From 5df1f6681dca1a2028a4e6b60d3ab789c00b4cf8 Mon Sep 17 00:00:00 2001
From: Nilstrieb <48135649+Nilstrieb@users.noreply.github.com>
Date: Fri, 7 Jul 2023 20:28:51 +0200
Subject: [PATCH] Pass correct substs to `implements_trait` in
 `incorrect_impls`

`Copy<T>` does in fact not exist. The substs on the trait_ref contain
the `Self` type of the impl as the first parameter, so passing that
to `implements_trait`, which then nicely prepends the `Self` type
for us does not end will.
---
 clippy_lints/src/incorrect_impls.rs | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/clippy_lints/src/incorrect_impls.rs b/clippy_lints/src/incorrect_impls.rs
index 13cc0b23ba33..ed21df4ff884 100644
--- a/clippy_lints/src/incorrect_impls.rs
+++ b/clippy_lints/src/incorrect_impls.rs
@@ -1,7 +1,6 @@
 use clippy_utils::{diagnostics::span_lint_and_sugg, get_parent_node, last_path_segment, ty::implements_trait};
 use rustc_errors::Applicability;
-use rustc_hir::{ExprKind, ImplItem, ImplItemKind, ItemKind, Node, UnOp};
-use rustc_hir_analysis::hir_ty_to_ty;
+use rustc_hir::{ExprKind, ImplItem, ImplItemKind, Node, UnOp};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_middle::ty::EarlyBinder;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
@@ -55,9 +54,6 @@ impl LateLintPass<'_> for IncorrectImpls {
         let Some(Node::Item(item)) = node else {
             return;
         };
-        let ItemKind::Impl(imp) = item.kind else {
-            return;
-        };
         let Some(trait_impl) = cx.tcx.impl_trait_ref(item.owner_id).map(EarlyBinder::skip_binder) else {
             return;
         };
@@ -80,9 +76,9 @@ impl LateLintPass<'_> for IncorrectImpls {
             && let Some(copy_def_id) = cx.tcx.get_diagnostic_item(sym::Copy)
             && implements_trait(
                     cx,
-                    hir_ty_to_ty(cx.tcx, imp.self_ty),
+                    trait_impl.self_ty(),
                     copy_def_id,
-                    trait_impl.substs,
+                    &[],
                 )
         {
             if impl_item.ident.name == sym::clone {