Allow match_single_binding lint in clippy_lints basecode

clippy_lints/src/eval_order_dependence.rs

@@ -100,6 +100,7 @@ struct DivergenceVisitor<'a, 'tcx> {
 }
 
 impl<'a, 'tcx> DivergenceVisitor<'a, 'tcx> {
+    #[allow(clippy::match_single_binding)]
     fn maybe_walk_expr(&mut self, e: &'tcx Expr<'_>) {
         match e.kind {
             ExprKind::Closure(..) => {},

clippy_lints/src/matches.rs

@@ -989,6 +989,7 @@ where
     }
 
     impl<'a, T: Copy> Kind<'a, T> {
+        #[allow(clippy::match_single_binding)]
         fn range(&self) -> &'a SpannedRange<T> {
             match *self {
                 Kind::Start(_, r) | Kind::End(_, r) => r,

clippy_lints/src/shadow.rs

@@ -309,6 +309,7 @@ fn lint_shadow<'a, 'tcx>(
     }
 }
 
+#[allow(clippy::match_single_binding)]
 fn check_expr<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>, bindings: &mut Vec<(Name, Span)>) {
     if in_external_macro(cx.sess(), expr.span) {
         return;

clippy_lints/src/slow_vector_initialization.rs

@@ -145,6 +145,7 @@ impl SlowVectorInit {
         }
     }
 
+    #[allow(clippy::match_single_binding)]
     fn lint_initialization<'tcx>(
         cx: &LateContext<'_, 'tcx>,
         initialization: &InitializationType<'tcx>,

clippy_lints/src/types.rs

@@ -2254,12 +2254,14 @@ impl<'tcx> ImplicitHasherType<'tcx> {
         }
     }
 
+    #[allow(clippy::match_single_binding)]
     fn ty(&self) -> Ty<'tcx> {
         match *self {
             ImplicitHasherType::HashMap(_, ty, ..) | ImplicitHasherType::HashSet(_, ty, ..) => ty,
         }
     }
 
+    #[allow(clippy::match_single_binding)]
     fn span(&self) -> Span {
         match *self {
             ImplicitHasherType::HashMap(span, ..) | ImplicitHasherType::HashSet(span, ..) => span,

clippy_lints/src/utils/author.rs

@@ -191,7 +191,7 @@ struct PrintVisitor {
 impl<'tcx> Visitor<'tcx> for PrintVisitor {
     type Map = Map<'tcx>;
 
-    #[allow(clippy::too_many_lines)]
+    #[allow(clippy::too_many_lines, clippy::match_single_binding)]
     fn visit_expr(&mut self, expr: &Expr<'_>) {
         // handle if desugarings
         // TODO add more desugarings here

clippy_lints/src/utils/hir_utils.rs

@@ -161,6 +161,7 @@ impl<'a, 'tcx> SpanlessEq<'a, 'tcx> {
         left.ident.name == right.ident.name && self.eq_expr(&left.expr, &right.expr)
     }
 
+    #[allow(clippy::match_single_binding)]
     fn eq_guard(&mut self, left: &Guard<'_>, right: &Guard<'_>) -> bool {
         match (left, right) {
             (Guard::If(l), Guard::If(r)) => self.eq_expr(l, r),
@@ -579,6 +580,7 @@ impl<'a, 'tcx> SpanlessHash<'a, 'tcx> {
         }
     }
 
+    #[allow(clippy::match_single_binding)]
     pub fn hash_guard(&mut self, g: &Guard<'_>) {
         match g {
             Guard::If(ref expr) => {

clippy_lints/src/utils/inspector.rs

@@ -514,6 +514,7 @@ fn print_pat(cx: &LateContext<'_, '_>, pat: &hir::Pat<'_>, indent: usize) {
     }
 }
 
+#[allow(clippy::match_single_binding)]
 fn print_guard(cx: &LateContext<'_, '_>, guard: &hir::Guard<'_>, indent: usize) {
     let ind = "  ".repeat(indent);
     println!("{}+", ind);

clippy_lints/src/utils/sugg.rs

@@ -33,6 +33,7 @@ pub enum Sugg<'a> {
 pub const ONE: Sugg<'static> = Sugg::NonParen(Cow::Borrowed("1"));
 
 impl Display for Sugg<'_> {
+    #[allow(clippy::match_single_binding)]
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
         match *self {
             Sugg::NonParen(ref s) | Sugg::MaybeParen(ref s) | Sugg::BinOp(_, ref s) => s.fmt(f),