Auto merge of #7138 - mgacek8:issue6808_iter_cloned_collect_FN_with_large_array,...

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

diff --git a/clippy_lints/src/mem_replace.rs b/clippy_lints/src/mem_replace.rs
index 0418c616efa8ad39344c7e1832e9705c80d40cfb..183daee36177489843452fb7ce3350a2a6c742ff 100644 (file)
--- a/clippy_lints/src/mem_replace.rs
+++ b/clippy_lints/src/mem_replace.rs
@@ -1,10 +1,10 @@
 use clippy_utils::diagnostics::{span_lint_and_help, span_lint_and_sugg, span_lint_and_then};
-use clippy_utils::is_diagnostic_assoc_item;
 use clippy_utils::source::{snippet, snippet_with_applicability};
-use clippy_utils::{in_macro, match_def_path, match_qpath, meets_msrv, paths};
+use clippy_utils::{in_macro, is_diag_trait_item, is_lang_ctor, match_def_path, meets_msrv, msrvs, paths};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir::def_id::DefId;
+use rustc_hir::LangItem::OptionNone;
 use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, QPath};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
@@ -102,21 +102,21 @@
 fn check_replace_option_with_none(cx: &LateContext<'_>, src: &Expr<'_>, dest: &Expr<'_>, expr_span: Span) {
     if let ExprKind::Path(ref replacement_qpath) = src.kind {
         // Check that second argument is `Option::None`
-        if match_qpath(replacement_qpath, &paths::OPTION_NONE) {
+        if is_lang_ctor(cx, replacement_qpath, OptionNone) {
             // Since this is a late pass (already type-checked),
             // and we already know that the second argument is an
             // `Option`, we do not need to check the first
             // argument's type. All that's left is to get
             // replacee's path.
             let replaced_path = match dest.kind {
-                ExprKind::AddrOf(BorrowKind::Ref, Mutability::Mut, ref replaced) => {
-                    if let ExprKind::Path(QPath::Resolved(None, ref replaced_path)) = replaced.kind {
+                ExprKind::AddrOf(BorrowKind::Ref, Mutability::Mut, replaced) => {
+                    if let ExprKind::Path(QPath::Resolved(None, replaced_path)) = replaced.kind {
                         replaced_path
                     } else {
                         return;
                     }
                 },
-                ExprKind::Path(QPath::Resolved(None, ref replaced_path)) => replaced_path,
+                ExprKind::Path(QPath::Resolved(None, replaced_path)) => replaced_path,
                 _ => return,
             };
 
@@ -161,7 +161,7 @@ fn check_replace_with_uninit(cx: &LateContext<'_>, src: &Expr<'_>, dest: &Expr<'
     }
 
     if_chain! {
-        if let ExprKind::Call(ref repl_func, ref repl_args) = src.kind;
+        if let ExprKind::Call(repl_func, repl_args) = src.kind;
         if repl_args.is_empty();
         if let ExprKind::Path(ref repl_func_qpath) = repl_func.kind;
         if let Some(repl_def_id) = cx.qpath_res(repl_func_qpath, repl_func.hir_id).opt_def_id();
@@ -210,27 +210,27 @@ fn is_default_equivalent_ctor(cx: &LateContext<'_>, def_id: DefId, path: &QPath<
         sym::BinaryHeap,
     ];
 
-    if std_types_symbols
-        .iter()
-        .any(|symbol| is_diagnostic_assoc_item(cx, def_id, *symbol))
-    {
-        if let QPath::TypeRelative(_, ref method) = path {
-            if method.ident.name == sym::new {
-                return true;
+    if let QPath::TypeRelative(_, method) = path {
+        if method.ident.name == sym::new {
+            if let Some(impl_did) = cx.tcx.impl_of_method(def_id) {
+                if let Some(adt) = cx.tcx.type_of(impl_did).ty_adt_def() {
+                    return std_types_symbols
+                        .iter()
+                        .any(|&symbol| cx.tcx.is_diagnostic_item(symbol, adt.did));
+                }
             }
         }
     }
-
     false
 }
 
 fn check_replace_with_default(cx: &LateContext<'_>, src: &Expr<'_>, dest: &Expr<'_>, expr_span: Span) {
     if_chain! {
-        if let ExprKind::Call(ref repl_func, _) = src.kind;
+        if let ExprKind::Call(repl_func, _) = src.kind;
         if !in_external_macro(cx.tcx.sess, expr_span);
         if let ExprKind::Path(ref repl_func_qpath) = repl_func.kind;
         if let Some(repl_def_id) = cx.qpath_res(repl_func_qpath, repl_func.hir_id).opt_def_id();
-        if is_diagnostic_assoc_item(cx, repl_def_id, sym::Default)
+        if is_diag_trait_item(cx, repl_def_id, sym::Default)
             || is_default_equivalent_ctor(cx, repl_def_id, repl_func_qpath);
 
         then {
@@ -256,8 +256,6 @@ fn check_replace_with_default(cx: &LateContext<'_>, src: &Expr<'_>, dest: &Expr<
     }
 }
 
-const MEM_REPLACE_WITH_DEFAULT_MSRV: RustcVersion = RustcVersion::new(1, 40, 0);
-
 pub struct MemReplace {
     msrv: Option<RustcVersion>,
 }
@@ -273,15 +271,15 @@ impl<'tcx> LateLintPass<'tcx> for MemReplace {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if_chain! {
             // Check that `expr` is a call to `mem::replace()`
-            if let ExprKind::Call(ref func, ref func_args) = expr.kind;
+            if let ExprKind::Call(func, func_args) = expr.kind;
             if let ExprKind::Path(ref func_qpath) = func.kind;
             if let Some(def_id) = cx.qpath_res(func_qpath, func.hir_id).opt_def_id();
             if match_def_path(cx, def_id, &paths::MEM_REPLACE);
-            if let [dest, src] = &**func_args;
+            if let [dest, src] = func_args;
             then {
                 check_replace_option_with_none(cx, src, dest, expr.span);
                 check_replace_with_uninit(cx, src, dest, expr.span);
-                if meets_msrv(self.msrv.as_ref(), &MEM_REPLACE_WITH_DEFAULT_MSRV) {
+                if meets_msrv(self.msrv.as_ref(), &msrvs::MEM_TAKE) {
                     check_replace_with_default(cx, src, dest, expr.span);
                 }
             }