Rollup merge of #83092 - petrochenkov:qspan, r=estebank

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

diff --git a/clippy_lints/src/inherent_to_string.rs b/clippy_lints/src/inherent_to_string.rs
index 24c0b1cb80e66f1950c0ea5348ad5bf4989cecf2..c1f3e1d9d685c13809e93f128303c914722cfba7 100644 (file)
--- a/clippy_lints/src/inherent_to_string.rs
+++ b/clippy_lints/src/inherent_to_string.rs
@@ -2,10 +2,11 @@
 use rustc_hir::{ImplItem, ImplItemKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::sym;
 
 use crate::utils::{
-    get_trait_def_id, implements_trait, match_type, paths, return_ty, span_lint_and_help, trait_ref_of_method,
-    walk_ptrs_ty,
+    get_trait_def_id, implements_trait, is_type_diagnostic_item, paths, return_ty, span_lint_and_help,
+    trait_ref_of_method,
 };
 
 declare_clippy_lint! {
@@ -92,25 +93,26 @@
 
 declare_lint_pass!(InherentToString => [INHERENT_TO_STRING, INHERENT_TO_STRING_SHADOW_DISPLAY]);
 
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InherentToString {
-    fn check_impl_item(&mut self, cx: &LateContext<'a, 'tcx>, impl_item: &'tcx ImplItem<'_>) {
+impl<'tcx> LateLintPass<'tcx> for InherentToString {
+    fn check_impl_item(&mut self, cx: &LateContext<'tcx>, impl_item: &'tcx ImplItem<'_>) {
         if impl_item.span.from_expansion() {
             return;
         }
 
         if_chain! {
             // Check if item is a method, called to_string and has a parameter 'self'
-            if let ImplItemKind::Method(ref signature, _) = impl_item.kind;
+            if let ImplItemKind::Fn(ref signature, _) = impl_item.kind;
             if impl_item.ident.name.as_str() == "to_string";
             let decl = &signature.decl;
             if decl.implicit_self.has_implicit_self();
             if decl.inputs.len() == 1;
+            if impl_item.generics.params.is_empty();
 
             // Check if return type is String
-            if match_type(cx, return_ty(cx, impl_item.hir_id), &paths::STRING);
+            if is_type_diagnostic_item(cx, return_ty(cx, impl_item.hir_id()), sym::string_type);
 
             // Filters instances of to_string which are required by a trait
-            if trait_ref_of_method(cx, impl_item.hir_id).is_none();
+            if trait_ref_of_method(cx, impl_item.hir_id()).is_none();
 
             then {
                 show_lint(cx, impl_item);
@@ -119,13 +121,12 @@ fn check_impl_item(&mut self, cx: &LateContext<'a, 'tcx>, impl_item: &'tcx ImplI
     }
 }
 
-fn show_lint(cx: &LateContext<'_, '_>, item: &ImplItem<'_>) {
+fn show_lint(cx: &LateContext<'_>, item: &ImplItem<'_>) {
     let display_trait_id = get_trait_def_id(cx, &paths::DISPLAY_TRAIT).expect("Failed to get trait ID of `Display`!");
 
     // Get the real type of 'self'
-    let fn_def_id = cx.tcx.hir().local_def_id(item.hir_id);
-    let self_type = cx.tcx.fn_sig(fn_def_id).input(0);
-    let self_type = walk_ptrs_ty(self_type.skip_binder());
+    let self_type = cx.tcx.fn_sig(item.def_id).input(0);
+    let self_type = self_type.skip_binder().peel_refs();
 
     // Emit either a warning or an error
     if implements_trait(cx, self_type, display_trait_id, &[]) {
@@ -137,7 +138,8 @@ fn show_lint(cx: &LateContext<'_, '_>, item: &ImplItem<'_>) {
                 "type `{}` implements inherent method `to_string(&self) -> String` which shadows the implementation of `Display`",
                 self_type.to_string()
             ),
-            &format!("remove the inherent method from type `{}`", self_type.to_string())
+            None,
+            &format!("remove the inherent method from type `{}`", self_type.to_string()),
         );
     } else {
         span_lint_and_help(
@@ -148,6 +150,7 @@ fn show_lint(cx: &LateContext<'_, '_>, item: &ImplItem<'_>) {
                 "implementation of inherent method `to_string(&self) -> String` for type `{}`",
                 self_type.to_string()
             ),
+            None,
             &format!("implement trait `Display` for type `{}` instead", self_type.to_string()),
         );
     }