diff --git a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index bfe806e8901f8..be8b3f0bc1e39 100644
--- a/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -2384,7 +2384,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         if let Some(body_expr) = finder.body_expr
             && let Some(loop_span) = finder.loop_span
             && let Some(def_id) = typeck_results.type_dependent_def_id(body_expr.hir_id)
-            && let Some(trait_did) = tcx.trait_of_item(def_id)
+            && let Some(trait_did) = tcx.trait_of_assoc(def_id)
             && tcx.is_diagnostic_item(sym::Iterator, trait_did)
         {
             if let Some(loop_bind) = finder.loop_bind {
diff --git a/compiler/rustc_borrowck/src/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
index ed4cd52ed9c82..56fdaf1c724ac 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -938,7 +938,7 @@ impl<'tcx> BorrowedContentSource<'tcx> {
     fn from_call(func: Ty<'tcx>, tcx: TyCtxt<'tcx>) -> Option<Self> {
         match *func.kind() {
             ty::FnDef(def_id, args) => {
-                let trait_id = tcx.trait_of_item(def_id)?;
+                let trait_id = tcx.trait_of_assoc(def_id)?;
 
                 if tcx.is_lang_item(trait_id, LangItem::Deref)
                     || tcx.is_lang_item(trait_id, LangItem::DerefMut)
diff --git a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
index a06540f832507..5d9416b59fcec 100644
--- a/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -682,7 +682,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         }
         let my_def = self.body.source.def_id();
         let Some(td) =
-            self.infcx.tcx.impl_of_method(my_def).and_then(|x| self.infcx.tcx.trait_id_of_impl(x))
+            self.infcx.tcx.impl_of_assoc(my_def).and_then(|x| self.infcx.tcx.trait_id_of_impl(x))
         else {
             return (false, false, None);
         };
@@ -880,7 +880,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                         let opt_suggestions = tcx
                             .typeck(path_segment.hir_id.owner.def_id)
                             .type_dependent_def_id(expr.hir_id)
-                            .and_then(|def_id| tcx.impl_of_method(def_id))
+                            .and_then(|def_id| tcx.impl_of_assoc(def_id))
                             .map(|def_id| tcx.associated_items(def_id))
                             .map(|assoc_items| {
                                 assoc_items
@@ -1056,7 +1056,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                         .tcx
                         .typeck(path_segment.hir_id.owner.def_id)
                         .type_dependent_def_id(cur_expr.hir_id)
-                        .and_then(|def_id| self.infcx.tcx.impl_of_method(def_id))
+                        .and_then(|def_id| self.infcx.tcx.impl_of_assoc(def_id))
                         .map(|def_id| self.infcx.tcx.associated_items(def_id))
                         .map(|assoc_items| {
                             assoc_items.filter_by_name_unhygienic(sym::iter_mut).peekable()
diff --git a/compiler/rustc_borrowck/src/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
index f363ef0a5a98f..f5fedbf95c1c1 100644
--- a/compiler/rustc_borrowck/src/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -1761,7 +1761,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypeChecker<'a, 'tcx> {
                 );
 
                 assert!(!matches!(
-                    tcx.impl_of_method(def_id).map(|imp| tcx.def_kind(imp)),
+                    tcx.impl_of_assoc(def_id).map(|imp| tcx.def_kind(imp)),
                     Some(DefKind::Impl { of_trait: true })
                 ));
                 self.prove_predicates(
diff --git a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
index 5ca2505cec43b..6cbf2dbf7d3fd 100644
--- a/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
+++ b/compiler/rustc_codegen_llvm/src/debuginfo/mod.rs
@@ -533,7 +533,7 @@ impl<'ll, 'tcx> DebugInfoCodegenMethods<'tcx> for CodegenCx<'ll, 'tcx> {
             // First, let's see if this is a method within an inherent impl. Because
             // if yes, we want to make the result subroutine DIE a child of the
             // subroutine's self-type.
-            if let Some(impl_def_id) = cx.tcx.impl_of_method(instance.def_id()) {
+            if let Some(impl_def_id) = cx.tcx.impl_of_assoc(instance.def_id()) {
                 // If the method does *not* belong to a trait, proceed
                 if cx.tcx.trait_id_of_impl(impl_def_id).is_none() {
                     let impl_self_ty = cx.tcx.instantiate_and_normalize_erasing_regions(
diff --git a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
index 2f5eca2d6b23e..297bdec2bc210 100644
--- a/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
+++ b/compiler/rustc_codegen_ssa/src/back/symbol_export.rs
@@ -86,7 +86,7 @@ fn reachable_non_generics_provider(tcx: TyCtxt<'_>, _: LocalCrate) -> DefIdMap<S
             // Only consider nodes that actually have exported symbols.
             match tcx.def_kind(def_id) {
                 DefKind::Fn | DefKind::Static { .. } => {}
-                DefKind::AssocFn if tcx.impl_of_method(def_id.to_def_id()).is_some() => {}
+                DefKind::AssocFn if tcx.impl_of_assoc(def_id.to_def_id()).is_some() => {}
                 _ => return None,
             };
 
diff --git a/compiler/rustc_const_eval/src/check_consts/check.rs b/compiler/rustc_const_eval/src/check_consts/check.rs
index 69637cadcc99f..44e5d1d5ee7ec 100644
--- a/compiler/rustc_const_eval/src/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/check_consts/check.rs
@@ -784,7 +784,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'_, 'tcx> {
                     self.revalidate_conditional_constness(callee, fn_args, *fn_span);
 
                 // Attempting to call a trait method?
-                if let Some(trait_did) = tcx.trait_of_item(callee) {
+                if let Some(trait_did) = tcx.trait_of_assoc(callee) {
                     // We can't determine the actual callee here, so we have to do different checks
                     // than usual.
 
diff --git a/compiler/rustc_const_eval/src/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/check_consts/qualifs.rs
index 166491b47a1fd..faf41f1658b70 100644
--- a/compiler/rustc_const_eval/src/check_consts/qualifs.rs
+++ b/compiler/rustc_const_eval/src/check_consts/qualifs.rs
@@ -369,7 +369,7 @@ where
         assert!(promoted.is_none() || Q::ALLOW_PROMOTED);
 
         // Don't peek inside trait associated constants.
-        if promoted.is_none() && cx.tcx.trait_of_item(def).is_none() {
+        if promoted.is_none() && cx.tcx.trait_of_assoc(def).is_none() {
             let qualifs = cx.tcx.at(constant.span).mir_const_qualif(def);
 
             if !Q::in_qualifs(&qualifs) {
diff --git a/compiler/rustc_const_eval/src/interpret/call.rs b/compiler/rustc_const_eval/src/interpret/call.rs
index bda00ea2fb88c..5b3adba02659c 100644
--- a/compiler/rustc_const_eval/src/interpret/call.rs
+++ b/compiler/rustc_const_eval/src/interpret/call.rs
@@ -725,7 +725,7 @@ impl<'tcx, M: Machine<'tcx>> InterpCx<'tcx, M> {
     ) {
         let tcx = *self.tcx;
 
-        let trait_def_id = tcx.trait_of_item(def_id).unwrap();
+        let trait_def_id = tcx.trait_of_assoc(def_id).unwrap();
         let virtual_trait_ref = ty::TraitRef::from_method(tcx, trait_def_id, virtual_instance.args);
         let existential_trait_ref = ty::ExistentialTraitRef::erase_self_ty(tcx, virtual_trait_ref);
         let concrete_trait_ref = existential_trait_ref.with_self_ty(tcx, dyn_ty);
diff --git a/compiler/rustc_hir/src/def.rs b/compiler/rustc_hir/src/def.rs
index ca57c4f31641d..3fee9af01b36f 100644
--- a/compiler/rustc_hir/src/def.rs
+++ b/compiler/rustc_hir/src/def.rs
@@ -295,6 +295,10 @@ impl DefKind {
         }
     }
 
