Auto merge of #87140 - camsteffen:pat-slice-refs, r=oli-obk

Remove refs from Pat slices

Changes `PatKind::Or(&'hir [&'hir Pat<'hir>])` to `PatKind::Or(&'hir [Pat<'hir>])` and others. This is more consistent with `ExprKind`, saves a little memory, and is a little easier to use.

6 files changed, 20 insertions, 25 deletions

diff --git a/src/librustdoc/clean/utils.rs b/src/librustdoc/clean/utils.rs
index 7ae602c8033..dea016a467d 100644
--- a/src/librustdoc/clean/utils.rs
+++ b/src/librustdoc/clean/utils.rs
@@ -260,17 +260,12 @@ crate fn name_from_pat(p: &hir::Pat<'_>) -> Symbol {
         PatKind::Wild | PatKind::Struct(..) => return kw::Underscore,
         PatKind::Binding(_, _, ident, _) => return ident.name,
         PatKind::TupleStruct(ref p, ..) | PatKind::Path(ref p) => qpath_to_string(p),
-        PatKind::Or(ref pats) => pats
-            .iter()
-            .map(|p| name_from_pat(&**p).to_string())
-            .collect::<Vec<String>>()
-            .join(" | "),
+        PatKind::Or(ref pats) => {
+            pats.iter().map(|p| name_from_pat(p).to_string()).collect::<Vec<String>>().join(" | ")
+        }
         PatKind::Tuple(ref elts, _) => format!(
             "({})",
-            elts.iter()
-                .map(|p| name_from_pat(&**p).to_string())
-                .collect::<Vec<String>>()
-                .join(", ")
+            elts.iter().map(|p| name_from_pat(p).to_string()).collect::<Vec<String>>().join(", ")
         ),
         PatKind::Box(ref p) => return name_from_pat(&**p),
         PatKind::Ref(ref p, _) => return name_from_pat(&**p),
@@ -282,9 +277,9 @@ crate fn name_from_pat(p: &hir::Pat<'_>) -> Symbol {
         }
         PatKind::Range(..) => return kw::Underscore,
         PatKind::Slice(ref begin, ref mid, ref end) => {
-            let begin = begin.iter().map(|p| name_from_pat(&**p).to_string());
+            let begin = begin.iter().map(|p| name_from_pat(p).to_string());
             let mid = mid.as_ref().map(|p| format!("..{}", name_from_pat(&**p))).into_iter();
-            let end = end.iter().map(|p| name_from_pat(&**p).to_string());
+            let end = end.iter().map(|p| name_from_pat(p).to_string());
             format!("[{}]", begin.chain(mid).chain(end).collect::<Vec<_>>().join(", "))
         }
     })
diff --git a/src/tools/clippy/clippy_lints/src/manual_unwrap_or.rs b/src/tools/clippy/clippy_lints/src/manual_unwrap_or.rs
index 18038dd7819..9d8d77cf8f0 100644
--- a/src/tools/clippy/clippy_lints/src/manual_unwrap_or.rs
+++ b/src/tools/clippy/clippy_lints/src/manual_unwrap_or.rs
@@ -61,13 +61,13 @@ fn lint_manual_unwrap_or<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
             if let Some((idx, or_arm)) = arms.iter().enumerate().find(|(_, arm)| {
                 match arm.pat.kind {
                     PatKind::Path(ref qpath) => is_lang_ctor(cx, qpath, OptionNone),
-                    PatKind::TupleStruct(ref qpath, &[pat], _) =>
+                    PatKind::TupleStruct(ref qpath, [pat], _) =>
                         matches!(pat.kind, PatKind::Wild) && is_lang_ctor(cx, qpath, ResultErr),
                     _ => false,
                 }
             });
             let unwrap_arm = &arms[1 - idx];
-            if let PatKind::TupleStruct(ref qpath, &[unwrap_pat], _) = unwrap_arm.pat.kind;
+            if let PatKind::TupleStruct(ref qpath, [unwrap_pat], _) = unwrap_arm.pat.kind;
             if is_lang_ctor(cx, qpath, OptionSome) || is_lang_ctor(cx, qpath, ResultOk);
             if let PatKind::Binding(_, binding_hir_id, ..) = unwrap_pat.kind;
             if path_to_local_id(unwrap_arm.body, binding_hir_id);
diff --git a/src/tools/clippy/clippy_lints/src/matches.rs b/src/tools/clippy/clippy_lints/src/matches.rs
index 986469a2b69..6d5ce3373f7 100644
--- a/src/tools/clippy/clippy_lints/src/matches.rs
+++ b/src/tools/clippy/clippy_lints/src/matches.rs
@@ -625,7 +625,7 @@ impl<'tcx> LateLintPass<'tcx> for Matches {
             if let PatKind::TupleStruct(
                 QPath::Resolved(None, variant_name), args, _) = arms[0].pat.kind;
             if args.len() == 1;
-            if let PatKind::Binding(_, arg, ..) = strip_pat_refs(args[0]).kind;
+            if let PatKind::Binding(_, arg, ..) = strip_pat_refs(&args[0]).kind;
             let body = remove_blocks(arms[0].body);
             if path_to_local_id(body, arg);
 
