replace HashSet with FxHashSet

Author: y21

clippy_lints/src/missing_fields_in_debug.rs

@@ -1,11 +1,12 @@
-use std::{collections::HashSet, ops::ControlFlow};
+use std::ops::ControlFlow;
 
 use clippy_utils::{
     diagnostics::span_lint_and_then,
     match_def_path, paths,
     visitors::{for_each_expr, Visitable},
 };
 use if_chain::if_chain;
+use rustc_data_structures::fx::FxHashSet;
 use rustc_hir::{
     def::{DefKind, Res},
     ImplItemKind, MatchSource, Node,
@@ -14,6 +15,7 @@ use rustc_hir::{Block, PatKind};
 use rustc_hir::{ExprKind, Impl, ItemKind, QPath, TyKind};
 use rustc_hir::{ImplItem, Item, VariantData};
 use rustc_lint::{LateContext, LateLintPass};
+use rustc_middle::ty::Ty;
 use rustc_middle::ty::TypeckResults;
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::{sym, Span};
@@ -143,11 +145,11 @@ fn check_struct<'tcx>(
     cx: &LateContext<'tcx>,
     typeck_results: &TypeckResults<'tcx>,
     block: &'tcx Block<'tcx>,
-    self_ty: rustc_middle::ty::Ty<'tcx>,
+    self_ty: Ty<'tcx>,
     item: &'tcx Item<'tcx>,
     data: &VariantData<'_>,
 ) {
-    let mut field_accesses = HashSet::new();
+    let mut field_accesses = FxHashSet::default();
 
     let _: Option<!> = for_each_expr(block, |expr| {
         if_chain! {
@@ -188,7 +190,7 @@ fn check_enum<'tcx>(
     cx: &LateContext<'tcx>,
     typeck_results: &TypeckResults<'tcx>,
     block: &'tcx Block<'tcx>,
-    self_ty: rustc_middle::ty::Ty<'tcx>,
+    self_ty: Ty<'tcx>,
     item: &'tcx Item<'tcx>,
 ) {
     let Some(arms) = for_each_expr(block, |expr| {
@@ -222,7 +224,7 @@ fn check_enum<'tcx>(
             _ => {},
         });
 
-        let mut field_accesses = HashSet::new();
+        let mut field_accesses = FxHashSet::default();
 
         let _: Option<!> = for_each_expr(arm.body, |expr| {
             if_chain! {