+    pub fn is_assoc(self) -> bool {
+        matches!(self, DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy)
+    }
+
     /// This is a "module" in name resolution sense.
     #[inline]
     pub fn is_module_like(self) -> bool {
diff --git a/compiler/rustc_hir_analysis/src/errors/wrong_number_of_generic_args.rs b/compiler/rustc_hir_analysis/src/errors/wrong_number_of_generic_args.rs
index 2d60c9561a980..835f8e8cdaeed 100644
--- a/compiler/rustc_hir_analysis/src/errors/wrong_number_of_generic_args.rs
+++ b/compiler/rustc_hir_analysis/src/errors/wrong_number_of_generic_args.rs
@@ -759,7 +759,7 @@ impl<'a, 'tcx> WrongNumberOfGenericArgs<'a, 'tcx> {
         &self,
         err: &mut Diag<'_, impl EmissionGuarantee>,
     ) {
-        let trait_ = match self.tcx.trait_of_item(self.def_id) {
+        let trait_ = match self.tcx.trait_of_assoc(self.def_id) {
             Some(def_id) => def_id,
             None => return,
         };
diff --git a/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs b/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs
index 287a5532f0168..f73442fdebd4a 100644
--- a/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs
+++ b/compiler/rustc_hir_analysis/src/hir_ty_lowering/errors.rs
@@ -755,7 +755,7 @@ impl<'tcx> dyn HirTyLowerer<'tcx> + '_ {
         let limit = if candidates.len() == 5 { 5 } else { 4 };
 
         for (index, &item) in candidates.iter().take(limit).enumerate() {
-            let impl_ = tcx.impl_of_method(item).unwrap();
+            let impl_ = tcx.impl_of_assoc(item).unwrap();
 
             let note_span = if item.is_local() {
                 Some(tcx.def_span(item))
diff --git a/compiler/rustc_hir_typeck/src/fallback.rs b/compiler/rustc_hir_typeck/src/fallback.rs
index 759b5d9550c05..9406697dfed69 100644
--- a/compiler/rustc_hir_typeck/src/fallback.rs
+++ b/compiler/rustc_hir_typeck/src/fallback.rs
@@ -694,7 +694,7 @@ impl<'tcx> Visitor<'tcx> for AnnotateUnitFallbackVisitor<'_, 'tcx> {
         // i.e. changing `Default::default()` to `<() as Default>::default()`.
         if let hir::ExprKind::Path(hir::QPath::Resolved(None, path)) = expr.kind
             && let Res::Def(DefKind::AssocFn, def_id) = path.res
-            && self.fcx.tcx.trait_of_item(def_id).is_some()
+            && self.fcx.tcx.trait_of_assoc(def_id).is_some()
             && let Some(args) = self.fcx.typeck_results.borrow().node_args_opt(expr.hir_id)
             && let self_ty = args.type_at(0)
             && let Some(vid) = self.fcx.root_vid(self_ty)
diff --git a/compiler/rustc_lint/src/map_unit_fn.rs b/compiler/rustc_lint/src/map_unit_fn.rs
index a8803158889f5..34210137bde18 100644
--- a/compiler/rustc_lint/src/map_unit_fn.rs
+++ b/compiler/rustc_lint/src/map_unit_fn.rs
@@ -96,7 +96,7 @@ impl<'tcx> LateLintPass<'tcx> for MapUnitFn {
 
 fn is_impl_slice(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
     {
         return cx.tcx.type_of(impl_id).skip_binder().is_slice();
     }
diff --git a/compiler/rustc_lint/src/noop_method_call.rs b/compiler/rustc_lint/src/noop_method_call.rs
index b7835e6c36ab1..24682c4562a03 100644
--- a/compiler/rustc_lint/src/noop_method_call.rs
+++ b/compiler/rustc_lint/src/noop_method_call.rs
@@ -84,7 +84,7 @@ impl<'tcx> LateLintPass<'tcx> for NoopMethodCall {
             return;
         };
 
-        let Some(trait_id) = cx.tcx.trait_of_item(did) else { return };
+        let Some(trait_id) = cx.tcx.trait_of_assoc(did) else { return };
 
         let Some(trait_) = cx.tcx.get_diagnostic_name(trait_id) else { return };
 
diff --git a/compiler/rustc_lint/src/pass_by_value.rs b/compiler/rustc_lint/src/pass_by_value.rs
index d3b3b55dd4c48..a3cf3d568b1c9 100644
--- a/compiler/rustc_lint/src/pass_by_value.rs
+++ b/compiler/rustc_lint/src/pass_by_value.rs
@@ -24,7 +24,7 @@ impl<'tcx> LateLintPass<'tcx> for PassByValue {
     fn check_ty(&mut self, cx: &LateContext<'_>, ty: &'tcx hir::Ty<'tcx, AmbigArg>) {
         match &ty.kind {
             TyKind::Ref(_, hir::MutTy { ty: inner_ty, mutbl: hir::Mutability::Not }) => {
-                if let Some(impl_did) = cx.tcx.impl_of_method(ty.hir_id.owner.to_def_id()) {
+                if let Some(impl_did) = cx.tcx.impl_of_assoc(ty.hir_id.owner.to_def_id()) {
                     if cx.tcx.impl_trait_ref(impl_did).is_some() {
                         return;
                     }
diff --git a/compiler/rustc_lint/src/types.rs b/compiler/rustc_lint/src/types.rs
index fc9d795cb2315..b0afc333ebe2f 100644
--- a/compiler/rustc_lint/src/types.rs
+++ b/compiler/rustc_lint/src/types.rs
@@ -1904,7 +1904,7 @@ impl InvalidAtomicOrdering {
         if let ExprKind::MethodCall(method_path, _, args, _) = &expr.kind
             && recognized_names.contains(&method_path.ident.name)
             && let Some(m_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-            && let Some(impl_did) = cx.tcx.impl_of_method(m_def_id)
+            && let Some(impl_did) = cx.tcx.impl_of_assoc(m_def_id)
             && let Some(adt) = cx.tcx.type_of(impl_did).instantiate_identity().ty_adt_def()
             // skip extension traits, only lint functions from the standard library
             && cx.tcx.trait_id_of_impl(impl_did).is_none()
diff --git a/compiler/rustc_middle/src/middle/privacy.rs b/compiler/rustc_middle/src/middle/privacy.rs
index 03549091d62d3..785ddd1ee2980 100644
--- a/compiler/rustc_middle/src/middle/privacy.rs
+++ b/compiler/rustc_middle/src/middle/privacy.rs
@@ -182,7 +182,7 @@ impl EffectiveVisibilities {
             // don't check this condition for them.
             let is_impl = matches!(tcx.def_kind(def_id), DefKind::Impl { .. });
             let is_associated_item_in_trait_impl = tcx
-                .impl_of_method(def_id.to_def_id())
+                .impl_of_assoc(def_id.to_def_id())
                 .and_then(|impl_id| tcx.trait_id_of_impl(impl_id))
                 .is_some();
             if !is_impl && !is_associated_item_in_trait_impl {
diff --git a/compiler/rustc_middle/src/ty/mod.rs b/compiler/rustc_middle/src/ty/mod.rs
index 4c95f0748d327..bb70c61cd1417 100644
--- a/compiler/rustc_middle/src/ty/mod.rs
+++ b/compiler/rustc_middle/src/ty/mod.rs
@@ -1988,29 +1988,21 @@ impl<'tcx> TyCtxt<'tcx> {
         self.impl_trait_ref(def_id).map(|tr| tr.skip_binder().def_id)
     }
 
-    /// If the given `DefId` describes an item belonging to a trait,
-    /// returns the `DefId` of the trait that the trait item belongs to;
-    /// otherwise, returns `None`.
-    pub fn trait_of_item(self, def_id: DefId) -> Option<DefId> {
-        if let DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy = self.def_kind(def_id) {
-            let parent = self.parent(def_id);
-            if let DefKind::Trait | DefKind::TraitAlias = self.def_kind(parent) {
-                return Some(parent);
-            }
-        }
-        None
+    /// If the given `DefId` is an associated item, returns the `DefId` of the parent trait or impl.
+    pub fn assoc_parent(self, def_id: DefId) -> Option<DefId> {
+        self.def_kind(def_id).is_assoc().then(|| self.parent(def_id))
     }
 
-    /// If the given `DefId` describes a method belonging to an impl, returns the
-    /// `DefId` of the impl that the method belongs to; otherwise, returns `None`.
-    pub fn impl_of_method(self, def_id: DefId) -> Option<DefId> {
-        if let DefKind::AssocConst | DefKind::AssocFn | DefKind::AssocTy = self.def_kind(def_id) {
-            let parent = self.parent(def_id);
-            if let DefKind::Impl { .. } = self.def_kind(parent) {
-                return Some(parent);
-            }
-        }
-        None
+    /// If the given `DefId` is an associated item of a trait,
+    /// returns the `DefId` of the trait; otherwise, returns `None`.
+    pub fn trait_of_assoc(self, def_id: DefId) -> Option<DefId> {
+        self.assoc_parent(def_id).filter(|id| self.def_kind(id) == DefKind::Trait)
+    }
+
+    /// If the given `DefId` is an associated item of an impl,
+    /// returns the `DefId` of the impl; otherwise returns `None`.
+    pub fn impl_of_assoc(self, def_id: DefId) -> Option<DefId> {
+        self.assoc_parent(def_id).filter(|id| matches!(self.def_kind(id), DefKind::Impl { .. }))
     }
 
     pub fn is_exportable(self, def_id: DefId) -> bool {
@@ -2181,7 +2173,7 @@ impl<'tcx> TyCtxt<'tcx> {
 
