6 files changed, 17 insertions, 25 deletions

diff --git a/crates/mbe/src/benchmark.rs b/crates/mbe/src/benchmark.rs
index 38707ffa5..18eb97f0d 100644
--- a/crates/mbe/src/benchmark.rs
+++ b/crates/mbe/src/benchmark.rs
@@ -187,7 +187,7 @@ fn invocation_fixtures(rules: &FxHashMap<String, MacroRules>) -> Vec<(String, tt
             let a = 1664525;
             let c = 1013904223;
             *seed = usize::wrapping_add(usize::wrapping_mul(*seed, a), c);
-            return *seed;
+            *seed
         }
         fn make_ident(ident: &str) -> tt::TokenTree {
             tt::Leaf::Ident(tt::Ident { id: tt::TokenId::unspecified(), text: SmolStr::new(ident) })
diff --git a/crates/mbe/src/expander/matcher.rs b/crates/mbe/src/expander/matcher.rs
index 84ca3ff87..c982eb58f 100644
--- a/crates/mbe/src/expander/matcher.rs
+++ b/crates/mbe/src/expander/matcher.rs
@@ -219,7 +219,7 @@ impl BindingsBuilder {
         bindings
     }
 
-    fn build_inner(&self, bindings: &mut Bindings, link_nodes: &Vec<LinkNode<Rc<BindingKind>>>) {
+    fn build_inner(&self, bindings: &mut Bindings, link_nodes: &[LinkNode<Rc<BindingKind>>]) {
         let mut nodes = Vec::new();
         self.collect_nodes(&link_nodes, &mut nodes);
 
@@ -301,7 +301,7 @@ impl BindingsBuilder {
 
     fn collect_nodes<'a>(
         &'a self,
-        link_nodes: &'a Vec<LinkNode<Rc<BindingKind>>>,
+        link_nodes: &'a [LinkNode<Rc<BindingKind>>],
         nodes: &mut Vec<&'a Rc<BindingKind>>,
     ) {
         link_nodes.iter().for_each(|it| match it {
@@ -494,15 +494,8 @@ fn match_loop_inner<'t>(
                         }
                         Some(err) => {
                             res.add_err(err);
-                            match match_res.value {
-                                Some(fragment) => {
-                                    bindings_builder.push_fragment(
-                                        &mut item.bindings,
-                                        &name,
-                                        fragment,
-                                    );
-                                }
-                                _ => {}
+                            if let Some(fragment) = match_res.value {
+                                bindings_builder.push_fragment(&mut item.bindings, &name, fragment);
                             }
                             item.is_error = true;
                             error_items.push(item);
@@ -578,9 +571,9 @@ fn match_loop(pattern: &MetaTemplate, src: &tt::Subtree) -> Match {
         );
         stdx::always!(cur_items.is_empty());
 
-        if error_items.len() > 0 {
+        if !error_items.is_empty() {
             error_recover_item = error_items.pop().map(|it| it.bindings);
-        } else if eof_items.len() > 0 {
+        } else if !eof_items.is_empty() {
             error_recover_item = Some(eof_items[0].bindings.clone());
         }
 
@@ -793,7 +786,7 @@ impl<'a> TtIter<'a> {
             _ => (),
         }
 
-        let tt = self.next().ok_or_else(|| ())?.clone();
+        let tt = self.next().ok_or(())?.clone();
         let punct = match tt {
             tt::TokenTree::Leaf(tt::Leaf::Punct(punct)) if punct.spacing == tt::Spacing::Joint => {
                 punct
diff --git a/crates/mbe/src/lib.rs b/crates/mbe/src/lib.rs
index b95374b76..380a50744 100644
--- a/crates/mbe/src/lib.rs
+++ b/crates/mbe/src/lib.rs
@@ -295,8 +295,8 @@ fn validate(pattern: &MetaTemplate) -> Result<(), ParseError> {
                 // Checks that no repetition which could match an empty token
                 // https://github.com/rust-lang/rust/blob/a58b1ed44f5e06976de2bdc4d7dc81c36a96934f/src/librustc_expand/mbe/macro_rules.rs#L558
 
-                if separator.is_none() {
-                    if subtree.iter().all(|child_op| {
+                if separator.is_none()
+                    && subtree.iter().all(|child_op| {
                         match child_op {
                             Op::Var { kind, .. } => {
                                 // vis is optional
@@ -314,9 +314,9 @@ fn validate(pattern: &MetaTemplate) -> Result<(), ParseError> {
                             Op::Subtree { .. } => {}
                         }
                         false
-                    }) {
-                        return Err(ParseError::RepetitionEmptyTokenTree);
-                    }
+                    })
+                {
+                    return Err(ParseError::RepetitionEmptyTokenTree);
                 }
                 validate(subtree)?
             }
diff --git a/crates/mbe/src/parser.rs b/crates/mbe/src/parser.rs
index 61b2a4955..04c0d3e75 100644
--- a/crates/mbe/src/parser.rs
+++ b/crates/mbe/src/parser.rs
@@ -213,7 +213,7 @@ fn next_op<'a>(first: &tt::TokenTree, src: &mut TtIter<'a>, mode: Mode) -> Resul
     Ok(res)
 }
 
-fn eat_fragment_kind<'a>(src: &mut TtIter<'a>, mode: Mode) -> Result<Option<SmolStr>, ParseError> {
+fn eat_fragment_kind(src: &mut TtIter<'_>, mode: Mode) -> Result<Option<SmolStr>, ParseError> {
     if let Mode::Pattern = mode {
         src.expect_char(':').map_err(|()| err!("bad fragment specifier 1"))?;
         let ident = src.expect_ident().map_err(|()| err!("bad fragment specifier 1"))?;
diff --git a/crates/mbe/src/syntax_bridge.rs b/crates/mbe/src/syntax_bridge.rs
index b11172caf..978c75747 100644
--- a/crates/mbe/src/syntax_bridge.rs
+++ b/crates/mbe/src/syntax_bridge.rs
@@ -243,8 +243,7 @@ trait TokenConvertor {
     type Token: SrcToken;
 
     fn go(&mut self) -> tt::Subtree {
-        let mut subtree = tt::Subtree::default();
-        subtree.delimiter = None;
+        let mut subtree = tt::Subtree { delimiter: None, ..Default::default() };
         while self.peek().is_some() {
             self.collect_leaf(&mut subtree.token_trees);
         }
@@ -506,7 +505,7 @@ impl TokenConvertor for Convertor {
 
     fn peek(&self) -> Option<Self::Token> {
         if let Some((punct, mut offset)) = self.punct_offset.clone() {
-            offset = offset + TextSize::of('.');
+            offset += TextSize::of('.');
             if usize::from(offset) < punct.text().len() {
                 return Some(SynToken::Punch(punct, offset));
             }
diff --git a/crates/mbe/src/tt_iter.rs b/crates/mbe/src/tt_iter.rs
index 99a8d250b..bd54f2442 100644
--- a/crates/mbe/src/tt_iter.rs
+++ b/crates/mbe/src/tt_iter.rs
@@ -138,7 +138,7 @@ impl<'a> TtIter<'a> {
             }
         }
         self.inner = self.inner.as_slice()[res.len()..].iter();
-        if res.len() == 0 && err.is_none() {
+        if res.is_empty() && err.is_none() {
             err = Some(err!("no tokens consumed"));
         }
         let res = match res.len() {