clippy: support `QPath::LangItem`

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

diff --git a/clippy_lints/src/temporary_assignment.rs b/clippy_lints/src/temporary_assignment.rs
index 4b0c4abc44e36f2f2aa721c17ff6f15ab414ecb9..1aeff1baa362e24a2362263c07a946e412abde46 100644 (file)
--- a/clippy_lints/src/temporary_assignment.rs
+++ b/clippy_lints/src/temporary_assignment.rs
@@ -1,10 +1,8 @@
-use crate::utils::is_adjusted;
-use crate::utils::span_lint;
-use rustc::declare_lint_pass;
-use rustc::hir::def::{DefKind, Res};
-use rustc::hir::{Expr, ExprKind};
-use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use rustc_session::declare_tool_lint;
+use crate::utils::{is_adjusted, span_lint};
+use rustc_hir::def::{DefKind, Res};
+use rustc_hir::{Expr, ExprKind};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
 
 declare_clippy_lint! {
     /// **What it does:** Checks for construction of a structure or tuple just to
@@ -24,24 +22,18 @@
     "assignments to temporaries"
 }
 
-fn is_temporary(cx: &LateContext<'_, '_>, expr: &Expr) -> bool {
+fn is_temporary(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
     match &expr.kind {
         ExprKind::Struct(..) | ExprKind::Tup(..) => true,
-        ExprKind::Path(qpath) => {
-            if let Res::Def(DefKind::Const, ..) = cx.tables.qpath_res(qpath, expr.hir_id) {
-                true
-            } else {
-                false
-            }
-        },
+        ExprKind::Path(qpath) => matches!(cx.qpath_res(qpath, expr.hir_id), Res::Def(DefKind::Const, ..)),
         _ => false,
     }
 }
 
 declare_lint_pass!(TemporaryAssignment => [TEMPORARY_ASSIGNMENT]);
 
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for TemporaryAssignment {
-    fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
+impl<'tcx> LateLintPass<'tcx> for TemporaryAssignment {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if let ExprKind::Assign(target, ..) = &expr.kind {
             let mut base = target;
             while let ExprKind::Field(f, _) | ExprKind::Index(f, _) = &base.kind {