Auto merge of #9082 - Alexendoo:let_unit_allow, r=xFrednet

Fix direct `#[allow]` attributes in `let_unit_value`

Fixes part of #9080

Not sure why it doesn't work when the lint is emitted at the statement, but switching it to the local works fine

changelog: Fix direct `#[allow]` attributes in [`let_unit_value`]

2 files changed, 11 insertions, 12 deletions

diff --git a/clippy_lints/src/unit_types/let_unit_value.rs b/clippy_lints/src/unit_types/let_unit_value.rs
index 27678c8ba3c..17d60a40dce 100644
--- a/clippy_lints/src/unit_types/let_unit_value.rs
+++ b/clippy_lints/src/unit_types/let_unit_value.rs
@@ -4,18 +4,17 @@ use clippy_utils::visitors::for_each_value_source;
 use core::ops::ControlFlow;
 use rustc_errors::Applicability;
 use rustc_hir::def::{DefKind, Res};
-use rustc_hir::{Expr, ExprKind, PatKind, Stmt, StmtKind};
+use rustc_hir::{Expr, ExprKind, Local, PatKind};
 use rustc_lint::{LateContext, LintContext};
 use rustc_middle::lint::in_external_macro;
 use rustc_middle::ty::{self, Ty, TypeFoldable, TypeSuperFoldable, TypeVisitor};
 
 use super::LET_UNIT_VALUE;
 
-pub(super) fn check(cx: &LateContext<'_>, stmt: &Stmt<'_>) {
-    if let StmtKind::Local(local) = stmt.kind
-        && let Some(init) = local.init
+pub(super) fn check(cx: &LateContext<'_>, local: &Local<'_>) {
+    if let Some(init) = local.init
         && !local.pat.span.from_expansion()
-        && !in_external_macro(cx.sess(), stmt.span)
+        && !in_external_macro(cx.sess(), local.span)
         && cx.typeck_results().pat_ty(local.pat).is_unit()
     {
         let needs_inferred = for_each_value_source(init, &mut |e| if needs_inferred_result_ty(cx, e) {
@@ -29,7 +28,7 @@ pub(super) fn check(cx: &LateContext<'_>, stmt: &Stmt<'_>) {
                 span_lint_and_then(
                     cx,
                     LET_UNIT_VALUE,
-                    stmt.span,
+                    local.span,
                     "this let-binding has unit value",
                     |diag| {
                             diag.span_suggestion(
@@ -45,15 +44,15 @@ pub(super) fn check(cx: &LateContext<'_>, stmt: &Stmt<'_>) {
             span_lint_and_then(
                 cx,
                 LET_UNIT_VALUE,
-                stmt.span,
+                local.span,
                 "this let-binding has unit value",
                 |diag| {
                     if let Some(expr) = &local.init {
                         let snip = snippet_with_macro_callsite(cx, expr.span, "()");
                         diag.span_suggestion(
-                            stmt.span,
+                            local.span,
                             "omit the `let` binding",
-                            format!("{};", snip),
+                            format!("{snip};"),
                             Applicability::MachineApplicable, // snippet
                         );
                     }
diff --git a/clippy_lints/src/unit_types/mod.rs b/clippy_lints/src/unit_types/mod.rs
index a9e2073dec2..e57d4fc3b89 100644
--- a/clippy_lints/src/unit_types/mod.rs
+++ b/clippy_lints/src/unit_types/mod.rs
@@ -3,7 +3,7 @@ mod unit_arg;
 mod unit_cmp;
 mod utils;
 
-use rustc_hir::{Expr, Stmt};
+use rustc_hir::{Expr, Local};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
@@ -99,8 +99,8 @@ declare_clippy_lint! {
 declare_lint_pass!(UnitTypes => [LET_UNIT_VALUE, UNIT_CMP, UNIT_ARG]);
 
 impl LateLintPass<'_> for UnitTypes {
-    fn check_stmt(&mut self, cx: &LateContext<'_>, stmt: &Stmt<'_>) {
-        let_unit_value::check(cx, stmt);
+    fn check_local(&mut self, cx: &LateContext<'_>, local: &Local<'_>) {
+        let_unit_value::check(cx, local);
     }
 
     fn check_expr(&mut self, cx: &LateContext<'_>, expr: &Expr<'_>) {