Rollup merge of #113567 - chenyukang:yukang-fix-113354-while-let, r=cjgillot

While let suggestion will work for closure body

Fixes #113354

compiler/rustc_infer/src/infer/error_reporting/suggest.rs

@@ -464,11 +464,8 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
         span: Span,
     ) -> Option<TypeErrorAdditionalDiags> {
         let hir = self.tcx.hir();
-        if let Some(node) = self.tcx.hir().find_by_def_id(cause.body_id) &&
+        if let Some(body_id) = self.tcx.hir().maybe_body_owned_by(cause.body_id) {
-            let hir::Node::Item(hir::Item {
+            let body = hir.body(body_id);
-                    kind: hir::ItemKind::Fn(_sig, _, body_id), ..
-                }) = node {
-        let body = hir.body(*body_id);
 
             /// Find the if expression with given span
             struct IfVisitor {
@@ -479,7 +476,9 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
 
             impl<'v> Visitor<'v> for IfVisitor {
                 fn visit_expr(&mut self, ex: &'v hir::Expr<'v>) {
-                if self.result { return; }
+                    if self.result {
+                        return;
+                    }
                     match ex.kind {
                         hir::ExprKind::If(cond, _, _) => {
                             self.found_if = true;
@@ -509,7 +508,9 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             let mut visitor = IfVisitor { err_span: span, found_if: false, result: false };
             visitor.visit_body(&body);
             if visitor.result {
-                return Some(TypeErrorAdditionalDiags::AddLetForLetChains{span: span.shrink_to_lo()});
+                return Some(TypeErrorAdditionalDiags::AddLetForLetChains {
+                    span: span.shrink_to_lo(),
+                });
             }
         }
         None

tests/ui/inference/issue-113354.fixed

@@ -0,0 +1,4 @@
+//run-rustfix
+fn main() {
+    let _ = || { while let Some(_) = Some(1) { } }; //~ ERROR mismatched types
+}

tests/ui/inference/issue-113354.rs

@@ -0,0 +1,4 @@
+//run-rustfix
+fn main() {
+    let _ = || { while Some(_) = Some(1) { } }; //~ ERROR mismatched types
+}

tests/ui/inference/issue-113354.stderr

@@ -0,0 +1,14 @@
+error[E0308]: mismatched types
+  --> $DIR/issue-113354.rs:3:24
+   |
+LL |     let _ = || { while Some(_) = Some(1) { } };
+   |                        ^^^^^^^^^^^^^^^^^ expected `bool`, found `()`
+   |
+help: consider adding `let`
+   |
+LL |     let _ = || { while let Some(_) = Some(1) { } };
+   |                        +++
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0308`.