From 2582e36da3bb1ac57fe0472f6d424da40520dc51 Mon Sep 17 00:00:00 2001
From: Luqman Aden <me@luqman.ca>
Date: Thu, 24 Nov 2022 21:15:46 -0500
Subject: [PATCH] Don't suggest associated function call for associated const.

---
 compiler/rustc_hir_typeck/src/method/probe.rs    | 16 +++++++++++++---
 .../dont-suggest-ufcs-for-const.stderr           |  8 +-------
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/compiler/rustc_hir_typeck/src/method/probe.rs b/compiler/rustc_hir_typeck/src/method/probe.rs
index 44c3edf06a8..979e7e25996 100644
--- a/compiler/rustc_hir_typeck/src/method/probe.rs
+++ b/compiler/rustc_hir_typeck/src/method/probe.rs
@@ -9,7 +9,6 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
 use rustc_hir::def::DefKind;
-use rustc_hir::def::Namespace;
 use rustc_infer::infer::canonical::OriginalQueryValues;
 use rustc_infer::infer::canonical::{Canonical, QueryResponse};
 use rustc_infer::infer::type_variable::{TypeVariableOrigin, TypeVariableOriginKind};
@@ -1881,6 +1880,11 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
     // The length of the returned iterator is nearly always 0 or 1 and this
     // method is fairly hot.
     fn impl_or_trait_item(&self, def_id: DefId) -> SmallVec<[ty::AssocItem; 1]> {
+        let relevant_kind_for_mode = |kind| match (self.mode, kind) {
+            (Mode::MethodCall, ty::AssocKind::Fn) => true,
+            (Mode::Path, ty::AssocKind::Const | ty::AssocKind::Fn) => true,
+            _ => false,
+        };
         if let Some(name) = self.method_name {
             if self.allow_similar_names {
                 let max_dist = max(name.as_str().len(), 3) / 3;
@@ -1888,7 +1892,7 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
                     .associated_items(def_id)
                     .in_definition_order()
                     .filter(|x| {
-                        if x.kind.namespace() != Namespace::ValueNS {
+                        if !relevant_kind_for_mode(x.kind) {
                             return false;
                         }
                         match lev_distance_with_substrings(name.as_str(), x.name.as_str(), max_dist)
@@ -1902,10 +1906,16 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
             } else {
                 self.fcx
                     .associated_value(def_id, name)
+                    .filter(|x| relevant_kind_for_mode(x.kind))
                     .map_or_else(SmallVec::new, |x| SmallVec::from_buf([x]))
             }
         } else {
-            self.tcx.associated_items(def_id).in_definition_order().copied().collect()
+            self.tcx
+                .associated_items(def_id)
+                .in_definition_order()
+                .filter(|x| relevant_kind_for_mode(x.kind))
+                .copied()
+                .collect()
         }
     }
 }
diff --git a/src/test/ui/suggestions/dont-suggest-ufcs-for-const.stderr b/src/test/ui/suggestions/dont-suggest-ufcs-for-const.stderr
index 04e0511d788..0d9543e0b8f 100644
--- a/src/test/ui/suggestions/dont-suggest-ufcs-for-const.stderr
+++ b/src/test/ui/suggestions/dont-suggest-ufcs-for-const.stderr
@@ -2,13 +2,7 @@ error[E0599]: no method named `MAX` found for type `u32` in the current scope
   --> $DIR/dont-suggest-ufcs-for-const.rs:2:11
    |
 LL |     1_u32.MAX();
-   |     ------^^^--
-   |     |     |
-   |     |     this is an associated function, not a method
-   |     help: use associated function syntax instead: `u32::MAX()`
-   |
-   = note: found the following associated functions; to be used as methods, functions must have a `self` parameter
-   = note: the candidate is defined in an impl for the type `u32`
+   |           ^^^ method not found in `u32`
 
 error: aborting due to previous error