     #[inline]
     pub fn is_const_default_method(self, def_id: DefId) -> bool {
-        matches!(self.trait_of_item(def_id), Some(trait_id) if self.is_const_trait(trait_id))
+        matches!(self.trait_of_assoc(def_id), Some(trait_id) if self.is_const_trait(trait_id))
     }
 
     pub fn impl_method_has_trait_impl_trait_tys(self, def_id: DefId) -> bool {
diff --git a/compiler/rustc_mir_transform/src/check_call_recursion.rs b/compiler/rustc_mir_transform/src/check_call_recursion.rs
index cace4cd6bba56..6d61ac2dd8037 100644
--- a/compiler/rustc_mir_transform/src/check_call_recursion.rs
+++ b/compiler/rustc_mir_transform/src/check_call_recursion.rs
@@ -21,7 +21,7 @@ impl<'tcx> MirLint<'tcx> for CheckCallRecursion {
 
         if let DefKind::Fn | DefKind::AssocFn = tcx.def_kind(def_id) {
             // If this is trait/impl method, extract the trait's args.
-            let trait_args = match tcx.trait_of_item(def_id.to_def_id()) {
+            let trait_args = match tcx.trait_of_assoc(def_id.to_def_id()) {
                 Some(trait_def_id) => {
                     let trait_args_count = tcx.generics_of(trait_def_id).count();
                     &GenericArgs::identity_for_item(tcx, def_id)[..trait_args_count]
@@ -44,7 +44,7 @@ impl<'tcx> MirLint<'tcx> for CheckDropRecursion {
         // First check if `body` is an `fn drop()` of `Drop`
         if let DefKind::AssocFn = tcx.def_kind(def_id)
         && let Some(trait_ref) =
-            tcx.impl_of_method(def_id.to_def_id()).and_then(|def_id| tcx.impl_trait_ref(def_id))
+            tcx.impl_of_assoc(def_id.to_def_id()).and_then(|def_id| tcx.impl_trait_ref(def_id))
         && tcx.is_lang_item(trait_ref.instantiate_identity().def_id, LangItem::Drop)
         // avoid erroneous `Drop` impls from causing ICEs below
         && let sig = tcx.fn_sig(def_id).instantiate_identity()
diff --git a/compiler/rustc_mir_transform/src/check_packed_ref.rs b/compiler/rustc_mir_transform/src/check_packed_ref.rs
index e9b85ba6e9db8..dcb812c78993e 100644
--- a/compiler/rustc_mir_transform/src/check_packed_ref.rs
+++ b/compiler/rustc_mir_transform/src/check_packed_ref.rs
@@ -40,7 +40,7 @@ impl<'tcx> Visitor<'tcx> for PackedRefChecker<'_, 'tcx> {
         if context.is_borrow() && util::is_disaligned(self.tcx, self.body, self.typing_env, *place)
         {
             let def_id = self.body.source.instance.def_id();
-            if let Some(impl_def_id) = self.tcx.impl_of_method(def_id)
+            if let Some(impl_def_id) = self.tcx.impl_of_assoc(def_id)
                 && self.tcx.is_builtin_derived(impl_def_id)
             {
                 // If we ever reach here it means that the generated derive
diff --git a/compiler/rustc_mir_transform/src/coverage/query.rs b/compiler/rustc_mir_transform/src/coverage/query.rs
index 986c001de5e80..551f720c869e8 100644
--- a/compiler/rustc_mir_transform/src/coverage/query.rs
+++ b/compiler/rustc_mir_transform/src/coverage/query.rs
@@ -35,7 +35,7 @@ fn is_eligible_for_coverage(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
     // Don't instrument functions with `#[automatically_derived]` on their
     // enclosing impl block, on the assumption that most users won't care about
     // coverage for derived impls.
-    if let Some(impl_of) = tcx.impl_of_method(def_id.to_def_id())
+    if let Some(impl_of) = tcx.impl_of_assoc(def_id.to_def_id())
         && tcx.is_automatically_derived(impl_of)
     {
         trace!("InstrumentCoverage skipped for {def_id:?} (automatically derived)");
diff --git a/compiler/rustc_mir_transform/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs
index 6c65b072bec08..c687036f544dc 100644
--- a/compiler/rustc_mir_transform/src/shim.rs
+++ b/compiler/rustc_mir_transform/src/shim.rs
@@ -75,7 +75,7 @@ fn make_shim<'tcx>(tcx: TyCtxt<'tcx>, instance: ty::InstanceKind<'tcx>) -> Body<
             build_call_shim(tcx, instance, Some(adjustment), CallKind::Direct(def_id))
         }
         ty::InstanceKind::FnPtrShim(def_id, ty) => {
-            let trait_ = tcx.trait_of_item(def_id).unwrap();
+            let trait_ = tcx.trait_of_assoc(def_id).unwrap();
             // Supports `Fn` or `async Fn` traits.
             let adjustment = match tcx
                 .fn_trait_kind_from_def_id(trait_)
diff --git a/compiler/rustc_monomorphize/src/partitioning.rs b/compiler/rustc_monomorphize/src/partitioning.rs
index f3e7d582781d5..cee15e0f6969f 100644
--- a/compiler/rustc_monomorphize/src/partitioning.rs
+++ b/compiler/rustc_monomorphize/src/partitioning.rs
@@ -650,13 +650,13 @@ fn characteristic_def_id_of_mono_item<'tcx>(
             // its self-type. If the self-type does not provide a characteristic
             // DefId, we use the location of the impl after all.
 
-            if tcx.trait_of_item(def_id).is_some() {
+            if tcx.trait_of_assoc(def_id).is_some() {
                 let self_ty = instance.args.type_at(0);
                 // This is a default implementation of a trait method.
                 return characteristic_def_id_of_type(self_ty).or(Some(def_id));
             }
 
