &numbers[numbers.len() - 1][..];
+        let slice = numbers[numbers.len() - 1];
         padding = cmp::max(padding, slice.find('.').unwrap_or_else(|| slice.len()));
         match parse_float(slice) {
             Ok(n) => n,

src/uu/shred/src/shred.rs

@@ -439,6 +439,7 @@ fn pass_name(pass_type: PassType) -> String {
     }
 }
 
+#[allow(clippy::too_many_arguments)]
 fn wipe_file(
     path_str: &str,
     n_passes: usize,
@@ -472,12 +473,9 @@ fn wipe_file(
 
         let mut perms = metadata.permissions();
         perms.set_readonly(false);
-        match fs::set_permissions(path, perms) {
+        if let Err(e) = fs::set_permissions(path, perms) {
-            Err(e) => {
+            show_error!("{}", e);
-                show_error!("{}", e);
+            return;
-                return;
-            }
-            _ => {}
         }
     }
 

src/uu/sum/src/sum.rs

@@ -75,7 +75,7 @@ fn open(name: &str) -> Result<Box<dyn Read>> {
                     "Is a directory",
                 ));
             };
-            if !path.metadata().is_ok() {
+            if path.metadata().is_err() {
                 return Err(std::io::Error::new(
                     std::io::ErrorKind::NotFound,
                     "No such file or directory",

src/uu/tac/src/tac.rs

@@ -90,7 +90,7 @@ fn tac(filenames: Vec<String>, before: bool, _: bool, separator: &str) -> i32 {
             Box::new(stdin()) as Box<dyn Read>
         } else {
             let path = Path::new(filename);
-            if path.is_dir() || !path.metadata().is_ok() {
+            if path.is_dir() || path.metadata().is_err() {
                 show_error!(
                     "failed to open '{}' for reading: No such file or directory",
                     filename

src/uu/test/src/test.rs

@@ -55,16 +55,16 @@ fn two(args: &[&[u8]], error: &mut bool) -> bool {
         b"-d" => path(args[1], PathCondition::Directory),
         b"-e" => path(args[1], PathCondition::Exists),
         b"-f" => path(args[1], PathCondition::Regular),
-        b"-g" => path(args[1], PathCondition::GroupIDFlag),
+        b"-g" => path(args[1], PathCondition::GroupIdFlag),
         b"-h" => path(args[1], PathCondition::SymLink),
         b"-L" => path(args[1], PathCondition::SymLink),
         b"-n" => one(&args[1..]),
-        b"-p" => path(args[1], PathCondition::FIFO),
+        b"-p" => path(args[1], PathCondition::Fifo),
         b"-r" => path(args[1], PathCondition::Readable),
         b"-S" => path(args[1], PathCondition::Socket),
         b"-s" => path(args[1], PathCondition::NonEmpty),
         b"-t" => isatty(args[1]),
-        b"-u" => path(args[1], PathCondition::UserIDFlag),
+        b"-u" => path(args[1], PathCondition::UserIdFlag),
         b"-w" => path(args[1], PathCondition::Writable),
         b"-x" => path(args[1], PathCondition::Executable),
         b"-z" => !one(&args[1..]),
@@ -322,13 +322,13 @@ enum PathCondition {
     Directory,
     Exists,
     Regular,
-    GroupIDFlag,
+    GroupIdFlag,
     SymLink,
-    FIFO,
+    Fifo,
     Readable,
     Socket,
     NonEmpty,
-    UserIDFlag,
+    UserIdFlag,
     Writable,
     Executable,
 }
@@ -390,13 +390,13 @@ fn path(path: &[u8], cond: PathCondition) -> bool {
         PathCondition::Directory => file_type.is_dir(),
         PathCondition::Exists => true,
         PathCondition::Regular => file_type.is_file(),
-        PathCondition::GroupIDFlag => metadata.mode() & S_ISGID != 0,
+        PathCondition::GroupIdFlag => metadata.mode() & S_ISGID != 0,
         PathCondition::SymLink => metadata.file_type().is_symlink(),
-        PathCondition::FIFO => file_type.is_fifo(),
+        PathCondition::Fifo => file_type.is_fifo(),
         PathCondition::Readable => perm(metadata, Permission::Read),
         PathCondition::Socket => file_type.is_socket(),
         PathCondition::NonEmpty => metadata.size() > 0,
-        PathCondition::UserIDFlag => metadata.mode() & S_ISUID != 0,
+        PathCondition::UserIdFlag => metadata.mode() & S_ISUID != 0,
         PathCondition::Writable => perm(metadata, Permission::Write),
         PathCondition::Executable => perm(metadata, Permission::Execute),
     }
@@ -416,13 +416,13 @@ fn path(path: &[u8], cond: PathCondition) -> bool {
         PathCondition::Directory => stat.is_dir(),
         PathCondition::Exists => true,
         PathCondition::Regular => stat.is_file(),
-        PathCondition::GroupIDFlag => false,
+        PathCondition::GroupIdFlag => false,
         PathCondition::SymLink => false,
-        PathCondition::FIFO => false,
+        PathCondition::Fifo => false,
         PathCondition::Readable => false, // TODO
         PathCondition::Socket => false,
         PathCondition::NonEmpty => stat.len() > 0,
-        PathCondition::UserIDFlag => false,
+        PathCondition::UserIdFlag => false,
         PathCondition::Writable => false,   // TODO
         PathCondition::Executable => false, // TODO
     }

src/uu/tr/src/expand.rs

@@ -24,7 +24,7 @@ use std::ops::RangeInclusive;
 fn parse_sequence(s: &str) -> (char, usize) {
     let c = s.chars().next().expect("invalid escape: empty string");
 
