modify code

[rust.git] / clippy_lints / src / matches.rs

diff --git a/clippy_lints/src/matches.rs b/clippy_lints/src/matches.rs
index 33d022c73a5e7c007aa286918e8a78e6db392321..2579404fb18cc5b152fd8448903475d4e1ba5bbf 100644 (file)
--- a/clippy_lints/src/matches.rs
+++ b/clippy_lints/src/matches.rs
@@ -25,12 +25,12 @@
     Mutability, Node, Pat, PatKind, PathSegment, QPath, RangeEnd, TyKind,
 };
 use rustc_hir::{HirIdMap, HirIdSet};
-use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty::{self, Ty, TyS, VariantDef};
 use rustc_semver::RustcVersion;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::source_map::{Span, Spanned};
-use rustc_span::sym;
+use rustc_span::{sym, symbol::kw};
 use std::cmp::Ordering;
 use std::collections::hash_map::Entry;
 
@@ -961,13 +961,13 @@ fn check_wild_err_arm<'tcx>(cx: &LateContext<'tcx>, ex: &Expr<'tcx>, arms: &[Arm
                 let path_str = rustc_hir_pretty::to_string(rustc_hir_pretty::NO_ANN, |s| s.print_qpath(path, false));
                 if path_str == "Err" {
                     let mut matching_wild = inner.iter().any(is_wild);
-                    let mut ident_bind_name = String::from("_");
+                    let mut ident_bind_name = kw::Underscore;
                     if !matching_wild {
                         // Looking for unused bindings (i.e.: `_e`)
                         for pat in inner.iter() {
                             if let PatKind::Binding(_, id, ident, None) = pat.kind {
                                 if ident.as_str().starts_with('_') && !is_local_used(cx, arm.body, id) {
-                                    ident_bind_name = ident.name.as_str().to_string();
+                                    ident_bind_name = ident.name;
                                     matching_wild = true;
                                 }
                             }
@@ -982,7 +982,7 @@ fn check_wild_err_arm<'tcx>(cx: &LateContext<'tcx>, ex: &Expr<'tcx>, arms: &[Arm
                             span_lint_and_note(cx,
                                 MATCH_WILD_ERR_ARM,
                                 arm.pat.span,
-                                &format!("`Err({})` matches all errors", &ident_bind_name),
+                                &format!("`Err({})` matches all errors", ident_bind_name),
                                 None,
                                 "match each error separately or use the error output, or use `.except(msg)` if the error case is unreachable",
                             );
@@ -1909,7 +1909,7 @@ fn visit_expr(&mut self, expr: &'tcx Expr<'tcx>) {
                     },
                     // Method calls can take self by reference.
                     // e.g. In `String::new().len()` the string is a temporary value.
-                    ExprKind::MethodCall(_, _, [self_arg, args @ ..], _) => {
+                    ExprKind::MethodCall(_, [self_arg, args @ ..], _) => {
                         if !matches!(self_arg.kind, ExprKind::Path(_)) {
                             let self_by_ref = self
                                 .cx
@@ -2020,7 +2020,7 @@ fn find_sugg_for_if_let<'tcx>(
         // check that `while_let_on_iterator` lint does not trigger
         if_chain! {
             if keyword == "while";
-            if let ExprKind::MethodCall(method_path, _, _, _) = let_expr.kind;
+            if let ExprKind::MethodCall(method_path, _, _) = let_expr.kind;
             if method_path.ident.name == sym::next;
             if is_trait_method(cx, let_expr, sym::Iterator);
             then {