Merge #8063

8063: couple clippy::complexity fixes r=matklad a=matthiaskrgr

avoid redundant `.into()` calls to convert T into identical T (`let x: String = String::from("hello").into();`)
use `if let Some(x)` instead of `.is_some()` + `.unwrap()`
don't clone Copy types
remove redundant wrapped ?s:  `Some(Some(3)?)` can just be `Some(3)`
use `.map(|x| y)` instead of `and_then(|x| Some(y)` on `Option`s

Co-authored-by: Matthias Krüger <[email protected]>

5 files changed, 20 insertions, 23 deletions

diff --git a/crates/mbe/src/benchmark.rs b/crates/mbe/src/benchmark.rs
index 503ad1355..ba814a2e1 100644
--- a/crates/mbe/src/benchmark.rs
+++ b/crates/mbe/src/benchmark.rs
@@ -120,7 +120,7 @@ fn invocation_fixtures(rules: &FxHashMap<String, MacroRules>) -> Vec<(String, tt
                 Some("pat") => parent.token_trees.push(make_ident("foo")),
                 Some("path") => parent.token_trees.push(make_ident("foo")),
                 Some("literal") => parent.token_trees.push(make_literal("1")),
-                Some("expr") => parent.token_trees.push(make_ident("foo").into()),
+                Some("expr") => parent.token_trees.push(make_ident("foo")),
                 Some("lifetime") => {
                     parent.token_trees.push(make_punct('\''));
                     parent.token_trees.push(make_ident("a"));
@@ -157,17 +157,15 @@ fn invocation_fixtures(rules: &FxHashMap<String, MacroRules>) -> Vec<(String, tt
                     if i + 1 != cnt {
                         if let Some(sep) = separator {
                             match sep {
-                                Separator::Literal(it) => parent
-                                    .token_trees
-                                    .push(tt::Leaf::Literal(it.clone().into()).into()),
-                                Separator::Ident(it) => parent
-                                    .token_trees
-                                    .push(tt::Leaf::Ident(it.clone().into()).into()),
+                                Separator::Literal(it) => {
+                                    parent.token_trees.push(tt::Leaf::Literal(it.clone()).into())
+                                }
+                                Separator::Ident(it) => {
+                                    parent.token_trees.push(tt::Leaf::Ident(it.clone()).into())
+                                }
                                 Separator::Puncts(puncts) => {
                                     for it in puncts {
-                                        parent
-                                            .token_trees
-                                            .push(tt::Leaf::Punct(it.clone().into()).into())
+                                        parent.token_trees.push(tt::Leaf::Punct(*it).into())
                                     }
                                 }
                             };
@@ -176,8 +174,7 @@ fn invocation_fixtures(rules: &FxHashMap<String, MacroRules>) -> Vec<(String, tt
                 }
             }
             Op::Subtree { tokens, delimiter } => {
-                let mut subtree =
-                    tt::Subtree { delimiter: delimiter.clone(), token_trees: Vec::new() };
+                let mut subtree = tt::Subtree { delimiter: *delimiter, token_trees: Vec::new() };
                 tokens.iter().for_each(|it| {
                     collect_from_op(it, &mut subtree, seed);
                 });
diff --git a/crates/mbe/src/expander/matcher.rs b/crates/mbe/src/expander/matcher.rs
index 2c69e8968..b6782b4ba 100644
--- a/crates/mbe/src/expander/matcher.rs
+++ b/crates/mbe/src/expander/matcher.rs
@@ -540,7 +540,7 @@ fn match_loop(pattern: &MetaTemplate, src: &tt::Subtree) -> Match {
     let mut src = TtIter::new(src);
     let mut stack: SmallVec<[TtIter; 1]> = SmallVec::new();
     let mut res = Match::default();
-    let mut error_reover_item = None;
+    let mut error_recover_item = None;
 
     let mut bindings_builder = BindingsBuilder::default();
 
@@ -579,9 +579,9 @@ fn match_loop(pattern: &MetaTemplate, src: &tt::Subtree) -> Match {
         stdx::always!(cur_items.is_empty());
 
         if error_items.len() > 0 {
-            error_reover_item = error_items.pop().map(|it| it.bindings);
+            error_recover_item = error_items.pop().map(|it| it.bindings);
         } else if eof_items.len() > 0 {
-            error_reover_item = Some(eof_items[0].bindings.clone());
+            error_recover_item = Some(eof_items[0].bindings.clone());
         }
 
