clippy: autofix some lint warnings

build.rs

@@ -40,15 +40,15 @@ fn channel() -> String {
 
 fn commit_hash() -> Option<String> {
     Command::new("git")
-        .args(&["rev-parse", "--short", "HEAD"])
+        .args(["rev-parse", "--short", "HEAD"])
         .output()
         .ok()
         .and_then(|r| String::from_utf8(r.stdout).ok())
 }
 
 fn commit_date() -> Option<String> {
     Command::new("git")
-        .args(&["log", "-1", "--date=short", "--pretty=format:%cd"])
+        .args(["log", "-1", "--date=short", "--pretty=format:%cd"])
         .output()
         .ok()
         .and_then(|r| String::from_utf8(r.stdout).ok())

src/bin/main.rs

@@ -445,7 +445,7 @@ fn print_version() {
 fn determine_operation(matches: &Matches) -> Result<Operation, OperationError> {
     if matches.opt_present("h") {
         let topic = matches.opt_str("h");
-        if topic == None {
+        if topic.is_none() {
             return Ok(Operation::Help(HelpOp::None));
         } else if topic == Some("config".to_owned()) {
             return Ok(Operation::Help(HelpOp::Config));

src/format-diff/main.rs

@@ -234,14 +234,14 @@ mod cmd_line_tests {
     #[test]
     fn default_options() {
         let empty: Vec<String> = vec![];
-        let o = Opts::parse_from(&empty);
+        let o = Opts::parse_from(empty);
         assert_eq!(DEFAULT_PATTERN, o.filter);
         assert_eq!(0, o.skip_prefix);
     }
 
     #[test]
     fn good_options() {
-        let o = Opts::parse_from(&["test", "-p", "10", "-f", r".*\.hs"]);
+        let o = Opts::parse_from(["test", "-p", "10", "-f", r".*\.hs"]);
         assert_eq!(r".*\.hs", o.filter);
         assert_eq!(10, o.skip_prefix);
     }
@@ -250,7 +250,7 @@ mod cmd_line_tests {
     fn unexpected_option() {
         assert!(
             Opts::command()
-                .try_get_matches_from(&["test", "unexpected"])
+                .try_get_matches_from(["test", "unexpected"])
                 .is_err()
         );
     }
@@ -259,7 +259,7 @@ mod cmd_line_tests {
     fn unexpected_flag() {
         assert!(
             Opts::command()
-                .try_get_matches_from(&["test", "--flag"])
+                .try_get_matches_from(["test", "--flag"])
                 .is_err()
         );
     }
@@ -268,7 +268,7 @@ mod cmd_line_tests {
     fn overridden_option() {
         assert!(
             Opts::command()
-                .try_get_matches_from(&["test", "-p", "10", "-p", "20"])
+                .try_get_matches_from(["test", "-p", "10", "-p", "20"])
                 .is_err()
         );
     }
@@ -277,7 +277,7 @@ mod cmd_line_tests {
     fn negative_filter() {
         assert!(
             Opts::command()
-                .try_get_matches_from(&["test", "-p", "-1"])
+                .try_get_matches_from(["test", "-p", "-1"])
                 .is_err()
         );
     }