-    if '0' <= c && c <= '7' {
+    if ('0'..='7').contains(&c) {
         let mut v = c.to_digit(8).unwrap();
         let mut consumed = 1;
         let bits_per_digit = 3;

src/uu/tsort/src/tsort.rs

@@ -16,8 +16,8 @@ use std::io::{stdin, BufRead, BufReader, Read};
 use std::path::Path;
 
 static VERSION: &str = env!("CARGO_PKG_VERSION");
-static SUMMARY: &str = "Topological sort the strings in FILE. 
+static SUMMARY: &str = "Topological sort the strings in FILE.
-Strings are defined as any sequence of tokens separated by whitespace (tab, space, or newline). 
+Strings are defined as any sequence of tokens separated by whitespace (tab, space, or newline).
 If FILE is not passed in, stdin is used instead.";
 static USAGE: &str = "tsort [OPTIONS] FILE";
 
@@ -32,13 +32,16 @@ pub fn uumain(args: impl uucore::Args) -> i32 {
         .version(VERSION)
         .usage(USAGE)
         .about(SUMMARY)
-        .arg(Arg::with_name(options::FILE).hidden(true))
+        .arg(
+            Arg::with_name(options::FILE)
+                .default_value("-")
+                .hidden(true),
+        )
         .get_matches_from(args);
 
-    let input = match matches.value_of(options::FILE) {
+    let input = matches
-        Some(v) => v,
+        .value_of(options::FILE)
-        None => "-",
+        .expect("Value is required by clap");
-    };
 
     let mut stdin_buf;
     let mut file_buf;

src/uu/wc/src/count_bytes.rs

@@ -72,30 +72,27 @@ pub(crate) fn count_bytes_fast<T: WordCountable>(handle: &mut T) -> WcResult<usi
     #[cfg(unix)]
     {
         let fd = handle.as_raw_fd();
-        match fstat(fd) {
+        if let Ok(stat) = fstat(fd) {
-            Ok(stat) => {
+            // If the file is regular, then the `st_size` should hold
-                // If the file is regular, then the `st_size` should hold
+            // the file's size in bytes.
-                // the file's size in bytes.
+            if (stat.st_mode & S_IFREG) != 0 {
-                if (stat.st_mode & S_IFREG) != 0 {
+                return Ok(stat.st_size as usize);
-                    return Ok(stat.st_size as usize);
+            }
-                }
+            #[cfg(any(target_os = "linux", target_os = "android"))]
-                #[cfg(any(target_os = "linux", target_os = "android"))]
+            {
-                {
+                // Else, if we're on Linux and our file is a FIFO pipe
-                    // Else, if we're on Linux and our file is a FIFO pipe
+                // (or stdin), we use splice to count the number of bytes.
-                    // (or stdin), we use splice to count the number of bytes.
+                if (stat.st_mode & S_IFIFO) != 0 {
-                    if (stat.st_mode & S_IFIFO) != 0 {
+                    if let Ok(n) = count_bytes_using_splice(fd) {
-                        if let Ok(n) = count_bytes_using_splice(fd) {
+                        return Ok(n);
-                            return Ok(n);
-                        }
                     }
                 }
             }
-            _ => {}
         }
     }
 
     // Fall back on `read`, but without the overhead of counting words and lines.
-    let mut buf = [0 as u8; BUF_SIZE];
+    let mut buf = [0_u8; BUF_SIZE];
     let mut byte_count = 0;
     loop {
         match handle.read(&mut buf) {

src/uu/wc/src/wc.rs

@@ -138,11 +138,8 @@ impl AddAssign for WordCount {
 }
 
 impl WordCount {
-    fn with_title<'a>(self, title: &'a str) -> TitledWordCount<'a> {
+    fn with_title(self, title: &str) -> TitledWordCount {
-        return TitledWordCount {
+        TitledWordCount { title, count: self }
-            title: title,
-            count: self,
-        };
     }
 }
 
@@ -251,7 +248,7 @@ fn is_word_separator(byte: u8) -> bool {
 fn word_count_from_reader<T: WordCountable>(
     mut reader: T,
     settings: &Settings,
-    path: &String,
+    path: &str,
 ) -> WcResult<WordCount> {
     let only_count_bytes = settings.show_bytes
         && (!(settings.show_chars
@@ -333,18 +330,18 @@ fn word_count_from_reader<T: WordCountable>(
     })
 }
 
-fn word_count_from_path(path: &String, settings: &Settings) -> WcResult<WordCount> {
+fn word_count_from_path(path: &str, settings: &Settings) -> WcResult<WordCount> {
     if path == "-" {
         let stdin = io::stdin();
         let stdin_lock = stdin.lock();
-        return Ok(word_count_from_reader(stdin_lock, settings, path)?);
+        word_count_from_reader(stdin_lock, settings, path)
     } else {
         let path_obj = Path::new(path);
         if path_obj.is_dir() {
-            return Err(WcError::IsDirectory(path.clone()));
+            Err(WcError::IsDirectory(path.to_owned()))
         } else {
             let file = File::open(path)?;
-            return Ok(word_count_from_reader(file, settings, path)?);
+            word_count_from_reader(file, settings, path)
         }
     }
 }
@@ -425,7 +422,7 @@ fn print_stats(
     }
 
     if result.title == "-" {
-        writeln!(stdout_lock, "")?;
+        writeln!(stdout_lock)?;
     } else {
         writeln!(stdout_lock, " {}", result.title)?;
     }