         // We need to do some post processing after the `match_loop_inner`.
@@ -594,8 +594,8 @@ fn match_loop(pattern: &MetaTemplate, src: &tt::Subtree) -> Match {
                 res.bindings = bindings_builder.build(&eof_items[0].bindings);
             } else {
                 // Error recovery
-                if error_reover_item.is_some() {
-                    res.bindings = bindings_builder.build(&error_reover_item.unwrap());
+                if let Some(item) = error_recover_item {
+                    res.bindings = bindings_builder.build(&item);
                 }
                 res.add_err(ExpandError::UnexpectedToken);
             }
@@ -618,7 +618,7 @@ fn match_loop(pattern: &MetaTemplate, src: &tt::Subtree) -> Match {
             }
             res.add_err(err!("leftover tokens"));
 
-            if let Some(error_reover_item) = error_reover_item {
+            if let Some(error_reover_item) = error_recover_item {
                 res.bindings = bindings_builder.build(&error_reover_item);
             }
             return res;
@@ -722,7 +722,7 @@ fn match_meta_var(kind: &str, input: &mut TtIter) -> ExpandResult<Option<Fragmen
                     input
                         .expect_literal()
                         .map(|literal| {
-                            let lit = tt::Leaf::from(literal.clone());
+                            let lit = literal.clone();
                             match neg {
                                 None => Some(lit.into()),
                                 Some(neg) => Some(tt::TokenTree::Subtree(tt::Subtree {
diff --git a/crates/mbe/src/parser.rs b/crates/mbe/src/parser.rs
index 8671322e1..7b5b8ec16 100644
--- a/crates/mbe/src/parser.rs
+++ b/crates/mbe/src/parser.rs
@@ -262,7 +262,7 @@ fn parse_repeat(src: &mut TtIter) -> Result<(Option<Separator>, RepeatKind), Par
                                 if puncts.len() == 3 {
                                     return Err(ParseError::InvalidRepeat);
                                 }
-                                puncts.push(punct.clone())
+                                puncts.push(*punct)
                             }
                             _ => return Err(ParseError::InvalidRepeat),
                         }
diff --git a/crates/mbe/src/syntax_bridge.rs b/crates/mbe/src/syntax_bridge.rs
index b715ebfc4..85163c4b3 100644
--- a/crates/mbe/src/syntax_bridge.rs
+++ b/crates/mbe/src/syntax_bridge.rs
@@ -130,7 +130,7 @@ pub fn parse_exprs_with_sep(tt: &tt::Subtree, sep: char) -> Vec<tt::Subtree> {
         res.push(match expanded.value {
             None => break,
             Some(tt @ tt::TokenTree::Leaf(_)) => {
-                tt::Subtree { delimiter: None, token_trees: vec![tt.into()] }
+                tt::Subtree { delimiter: None, token_trees: vec![tt] }
             }
             Some(tt::TokenTree::Subtree(tt)) => tt,
         });
@@ -727,7 +727,7 @@ impl<'a> TreeSink for TtTreeSink<'a> {
             // Note: We always assume the semi-colon would be the last token in
             // other parts of RA such that we don't add whitespace here.
             if curr.spacing == tt::Spacing::Alone && curr.char != ';' {
-                self.inner.token(WHITESPACE, " ".into());
+                self.inner.token(WHITESPACE, " ");
                 self.text_pos += TextSize::of(' ');
             }
         }
diff --git a/crates/mbe/src/tests.rs b/crates/mbe/src/tests.rs
index eca0bcc18..25c374b9b 100644
--- a/crates/mbe/src/tests.rs
+++ b/crates/mbe/src/tests.rs
@@ -35,7 +35,7 @@ mod rule_parsing {
     fn test_invalid_arms() {
         fn check(macro_body: &str, err: ParseError) {
             let m = parse_macro_arm(macro_body);
-            assert_eq!(m, Err(err.into()));
+            assert_eq!(m, Err(err));
         }
         check("invalid", ParseError::Expected("expected subtree".into()));