-            if let Some(impl_def_id) = tcx.impl_of_method(def_id) {
+            if let Some(impl_def_id) = tcx.impl_of_assoc(def_id) {
                 if tcx.sess.opts.incremental.is_some()
                     && tcx
                         .trait_id_of_impl(impl_def_id)
diff --git a/compiler/rustc_passes/src/dead.rs b/compiler/rustc_passes/src/dead.rs
index d987041fe0e09..a90d1af87ca19 100644
--- a/compiler/rustc_passes/src/dead.rs
+++ b/compiler/rustc_passes/src/dead.rs
@@ -368,7 +368,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
     /// will be ignored for the purposes of dead code analysis (see PR #85200
     /// for discussion).
     fn should_ignore_item(&mut self, def_id: DefId) -> bool {
-        if let Some(impl_of) = self.tcx.impl_of_method(def_id) {
+        if let Some(impl_of) = self.tcx.impl_of_assoc(def_id) {
             if !self.tcx.is_automatically_derived(impl_of) {
                 return false;
             }
@@ -429,7 +429,7 @@ impl<'tcx> MarkSymbolVisitor<'tcx> {
             Node::TraitItem(trait_item) => {
                 // mark the trait live
                 let trait_item_id = trait_item.owner_id.to_def_id();
-                if let Some(trait_id) = self.tcx.trait_of_item(trait_item_id) {
+                if let Some(trait_id) = self.tcx.trait_of_assoc(trait_item_id) {
                     self.check_def_id(trait_id);
                 }
                 intravisit::walk_trait_item(self, trait_item);
diff --git a/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs b/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs
index c69991f3fb208..52717d73b8aed 100644
--- a/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs
+++ b/compiler/rustc_sanitizers/src/cfi/typeid/itanium_cxx_abi/transform.rs
@@ -339,7 +339,7 @@ pub(crate) fn transform_instance<'tcx>(
     } else if let ty::InstanceKind::Virtual(def_id, _) = instance.def {
         // Transform self into a trait object of the trait that defines the method for virtual
         // functions to match the type erasure done below.
-        let upcast_ty = match tcx.trait_of_item(def_id) {
+        let upcast_ty = match tcx.trait_of_assoc(def_id) {
             Some(trait_id) => trait_object_ty(
                 tcx,
                 ty::Binder::dummy(ty::TraitRef::from_method(tcx, trait_id, instance.args)),
@@ -364,7 +364,7 @@ pub(crate) fn transform_instance<'tcx>(
         };
         instance.args = tcx.mk_args_trait(self_ty, instance.args.into_iter().skip(1));
     } else if let ty::InstanceKind::VTableShim(def_id) = instance.def
-        && let Some(trait_id) = tcx.trait_of_item(def_id)
+        && let Some(trait_id) = tcx.trait_of_assoc(def_id)
     {
         // Adjust the type ids of VTableShims to the type id expected in the call sites for the
         // entry in the vtable (i.e., by using the signature of the closure passed as an argument
@@ -466,7 +466,7 @@ fn implemented_method<'tcx>(
     let method_id;
     let trait_id;
     let trait_method;
-    let ancestor = if let Some(impl_id) = tcx.impl_of_method(instance.def_id()) {
+    let ancestor = if let Some(impl_id) = tcx.impl_of_assoc(instance.def_id()) {
         // Implementation in an `impl` block
         trait_ref = tcx.impl_trait_ref(impl_id)?;
         let impl_method = tcx.associated_item(instance.def_id());
@@ -480,7 +480,7 @@ fn implemented_method<'tcx>(
         // Provided method in a `trait` block
         trait_method = trait_method_bound;
         method_id = instance.def_id();
-        trait_id = tcx.trait_of_item(method_id)?;
+        trait_id = tcx.trait_of_assoc(method_id)?;
         trait_ref = ty::EarlyBinder::bind(TraitRef::from_method(tcx, trait_id, instance.args));
         trait_id
     } else {
diff --git a/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs b/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs
index 1db05ced8d2fb..022d549a9df80 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/infer/need_type_info.rs
@@ -1303,7 +1303,7 @@ impl<'a, 'tcx> Visitor<'tcx> for FindInferSourceVisitor<'a, 'tcx> {
             && let Some(args) = self.node_args_opt(expr.hir_id)
             && args.iter().any(|arg| self.generic_arg_contains_target(arg))
             && let Some(def_id) = self.typeck_results.type_dependent_def_id(expr.hir_id)
-            && self.tecx.tcx.trait_of_item(def_id).is_some()
+            && self.tecx.tcx.trait_of_assoc(def_id).is_some()
             && !has_impl_trait(def_id)
             // FIXME(fn_delegation): In delegation item argument spans are equal to last path
             // segment. This leads to ICE's when emitting `multipart_suggestion`.
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs
index 98f67257fd137..cdf1402252aa0 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/ambiguity.rs
@@ -360,7 +360,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                             },
                         ] = path.segments
                         && data.trait_ref.def_id == *trait_id
-                        && self.tcx.trait_of_item(*item_id) == Some(*trait_id)
+                        && self.tcx.trait_of_assoc(*item_id) == Some(*trait_id)
                         && let None = self.tainted_by_errors()
                     {
                         let assoc_item = self.tcx.associated_item(item_id);
diff --git a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs
index c524873636649..c182fd99b17bd 100644
--- a/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs
+++ b/compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs
@@ -987,7 +987,7 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
                     else {
                         return false;
                     };
-                    if self.tcx.trait_of_item(did) != Some(clone_trait) {
+                    if self.tcx.trait_of_assoc(did) != Some(clone_trait) {
                         return false;
                     }
                     Some(ident.span)
diff --git a/compiler/rustc_trait_selection/src/traits/mod.rs b/compiler/rustc_trait_selection/src/traits/mod.rs
index 91c41544f78ff..9b5e59ce0fdb7 100644
--- a/compiler/rustc_trait_selection/src/traits/mod.rs
+++ b/compiler/rustc_trait_selection/src/traits/mod.rs
@@ -759,7 +759,7 @@ fn instantiate_and_check_impossible_predicates<'tcx>(
 
     // Specifically check trait fulfillment to avoid an error when trying to resolve
     // associated items.
-    if let Some(trait_def_id) = tcx.trait_of_item(key.0) {
+    if let Some(trait_def_id) = tcx.trait_of_assoc(key.0) {
         let trait_ref = ty::TraitRef::from_method(tcx, trait_def_id, key.1);
         predicates.push(trait_ref.upcast(tcx));
     }
diff --git a/compiler/rustc_trait_selection/src/traits/project.rs b/compiler/rustc_trait_selection/src/traits/project.rs
index 28b5b7cf391eb..581191b2036d2 100644
--- a/compiler/rustc_trait_selection/src/traits/project.rs
+++ b/compiler/rustc_trait_selection/src/traits/project.rs
@@ -1507,7 +1507,7 @@ fn confirm_builtin_candidate<'cx, 'tcx>(
     let tcx = selcx.tcx();
     let self_ty = obligation.predicate.self_ty();
     let item_def_id = obligation.predicate.def_id;
-    let trait_def_id = tcx.trait_of_item(item_def_id).unwrap();
+    let trait_def_id = tcx.trait_of_assoc(item_def_id).unwrap();
     let args = tcx.mk_args(&[self_ty.into()]);
     let (term, obligations) = if tcx.is_lang_item(trait_def_id, LangItem::DiscriminantKind) {
         let discriminant_def_id =
diff --git a/compiler/rustc_ty_utils/src/instance.rs b/compiler/rustc_ty_utils/src/instance.rs
index 166e8f1934299..e6c3568620b5d 100644
--- a/compiler/rustc_ty_utils/src/instance.rs
+++ b/compiler/rustc_ty_utils/src/instance.rs
@@ -21,7 +21,7 @@ fn resolve_instance_raw<'tcx>(
 ) -> Result<Option<Instance<'tcx>>, ErrorGuaranteed> {
     let PseudoCanonicalInput { typing_env, value: (def_id, args) } = key;
 
