Fix latest clippy warnings (#3049)

crates/nu-parser/src/lex/token_group.rs

@@ -10,12 +10,12 @@ pub struct TokenBuilder<T: HasSpan> {
     contents: Option<Vec<T>>,
 }
 
-impl<T> Into<Vec<T>> for TokenBuilder<T>
+impl<T> From<TokenBuilder<T>> for Vec<T>
 where
     T: HasSpan,
 {
-    fn into(self) -> Vec<T> {
-        self.contents.unwrap_or_else(Vec::new)
+    fn from(x: TokenBuilder<T>) -> Self {
+        x.contents.unwrap_or_else(Vec::new)
     }
 }
 

crates/nu-parser/src/parse.rs

@@ -2140,7 +2140,7 @@ pub fn parse(
 }
 
 #[test]
-fn unit_parse_byte_units() -> Result<(), ParseError> {
+fn unit_parse_byte_units() {
     struct TestCase {
         string: String,
         value: i64,
@@ -2275,5 +2275,4 @@ fn unit_parse_byte_units() -> Result<(), ParseError> {
             )
         );
     }
-    Ok(())
 }

crates/nu-parser/src/parse/def/primitives.rs

@@ -187,7 +187,7 @@ pub fn parse_type_token(type_: &Token) -> (SyntaxShape, Option<ParseError>) {
 pub(crate) fn parse_rest_name(name_token: &Token) -> Option<ParseError> {
     return if let TokenContents::Baseline(name) = &name_token.contents {
         if !name.starts_with("...") {
-            parse_rest_name_err(name_token)
+            Some(parse_rest_name_err(name_token))
         } else if !name.starts_with("...rest") {
             Some(ParseError::mismatch(
                 "rest argument name to be 'rest'",
@@ -197,13 +197,10 @@ pub(crate) fn parse_rest_name(name_token: &Token) -> Option<ParseError> {
             None
         }
     } else {
-        parse_rest_name_err(name_token)
+        Some(parse_rest_name_err(name_token))
     };
 
-    fn parse_rest_name_err(token: &Token) -> Option<ParseError> {
-        Some(ParseError::mismatch(
-            "...rest",
-            token_to_spanned_string(token),
-        ))
+    fn parse_rest_name_err(token: &Token) -> ParseError {
+        ParseError::mismatch("...rest", token_to_spanned_string(token))
     }
 }