Do not trigger let_and_return on let else (#16829)

changelog: [`let_and_return_on`]: do not trigger on `let else` construct

Fixes rust-lang/rust-clippy#16820

Author: samueltardieu

clippy_lints/src/returns/let_and_return.rs

@@ -19,6 +19,7 @@ pub(super) fn check_block<'tcx>(cx: &LateContext<'tcx>, block: &'tcx Block<'_>)
         && let Some(stmt) = block.stmts.last()
         && let StmtKind::Let(local) = &stmt.kind
         && local.ty.is_none()
+        && local.els.is_none()
         && cx.tcx.hir_attrs(local.hir_id).is_empty()
         && let Some(initexpr) = &local.init
         && let PatKind::Binding(_, local_id, _, _) = local.pat.kind

tests/ui/let_and_return.edition2021.fixed

@@ -292,4 +292,14 @@ fn wrongly_unmangled_macros() -> i32 {
     //~^ let_and_return
 }
 
+fn issue16820() -> Option<i32> {
+    let value = Some(42);
+
+    let v @ None = value else {
+        panic!("uh oh!");
+    };
+
+    v
+}
+
 fn main() {}

tests/ui/let_and_return.edition2024.fixed

@@ -292,4 +292,14 @@ fn wrongly_unmangled_macros() -> i32 {
     //~^ let_and_return
 }
 
+fn issue16820() -> Option<i32> {
+    let value = Some(42);
+
+    let v @ None = value else {
+        panic!("uh oh!");
+    };
+
+    v
+}
+
 fn main() {}

tests/ui/let_and_return.rs

@@ -292,4 +292,14 @@ fn wrongly_unmangled_macros() -> i32 {
     //~^ let_and_return
 }
 
+fn issue16820() -> Option<i32> {
+    let value = Some(42);
+
+    let v @ None = value else {
+        panic!("uh oh!");
+    };
+
+    v
+}
+
 fn main() {}