-    let result = if let Some(trait_def_id) = tcx.trait_of_item(def_id) {
+    let result = if let Some(trait_def_id) = tcx.trait_of_assoc(def_id) {
         debug!(" => associated item, attempting to find impl in typing_env {:#?}", typing_env);
         resolve_associated_item(
             tcx,
diff --git a/src/tools/clippy/clippy_lints/src/assigning_clones.rs b/src/tools/clippy/clippy_lints/src/assigning_clones.rs
index 8b8b42bbf7228..52287be34c784 100644
--- a/src/tools/clippy/clippy_lints/src/assigning_clones.rs
+++ b/src/tools/clippy/clippy_lints/src/assigning_clones.rs
@@ -98,7 +98,7 @@ impl<'tcx> LateLintPass<'tcx> for AssigningClones {
             // That is overly conservative - the lint should fire even if there was no initializer,
             // but the variable has been initialized before `lhs` was evaluated.
             && path_to_local(lhs).is_none_or(|lhs| local_is_initialized(cx, lhs))
-            && let Some(resolved_impl) = cx.tcx.impl_of_method(resolved_fn.def_id())
+            && let Some(resolved_impl) = cx.tcx.impl_of_assoc(resolved_fn.def_id())
             // Derived forms don't implement `clone_from`/`clone_into`.
             // See https://github.com/rust-lang/rust/pull/98445#issuecomment-1190681305
             && !cx.tcx.is_builtin_derived(resolved_impl)
diff --git a/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs b/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs
index e4dafde0f9df7..a1543cabd2f9d 100644
--- a/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/cast_ptr_alignment.rs
@@ -63,7 +63,7 @@ fn is_used_as_unaligned(cx: &LateContext<'_>, e: &Expr<'_>) -> bool {
         ExprKind::MethodCall(name, self_arg, ..) if self_arg.hir_id == e.hir_id => {
             if matches!(name.ident.name, sym::read_unaligned | sym::write_unaligned)
                 && let Some(def_id) = cx.typeck_results().type_dependent_def_id(parent.hir_id)
-                && let Some(def_id) = cx.tcx.impl_of_method(def_id)
+                && let Some(def_id) = cx.tcx.impl_of_assoc(def_id)
                 && cx.tcx.type_of(def_id).instantiate_identity().is_raw_ptr()
             {
                 true
diff --git a/src/tools/clippy/clippy_lints/src/casts/confusing_method_to_numeric_cast.rs b/src/tools/clippy/clippy_lints/src/casts/confusing_method_to_numeric_cast.rs
index 849de22cfbaa8..73347e7141eb4 100644
--- a/src/tools/clippy/clippy_lints/src/casts/confusing_method_to_numeric_cast.rs
+++ b/src/tools/clippy/clippy_lints/src/casts/confusing_method_to_numeric_cast.rs
@@ -37,7 +37,7 @@ fn get_const_name_and_ty_name(
         } else {
             return None;
         }
-    } else if let Some(impl_id) = cx.tcx.impl_of_method(method_def_id)
+    } else if let Some(impl_id) = cx.tcx.impl_of_assoc(method_def_id)
         && let Some(ty_name) = get_primitive_ty_name(cx.tcx.type_of(impl_id).instantiate_identity())
         && matches!(
             method_name,
diff --git a/src/tools/clippy/clippy_lints/src/dereference.rs b/src/tools/clippy/clippy_lints/src/dereference.rs
index 5099df3fa0239..995a1209595e9 100644
--- a/src/tools/clippy/clippy_lints/src/dereference.rs
+++ b/src/tools/clippy/clippy_lints/src/dereference.rs
@@ -364,7 +364,7 @@ impl<'tcx> LateLintPass<'tcx> for Dereferencing<'tcx> {
                                 // * `&self` methods on `&T` can have auto-borrow, but `&self` methods on `T` will take
                                 //   priority.
                                 if let Some(fn_id) = typeck.type_dependent_def_id(hir_id)
-                                    && let Some(trait_id) = cx.tcx.trait_of_item(fn_id)
+                                    && let Some(trait_id) = cx.tcx.trait_of_assoc(fn_id)
                                     && let arg_ty = cx.tcx.erase_regions(adjusted_ty)
                                     && let ty::Ref(_, sub_ty, _) = *arg_ty.kind()
                                     && let args =
diff --git a/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs b/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
index c743501da253e..c634c12e1877b 100644
--- a/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
+++ b/src/tools/clippy/clippy_lints/src/implicit_saturating_sub.rs
@@ -339,7 +339,7 @@ fn check_with_condition<'tcx>(
             ExprKind::Path(QPath::TypeRelative(_, name)) => {
                 if name.ident.name == sym::MIN
                     && let Some(const_id) = cx.typeck_results().type_dependent_def_id(cond_num_val.hir_id)
-                    && let Some(impl_id) = cx.tcx.impl_of_method(const_id)
+                    && let Some(impl_id) = cx.tcx.impl_of_assoc(const_id)
                     && let None = cx.tcx.impl_trait_ref(impl_id) // An inherent impl
                     && cx.tcx.type_of(impl_id).instantiate_identity().is_integral()
                 {
@@ -350,7 +350,7 @@ fn check_with_condition<'tcx>(
                 if let ExprKind::Path(QPath::TypeRelative(_, name)) = func.kind
                     && name.ident.name == sym::min_value
                     && let Some(func_id) = cx.typeck_results().type_dependent_def_id(func.hir_id)
-                    && let Some(impl_id) = cx.tcx.impl_of_method(func_id)
+                    && let Some(impl_id) = cx.tcx.impl_of_assoc(func_id)
                     && let None = cx.tcx.impl_trait_ref(impl_id) // An inherent impl
                     && cx.tcx.type_of(impl_id).instantiate_identity().is_integral()
                 {
diff --git a/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs b/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
index 972b0b110e0e9..7bb684d65bb42 100644
--- a/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
+++ b/src/tools/clippy/clippy_lints/src/loops/needless_range_loop.rs
@@ -317,7 +317,7 @@ impl<'tcx> Visitor<'tcx> for VarVisitor<'_, 'tcx> {
                 .cx
                 .typeck_results()
                 .type_dependent_def_id(expr.hir_id)
-                .and_then(|def_id| self.cx.tcx.trait_of_item(def_id))
+                .and_then(|def_id| self.cx.tcx.trait_of_assoc(def_id))
             && ((meth.ident.name == sym::index && self.cx.tcx.lang_items().index_trait() == Some(trait_id))
                 || (meth.ident.name == sym::index_mut && self.cx.tcx.lang_items().index_mut_trait() == Some(trait_id)))
             && !self.check(args_1, args_0, expr)
diff --git a/src/tools/clippy/clippy_lints/src/methods/bytes_count_to_len.rs b/src/tools/clippy/clippy_lints/src/methods/bytes_count_to_len.rs
index a9f6a41c2357d..b8cc5ddd845c9 100644
--- a/src/tools/clippy/clippy_lints/src/methods/bytes_count_to_len.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/bytes_count_to_len.rs
@@ -14,7 +14,7 @@ pub(super) fn check<'tcx>(
     bytes_recv: &'tcx hir::Expr<'_>,
 ) {
     if let Some(bytes_id) = cx.typeck_results().type_dependent_def_id(count_recv.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(bytes_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(bytes_id)
         && cx.tcx.type_of(impl_id).instantiate_identity().is_str()
         && let ty = cx.typeck_results().expr_ty(bytes_recv).peel_refs()
         && (ty.is_str() || is_type_lang_item(cx, ty, hir::LangItem::String))
diff --git a/src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs b/src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs
index 292fa08b59843..6f9702f6c6c33 100644
--- a/src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/case_sensitive_file_extension_comparisons.rs
@@ -30,7 +30,7 @@ pub(super) fn check<'tcx>(
     }
 
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && cx.tcx.type_of(impl_id).instantiate_identity().is_str()
         && let ExprKind::Lit(Spanned {
             node: LitKind::Str(ext_literal, ..),
diff --git a/src/tools/clippy/clippy_lints/src/methods/clone_on_copy.rs b/src/tools/clippy/clippy_lints/src/methods/clone_on_copy.rs
index 2ecf3eb897988..0a456d1057ad9 100644
--- a/src/tools/clippy/clippy_lints/src/methods/clone_on_copy.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/clone_on_copy.rs
@@ -28,7 +28,7 @@ pub(super) fn check(
     if cx
         .typeck_results()
         .type_dependent_def_id(expr.hir_id)
-        .and_then(|id| cx.tcx.trait_of_item(id))
+        .and_then(|id| cx.tcx.trait_of_assoc(id))
         .zip(cx.tcx.lang_items().clone_trait())
         .is_none_or(|(x, y)| x != y)
     {
diff --git a/src/tools/clippy/clippy_lints/src/methods/get_first.rs b/src/tools/clippy/clippy_lints/src/methods/get_first.rs
index f4465e654c2e1..2e1d71ce284d6 100644
--- a/src/tools/clippy/clippy_lints/src/methods/get_first.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/get_first.rs
@@ -18,7 +18,7 @@ pub(super) fn check<'tcx>(
     arg: &'tcx hir::Expr<'_>,
 ) {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && let identity = cx.tcx.type_of(impl_id).instantiate_identity()
         && let hir::ExprKind::Lit(Spanned {
             node: LitKind::Int(Pu128(0), _),
diff --git a/src/tools/clippy/clippy_lints/src/methods/implicit_clone.rs b/src/tools/clippy/clippy_lints/src/methods/implicit_clone.rs
index 9724463f0c084..efa8cee58df72 100644
--- a/src/tools/clippy/clippy_lints/src/methods/implicit_clone.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/implicit_clone.rs
@@ -50,7 +50,7 @@ pub fn is_clone_like(cx: &LateContext<'_>, method_name: Symbol, method_def_id: h
         sym::to_path_buf => is_diag_item_method(cx, method_def_id, sym::Path),
         sym::to_vec => cx
             .tcx
-            .impl_of_method(method_def_id)
+            .impl_of_assoc(method_def_id)
             .filter(|&impl_did| {
                 cx.tcx.type_of(impl_did).instantiate_identity().is_slice() && cx.tcx.impl_trait_ref(impl_did).is_none()
             })
diff --git a/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs b/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs
index f5fe4316eb0d3..f851ebe91f37f 100644
--- a/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/iter_overeager_cloned.rs
@@ -44,9 +44,9 @@ pub(super) fn check<'tcx>(
     let typeck = cx.typeck_results();
     if let Some(iter_id) = cx.tcx.get_diagnostic_item(sym::Iterator)
         && let Some(method_id) = typeck.type_dependent_def_id(expr.hir_id)
-        && cx.tcx.trait_of_item(method_id) == Some(iter_id)
+        && cx.tcx.trait_of_assoc(method_id) == Some(iter_id)
         && let Some(method_id) = typeck.type_dependent_def_id(cloned_call.hir_id)
-        && cx.tcx.trait_of_item(method_id) == Some(iter_id)
+        && cx.tcx.trait_of_assoc(method_id) == Some(iter_id)
         && let cloned_recv_ty = typeck.expr_ty_adjusted(cloned_recv)
         && let Some(iter_assoc_ty) = cx.get_associated_type(cloned_recv_ty, iter_id, sym::Item)
         && matches!(*iter_assoc_ty.kind(), ty::Ref(_, ty, _) if !is_copy(cx, ty))
diff --git a/src/tools/clippy/clippy_lints/src/methods/manual_ok_or.rs b/src/tools/clippy/clippy_lints/src/methods/manual_ok_or.rs
index c286c5faaed3e..077957fa44dc8 100644
--- a/src/tools/clippy/clippy_lints/src/methods/manual_ok_or.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/manual_ok_or.rs
@@ -18,7 +18,7 @@ pub(super) fn check<'tcx>(
     map_expr: &'tcx Expr<'_>,
 ) {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id).instantiate_identity(), sym::Option)
         && let ExprKind::Call(err_path, [err_arg]) = or_expr.kind
         && is_res_lang_ctor(cx, path_res(cx, err_path), ResultErr)
diff --git a/src/tools/clippy/clippy_lints/src/methods/manual_str_repeat.rs b/src/tools/clippy/clippy_lints/src/methods/manual_str_repeat.rs
index 8167e4f960534..a811dd1cee18f 100644
--- a/src/tools/clippy/clippy_lints/src/methods/manual_str_repeat.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/manual_str_repeat.rs
@@ -59,7 +59,7 @@ pub(super) fn check(
         && is_type_lang_item(cx, cx.typeck_results().expr_ty(collect_expr), LangItem::String)
         && let Some(take_id) = cx.typeck_results().type_dependent_def_id(take_expr.hir_id)
         && let Some(iter_trait_id) = cx.tcx.get_diagnostic_item(sym::Iterator)
-        && cx.tcx.trait_of_item(take_id) == Some(iter_trait_id)
+        && cx.tcx.trait_of_assoc(take_id) == Some(iter_trait_id)
         && let Some(repeat_kind) = parse_repeat_arg(cx, repeat_arg)
         && let ctxt = collect_expr.span.ctxt()
         && ctxt == take_expr.span.ctxt()
diff --git a/src/tools/clippy/clippy_lints/src/methods/map_clone.rs b/src/tools/clippy/clippy_lints/src/methods/map_clone.rs
index 333a33f7527d6..748be9bfcc626 100644
--- a/src/tools/clippy/clippy_lints/src/methods/map_clone.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/map_clone.rs
@@ -23,7 +23,7 @@ fn should_run_lint(cx: &LateContext<'_>, e: &hir::Expr<'_>, method_id: DefId) ->
         return true;
     }
     // We check if it's an `Option` or a `Result`.
-    if let Some(id) = cx.tcx.impl_of_method(method_id) {
+    if let Some(id) = cx.tcx.impl_of_assoc(method_id) {
         let identity = cx.tcx.type_of(id).instantiate_identity();
         if !is_type_diagnostic_item(cx, identity, sym::Option) && !is_type_diagnostic_item(cx, identity, sym::Result) {
             return false;
@@ -69,7 +69,7 @@ pub(super) fn check(cx: &LateContext<'_>, e: &hir::Expr<'_>, recv: &hir::Expr<'_
                             hir::ExprKind::MethodCall(method, obj, [], _) => {
                                 if ident_eq(name, obj) && method.ident.name == sym::clone
                                 && let Some(fn_id) = cx.typeck_results().type_dependent_def_id(closure_expr.hir_id)
-                                && let Some(trait_id) = cx.tcx.trait_of_item(fn_id)
+                                && let Some(trait_id) = cx.tcx.trait_of_assoc(fn_id)
                                 && cx.tcx.lang_items().clone_trait() == Some(trait_id)
                                 // no autoderefs
                                 && !cx.typeck_results().expr_adjustments(obj).iter()
diff --git a/src/tools/clippy/clippy_lints/src/methods/map_err_ignore.rs b/src/tools/clippy/clippy_lints/src/methods/map_err_ignore.rs
index 5d0d4dae35fa1..41beda9c5cb4a 100644
--- a/src/tools/clippy/clippy_lints/src/methods/map_err_ignore.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/map_err_ignore.rs
@@ -8,7 +8,7 @@ use super::MAP_ERR_IGNORE;
 