diff --git a/src/tools/clippy/clippy_lints/src/option_if_let_else.rs b/src/tools/clippy/clippy_lints/src/option_if_let_else.rs
index b6af4175edf..b2be35bdddb 100644
--- a/src/tools/clippy/clippy_lints/src/option_if_let_else.rs
+++ b/src/tools/clippy/clippy_lints/src/option_if_let_else.rs
@@ -132,7 +132,7 @@ fn detect_option_if_let_else<'tcx>(
         if !is_else_clause(cx.tcx, expr);
         if arms.len() == 2;
         if !is_result_ok(cx, cond_expr); // Don't lint on Result::ok because a different lint does it already
-        if let PatKind::TupleStruct(struct_qpath, &[inner_pat], _) = &arms[0].pat.kind;
+        if let PatKind::TupleStruct(struct_qpath, [inner_pat], _) = &arms[0].pat.kind;
         if is_lang_ctor(cx, struct_qpath, OptionSome);
         if let PatKind::Binding(bind_annotation, _, id, _) = &inner_pat.kind;
         if !contains_return_break_continue_macro(arms[0].body);
diff --git a/src/tools/clippy/clippy_lints/src/pattern_type_mismatch.rs b/src/tools/clippy/clippy_lints/src/pattern_type_mismatch.rs
index 9bab783998a..ea4065d371b 100644
--- a/src/tools/clippy/clippy_lints/src/pattern_type_mismatch.rs
+++ b/src/tools/clippy/clippy_lints/src/pattern_type_mismatch.rs
@@ -258,7 +258,7 @@ fn get_variant<'a>(adt_def: &'a AdtDef, qpath: &QPath<'_>) -> Option<&'a Variant
 
 fn find_first_mismatch_in_tuple<'tcx, I>(
     cx: &LateContext<'tcx>,
-    pats: &[&Pat<'_>],
+    pats: &[Pat<'_>],
     ty_iter_src: I,
 ) -> Option<(Span, Mutability, Level)>
 where
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
index 6db221ab0fd..4f0a9f442ed 100644
--- a/src/tools/clippy/clippy_utils/src/lib.rs
+++ b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -255,7 +255,7 @@ pub fn in_macro(span: Span) -> bool {
 }
 
 /// Checks if given pattern is a wildcard (`_`)
-pub fn is_wild<'tcx>(pat: &impl std::ops::Deref<Target = Pat<'tcx>>) -> bool {
+pub fn is_wild(pat: &Pat<'_>) -> bool {
     matches!(pat.kind, PatKind::Wild)
 }
 
@@ -1023,8 +1023,8 @@ pub fn is_refutable(cx: &LateContext<'_>, pat: &Pat<'_>) -> bool {
         )
     }
 
-    fn are_refutable<'a, I: Iterator<Item = &'a Pat<'a>>>(cx: &LateContext<'_>, mut i: I) -> bool {
-        i.any(|pat| is_refutable(cx, pat))
+    fn are_refutable<'a, I: IntoIterator<Item = &'a Pat<'a>>>(cx: &LateContext<'_>, i: I) -> bool {
+        i.into_iter().any(|pat| is_refutable(cx, pat))
     }
 
     match pat.kind {
@@ -1035,23 +1035,23 @@ pub fn is_refutable(cx: &LateContext<'_>, pat: &Pat<'_>) -> bool {
         PatKind::Path(ref qpath) => is_enum_variant(cx, qpath, pat.hir_id),
         PatKind::Or(pats) => {
             // TODO: should be the honest check, that pats is exhaustive set
-            are_refutable(cx, pats.iter().map(|pat| &**pat))
+            are_refutable(cx, pats)
         },
-        PatKind::Tuple(pats, _) => are_refutable(cx, pats.iter().map(|pat| &**pat)),
+        PatKind::Tuple(pats, _) => are_refutable(cx, pats),
         PatKind::Struct(ref qpath, fields, _) => {
             is_enum_variant(cx, qpath, pat.hir_id) || are_refutable(cx, fields.iter().map(|field| &*field.pat))
         },
         PatKind::TupleStruct(ref qpath, pats, _) => {
-            is_enum_variant(cx, qpath, pat.hir_id) || are_refutable(cx, pats.iter().map(|pat| &**pat))
+            is_enum_variant(cx, qpath, pat.hir_id) || are_refutable(cx, pats)
         },
-        PatKind::Slice(head, ref middle, tail) => {
+        PatKind::Slice(head, middle, tail) => {
             match &cx.typeck_results().node_type(pat.hir_id).kind() {
                 rustc_ty::Slice(..) => {
                     // [..] is the only irrefutable slice pattern.
                     !head.is_empty() || middle.is_none() || !tail.is_empty()
                 },
                 rustc_ty::Array(..) => {
-                    are_refutable(cx, head.iter().chain(middle).chain(tail.iter()).map(|pat| &**pat))
+                    are_refutable(cx, head.iter().chain(middle).chain(tail.iter()))
                 },
                 _ => {
                     // unreachable!()
@@ -1066,7 +1066,7 @@ pub fn is_refutable(cx: &LateContext<'_>, pat: &Pat<'_>) -> bool {
 /// the function once on the given pattern.
 pub fn recurse_or_patterns<'tcx, F: FnMut(&'tcx Pat<'tcx>)>(pat: &'tcx Pat<'tcx>, mut f: F) {
     if let PatKind::Or(pats) = pat.kind {
-        pats.iter().copied().for_each(f);
+        pats.iter().for_each(f);
     } else {
         f(pat);
     }