 pub(super) fn check(cx: &LateContext<'_>, e: &Expr<'_>, arg: &Expr<'_>) {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(e.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id).instantiate_identity(), sym::Result)
         && let ExprKind::Closure(&Closure {
             capture_clause: CaptureBy::Ref,
diff --git a/src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs b/src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs
index 320523aceb675..4235af882b0c7 100644
--- a/src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs
@@ -13,7 +13,7 @@ pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, ex: &'tcx Expr<'tcx>, recv: &'
         && let (_, ref_depth, Mutability::Mut) = peel_mid_ty_refs_is_mutable(cx.typeck_results().expr_ty(recv))
         && ref_depth >= 1
         && let Some(method_id) = cx.typeck_results().type_dependent_def_id(ex.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id).instantiate_identity(), sym::Mutex)
     {
         span_lint_and_sugg(
diff --git a/src/tools/clippy/clippy_lints/src/methods/open_options.rs b/src/tools/clippy/clippy_lints/src/methods/open_options.rs
index 9b5f138295c31..37a8e25bef96a 100644
--- a/src/tools/clippy/clippy_lints/src/methods/open_options.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/open_options.rs
@@ -18,7 +18,7 @@ fn is_open_options(cx: &LateContext<'_>, ty: Ty<'_>) -> bool {
 
 pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>, recv: &'tcx Expr<'_>) {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(e.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && is_open_options(cx, cx.tcx.type_of(impl_id).instantiate_identity())
     {
         let mut options = Vec::new();
@@ -111,7 +111,7 @@ fn get_open_options(
                     // This might be a user defined extension trait with a method like `truncate_write`
                     // which would be a false positive
                     if let Some(method_def_id) = cx.typeck_results().type_dependent_def_id(argument.hir_id)
-                        && cx.tcx.trait_of_item(method_def_id).is_some()
+                        && cx.tcx.trait_of_assoc(method_def_id).is_some()
                     {
                         return false;
                     }
diff --git a/src/tools/clippy/clippy_lints/src/methods/path_buf_push_overwrite.rs b/src/tools/clippy/clippy_lints/src/methods/path_buf_push_overwrite.rs
index 38d9c5f16778e..32752ef7435fb 100644
--- a/src/tools/clippy/clippy_lints/src/methods/path_buf_push_overwrite.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/path_buf_push_overwrite.rs
@@ -11,7 +11,7 @@ use super::PATH_BUF_PUSH_OVERWRITE;
 
 pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>, arg: &'tcx Expr<'_>) {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id).instantiate_identity(), sym::PathBuf)
         && let ExprKind::Lit(lit) = arg.kind
         && let LitKind::Str(ref path_lit, _) = lit.node
diff --git a/src/tools/clippy/clippy_lints/src/methods/stable_sort_primitive.rs b/src/tools/clippy/clippy_lints/src/methods/stable_sort_primitive.rs
index aef14435d8af3..17d1a6abde0a8 100644
--- a/src/tools/clippy/clippy_lints/src/methods/stable_sort_primitive.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/stable_sort_primitive.rs
@@ -9,7 +9,7 @@ use super::STABLE_SORT_PRIMITIVE;
 
 pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, e: &'tcx Expr<'_>, recv: &'tcx Expr<'_>) {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(e.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && cx.tcx.type_of(impl_id).instantiate_identity().is_slice()
         && let Some(slice_type) = is_slice_of_primitives(cx, recv)
     {
diff --git a/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs b/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
index 6f78d6c612815..51dd4ac313a6d 100644
--- a/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/str_splitn.rs
@@ -286,7 +286,7 @@ fn parse_iter_usage<'tcx>(
             let iter_id = cx.tcx.get_diagnostic_item(sym::Iterator)?;
 
             match (name.ident.name, args) {
-                (sym::next, []) if cx.tcx.trait_of_item(did) == Some(iter_id) => (IterUsageKind::Nth(0), e.span),
+                (sym::next, []) if cx.tcx.trait_of_assoc(did) == Some(iter_id) => (IterUsageKind::Nth(0), e.span),
                 (sym::next_tuple, []) => {
                     return if paths::ITERTOOLS_NEXT_TUPLE.matches(cx, did)
                         && let ty::Adt(adt_def, subs) = cx.typeck_results().expr_ty(e).kind()
@@ -303,7 +303,7 @@ fn parse_iter_usage<'tcx>(
                         None
                     };
                 },
-                (sym::nth | sym::skip, [idx_expr]) if cx.tcx.trait_of_item(did) == Some(iter_id) => {
+                (sym::nth | sym::skip, [idx_expr]) if cx.tcx.trait_of_assoc(did) == Some(iter_id) => {
                     if let Some(Constant::Int(idx)) = ConstEvalCtxt::new(cx).eval(idx_expr) {
                         let span = if name.ident.as_str() == "nth" {
                             e.span
@@ -312,7 +312,7 @@ fn parse_iter_usage<'tcx>(
                             && next_name.ident.name == sym::next
                             && next_expr.span.ctxt() == ctxt
                             && let Some(next_id) = cx.typeck_results().type_dependent_def_id(next_expr.hir_id)
-                            && cx.tcx.trait_of_item(next_id) == Some(iter_id)
+                            && cx.tcx.trait_of_assoc(next_id) == Some(iter_id)
                         {
                             next_expr.span
                         } else {
diff --git a/src/tools/clippy/clippy_lints/src/methods/suspicious_splitn.rs b/src/tools/clippy/clippy_lints/src/methods/suspicious_splitn.rs
index f8b6d4349fbeb..9876681ddbb3a 100644
--- a/src/tools/clippy/clippy_lints/src/methods/suspicious_splitn.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/suspicious_splitn.rs
@@ -10,7 +10,7 @@ use super::SUSPICIOUS_SPLITN;
 pub(super) fn check(cx: &LateContext<'_>, method_name: Symbol, expr: &Expr<'_>, self_arg: &Expr<'_>, count: u128) {
     if count <= 1
         && let Some(call_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(call_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(call_id)
         && cx.tcx.impl_trait_ref(impl_id).is_none()
         && let self_ty = cx.tcx.type_of(impl_id).instantiate_identity()
         && (self_ty.is_slice() || self_ty.is_str())
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_fallible_conversions.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_fallible_conversions.rs
index ce81282ddfeb0..0ec2d8b4fc312 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_fallible_conversions.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_fallible_conversions.rs
@@ -165,7 +165,7 @@ pub(super) fn check_method(cx: &LateContext<'_>, expr: &Expr<'_>) {
 pub(super) fn check_function(cx: &LateContext<'_>, expr: &Expr<'_>, callee: &Expr<'_>) {
     if let ExprKind::Path(ref qpath) = callee.kind
         && let Some(item_def_id) = cx.qpath_res(qpath, callee.hir_id).opt_def_id()
-        && let Some(trait_def_id) = cx.tcx.trait_of_item(item_def_id)
+        && let Some(trait_def_id) = cx.tcx.trait_of_assoc(item_def_id)
     {
         let qpath_spans = match qpath {
             QPath::Resolved(_, path) => {
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_sort_by.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_sort_by.rs
index dbff08bc51c90..1de9f6ab4970f 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_sort_by.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_sort_by.rs
@@ -114,7 +114,7 @@ fn mirrored_exprs(a_expr: &Expr<'_>, a_ident: &Ident, b_expr: &Expr<'_>, b_ident
 
 fn detect_lint(cx: &LateContext<'_>, expr: &Expr<'_>, recv: &Expr<'_>, arg: &Expr<'_>) -> Option<LintTrigger> {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && cx.tcx.type_of(impl_id).instantiate_identity().is_slice()
         && let ExprKind::Closure(&Closure { body, .. }) = arg.kind
         && let closure_body = cx.tcx.hir_body(body)
diff --git a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
index 769526d131bf7..54f45263275ce 100644
--- a/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/unnecessary_to_owned.rs
@@ -694,7 +694,7 @@ fn check_if_applicable_to_argument<'tcx>(cx: &LateContext<'tcx>, arg: &Expr<'tcx
             sym::to_string => cx.tcx.is_diagnostic_item(sym::to_string_method, method_def_id),
             sym::to_vec => cx
                 .tcx
-                .impl_of_method(method_def_id)
+                .impl_of_assoc(method_def_id)
                 .filter(|&impl_did| cx.tcx.type_of(impl_did).instantiate_identity().is_slice())
                 .is_some(),
             _ => false,
@@ -734,7 +734,7 @@ fn check_if_applicable_to_argument<'tcx>(cx: &LateContext<'tcx>, arg: &Expr<'tcx
 fn check_borrow_predicate<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'tcx>) {
     if let ExprKind::MethodCall(_, caller, &[arg], _) = expr.kind
         && let Some(method_def_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && cx.tcx.trait_of_item(method_def_id).is_none()
+        && cx.tcx.trait_of_assoc(method_def_id).is_none()
         && let Some(borrow_id) = cx.tcx.get_diagnostic_item(sym::Borrow)
         && cx.tcx.predicates_of(method_def_id).predicates.iter().any(|(pred, _)| {
             if let ClauseKind::Trait(trait_pred) = pred.kind().skip_binder()
diff --git a/src/tools/clippy/clippy_lints/src/methods/useless_asref.rs b/src/tools/clippy/clippy_lints/src/methods/useless_asref.rs
index d30c12e0c4830..38fad239f6799 100644
--- a/src/tools/clippy/clippy_lints/src/methods/useless_asref.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/useless_asref.rs
@@ -79,7 +79,7 @@ pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, call_name: Symbo
                 applicability,
             );
         }
-    } else if let Some(impl_id) = cx.tcx.impl_of_method(def_id)
+    } else if let Some(impl_id) = cx.tcx.impl_of_assoc(def_id)
         && let Some(adt) = cx.tcx.type_of(impl_id).instantiate_identity().ty_adt_def()
         && matches!(cx.tcx.get_diagnostic_name(adt.did()), Some(sym::Option | sym::Result))
     {
@@ -131,7 +131,7 @@ fn is_calling_clone(cx: &LateContext<'_>, arg: &hir::Expr<'_>) -> bool {
                 hir::ExprKind::MethodCall(method, obj, [], _) => {
                     if method.ident.name == sym::clone
                         && let Some(fn_id) = cx.typeck_results().type_dependent_def_id(closure_expr.hir_id)
-                        && let Some(trait_id) = cx.tcx.trait_of_item(fn_id)
+                        && let Some(trait_id) = cx.tcx.trait_of_assoc(fn_id)
                         // We check it's the `Clone` trait.
                         && cx.tcx.lang_items().clone_trait().is_some_and(|id| id == trait_id)
                         // no autoderefs
diff --git a/src/tools/clippy/clippy_lints/src/methods/vec_resize_to_zero.rs b/src/tools/clippy/clippy_lints/src/methods/vec_resize_to_zero.rs
index 5ea4ada128a24..bfb481f4fc092 100644
--- a/src/tools/clippy/clippy_lints/src/methods/vec_resize_to_zero.rs
+++ b/src/tools/clippy/clippy_lints/src/methods/vec_resize_to_zero.rs
@@ -18,7 +18,7 @@ pub(super) fn check<'tcx>(
     name_span: Span,
 ) {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-        && let Some(impl_id) = cx.tcx.impl_of_method(method_id)
+        && let Some(impl_id) = cx.tcx.impl_of_assoc(method_id)
         && is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id).instantiate_identity(), sym::Vec)
         && let ExprKind::Lit(Spanned {
             node: LitKind::Int(Pu128(0), _),
diff --git a/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs b/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs
index 9b2cfd91b8535..22ec4fe60fb02 100644
--- a/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs
+++ b/src/tools/clippy/clippy_lints/src/operators/cmp_owned.rs
@@ -41,7 +41,7 @@ fn check_op(cx: &LateContext<'_>, expr: &Expr<'_>, other: &Expr<'_>, left: bool)
         ExprKind::MethodCall(_, arg, [], _)
             if typeck
                 .type_dependent_def_id(expr.hir_id)
-                .and_then(|id| cx.tcx.trait_of_item(id))
+                .and_then(|id| cx.tcx.trait_of_assoc(id))
                 .is_some_and(|id| matches!(cx.tcx.get_diagnostic_name(id), Some(sym::ToString | sym::ToOwned))) =>
         {
             (arg, arg.span)
diff --git a/src/tools/clippy/clippy_lints/src/operators/op_ref.rs b/src/tools/clippy/clippy_lints/src/operators/op_ref.rs
index 21e1ab0f4f27d..0a1f2625f4cfc 100644
--- a/src/tools/clippy/clippy_lints/src/operators/op_ref.rs
+++ b/src/tools/clippy/clippy_lints/src/operators/op_ref.rs
@@ -179,7 +179,7 @@ fn in_impl<'tcx>(
     bin_op: DefId,
 ) -> Option<(&'tcx rustc_hir::Ty<'tcx>, &'tcx rustc_hir::Ty<'tcx>)> {
     if let Some(block) = get_enclosing_block(cx, e.hir_id)
-        && let Some(impl_def_id) = cx.tcx.impl_of_method(block.hir_id.owner.to_def_id())
+        && let Some(impl_def_id) = cx.tcx.impl_of_assoc(block.hir_id.owner.to_def_id())
         && let item = cx.tcx.hir_expect_item(impl_def_id.expect_local())
         && let ItemKind::Impl(item) = &item.kind
         && let Some(of_trait) = &item.of_trait
diff --git a/src/tools/clippy/clippy_lints/src/ranges.rs b/src/tools/clippy/clippy_lints/src/ranges.rs
index 9281678b3d837..03d00ba849f3c 100644
--- a/src/tools/clippy/clippy_lints/src/ranges.rs
+++ b/src/tools/clippy/clippy_lints/src/ranges.rs
@@ -380,7 +380,7 @@ fn can_switch_ranges<'tcx>(
     if let ExprKind::MethodCall(_, receiver, _, _) = parent_expr.kind
         && receiver.hir_id == use_ctxt.child_id
         && let Some(method_did) = cx.typeck_results().type_dependent_def_id(parent_expr.hir_id)
-        && let Some(trait_did) = cx.tcx.trait_of_item(method_did)
+        && let Some(trait_did) = cx.tcx.trait_of_assoc(method_did)
         && matches!(
             cx.tcx.get_diagnostic_name(trait_did),
             Some(sym::Iterator | sym::IntoIterator | sym::RangeBounds)
diff --git a/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs b/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs
index 25929b853af86..3497216d1c56e 100644
--- a/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs
+++ b/src/tools/clippy/clippy_lints/src/return_self_not_must_use.rs
@@ -113,7 +113,7 @@ impl<'tcx> LateLintPass<'tcx> for ReturnSelfNotMustUse {
     ) {
         if matches!(kind, FnKind::Method(_, _))
             // We are only interested in methods, not in functions or associated functions.
-            && let Some(impl_def) = cx.tcx.impl_of_method(fn_def.to_def_id())
+            && let Some(impl_def) = cx.tcx.impl_of_assoc(fn_def.to_def_id())
             // We don't want this method to be te implementation of a trait because the
             // `#[must_use]` should be put on the trait definition directly.
             && cx.tcx.trait_id_of_impl(impl_def).is_none()
diff --git a/src/tools/clippy/clippy_lints/src/unconditional_recursion.rs b/src/tools/clippy/clippy_lints/src/unconditional_recursion.rs
index d321c48f6aff8..dcddff557d1c7 100644
--- a/src/tools/clippy/clippy_lints/src/unconditional_recursion.rs
+++ b/src/tools/clippy/clippy_lints/src/unconditional_recursion.rs
@@ -206,7 +206,7 @@ fn check_partial_eq(cx: &LateContext<'_>, method_span: Span, method_def_id: Loca
                 let arg_ty = cx.typeck_results().expr_ty_adjusted(arg);
 
                 if let Some(fn_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-                    && let Some(trait_id) = cx.tcx.trait_of_item(fn_id)
+                    && let Some(trait_id) = cx.tcx.trait_of_assoc(fn_id)
                     && trait_id == trait_def_id
                     && matches_ty(receiver_ty, arg_ty, self_arg, other_arg)
                 {
@@ -250,7 +250,7 @@ fn check_to_string(cx: &LateContext<'_>, method_span: Span, method_def_id: Local
         let is_bad = match expr.kind {
             ExprKind::MethodCall(segment, _receiver, &[_arg], _) if segment.ident.name == name.name => {
                 if let Some(fn_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id)
-                    && let Some(trait_id) = cx.tcx.trait_of_item(fn_id)
+                    && let Some(trait_id) = cx.tcx.trait_of_assoc(fn_id)
                     && trait_id == trait_def_id
                 {
                     true
@@ -318,7 +318,7 @@ where
             && let ExprKind::Path(qpath) = f.kind
             && is_default_method_on_current_ty(self.cx.tcx, qpath, self.implemented_ty_id)
             && let Some(method_def_id) = path_def_id(self.cx, f)
-            && let Some(trait_def_id) = self.cx.tcx.trait_of_item(method_def_id)
+            && let Some(trait_def_id) = self.cx.tcx.trait_of_assoc(method_def_id)
             && self.cx.tcx.is_diagnostic_item(sym::Default, trait_def_id)
         {
             span_error(self.cx, self.method_span, expr);
@@ -426,7 +426,7 @@ fn check_from(cx: &LateContext<'_>, method_span: Span, method_def_id: LocalDefId
     if let Some((fn_def_id, node_args)) = fn_def_id_with_node_args(cx, expr)
         && let [s1, s2] = **node_args
         && let (Some(s1), Some(s2)) = (s1.as_type(), s2.as_type())
-        && let Some(trait_def_id) = cx.tcx.trait_of_item(fn_def_id)
+        && let Some(trait_def_id) = cx.tcx.trait_of_assoc(fn_def_id)
         && cx.tcx.is_diagnostic_item(sym::Into, trait_def_id)
         && get_impl_trait_def_id(cx, method_def_id) == cx.tcx.get_diagnostic_item(sym::From)
         && s1 == sig.inputs()[0]
diff --git a/src/tools/clippy/clippy_lints/src/unused_io_amount.rs b/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
index 12cc109389939..f3cd3f1bb286f 100644
--- a/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
+++ b/src/tools/clippy/clippy_lints/src/unused_io_amount.rs
@@ -84,7 +84,7 @@ impl<'tcx> LateLintPass<'tcx> for UnusedIoAmount {
     /// get desugared to match.
     fn check_block(&mut self, cx: &LateContext<'tcx>, block: &'tcx hir::Block<'tcx>) {
         let fn_def_id = block.hir_id.owner.to_def_id();
-        if let Some(impl_id) = cx.tcx.impl_of_method(fn_def_id)
+        if let Some(impl_id) = cx.tcx.impl_of_assoc(fn_def_id)
             && let Some(trait_id) = cx.tcx.trait_id_of_impl(impl_id)
         {
             // We don't want to lint inside io::Read or io::Write implementations, as the author has more
@@ -300,7 +300,7 @@ fn check_io_mode(cx: &LateContext<'_>, call: &hir::Expr<'_>) -> Option<IoOp> {
     };
 
     if let Some(method_def_id) = cx.typeck_results().type_dependent_def_id(call.hir_id)
-        && let Some(trait_def_id) = cx.tcx.trait_of_item(method_def_id)
+        && let Some(trait_def_id) = cx.tcx.trait_of_assoc(method_def_id)
     {
         if let Some(diag_name) = cx.tcx.get_diagnostic_name(trait_def_id) {
             match diag_name {
diff --git a/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs b/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs
index 9d38672efada9..eb3f442ac754b 100644
--- a/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs
+++ b/src/tools/clippy/clippy_utils/src/eager_or_lazy.rs
@@ -51,7 +51,7 @@ impl ops::BitOrAssign for EagernessSuggestion {
 fn fn_eagerness(cx: &LateContext<'_>, fn_id: DefId, name: Symbol, have_one_arg: bool) -> EagernessSuggestion {
     use EagernessSuggestion::{Eager, Lazy, NoChange};
 
-    let ty = match cx.tcx.impl_of_method(fn_id) {
+    let ty = match cx.tcx.impl_of_assoc(fn_id) {
         Some(id) => cx.tcx.type_of(id).instantiate_identity(),
         None => return Lazy,
     };
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
index ce5af4d2f482e..67e09e772a772 100644
--- a/src/tools/clippy/clippy_utils/src/lib.rs
+++ b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -349,7 +349,7 @@ pub fn is_ty_alias(qpath: &QPath<'_>) -> bool {
 /// Checks if the given method call expression calls an inherent method.
 pub fn is_inherent_method_call(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
     if let Some(method_id) = cx.typeck_results().type_dependent_def_id(expr.hir_id) {
-        cx.tcx.trait_of_item(method_id).is_none()
+        cx.tcx.trait_of_assoc(method_id).is_none()
     } else {
         false
     }
@@ -357,7 +357,7 @@ pub fn is_inherent_method_call(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
 
 /// Checks if a method is defined in an impl of a diagnostic item
 pub fn is_diag_item_method(cx: &LateContext<'_>, def_id: DefId, diag_item: Symbol) -> bool {
-    if let Some(impl_did) = cx.tcx.impl_of_method(def_id)
+    if let Some(impl_did) = cx.tcx.impl_of_assoc(def_id)
         && let Some(adt) = cx.tcx.type_of(impl_did).instantiate_identity().ty_adt_def()
     {
         return cx.tcx.is_diagnostic_item(diag_item, adt.did());
@@ -367,7 +367,7 @@ pub fn is_diag_item_method(cx: &LateContext<'_>, def_id: DefId, diag_item: Symbo
 
 /// Checks if a method is in a diagnostic item trait
 pub fn is_diag_trait_item(cx: &LateContext<'_>, def_id: DefId, diag_item: Symbol) -> bool {
-    if let Some(trait_did) = cx.tcx.trait_of_item(def_id) {
+    if let Some(trait_did) = cx.tcx.trait_of_assoc(def_id) {
         return cx.tcx.is_diagnostic_item(diag_item, trait_did);
     }
     false
@@ -620,7 +620,7 @@ fn is_default_equivalent_ctor(cx: &LateContext<'_>, def_id: DefId, path: &QPath<
 
     if let QPath::TypeRelative(_, method) = path
         && method.ident.name == sym::new
-        && let Some(impl_did) = cx.tcx.impl_of_method(def_id)
+        && let Some(impl_did) = cx.tcx.impl_of_assoc(def_id)
         && let Some(adt) = cx.tcx.type_of(impl_did).instantiate_identity().ty_adt_def()
     {
         return std_types_symbols.iter().any(|&symbol| {
diff --git a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
index b3356450d387a..11c17a77b1542 100644
--- a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
+++ b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
@@ -420,7 +420,7 @@ pub fn is_stable_const_fn(cx: &LateContext<'_>, def_id: DefId, msrv: Msrv) -> bo
             .lookup_const_stability(def_id)
             .or_else(|| {
                 cx.tcx
-                    .trait_of_item(def_id)
+                    .trait_of_assoc(def_id)
                     .and_then(|trait_def_id| cx.tcx.lookup_const_stability(trait_def_id))
             })
             .is_none_or(|const_stab| {