Auto merge of #11802 - dswij:issue-11765, r=xFrednet

`needless_return_with_question_mark` ignore let-else

Fixes #11765

This PR makes `needless_return_with_question_mark` to ignore expr inside let-else.

changelog: [`needless_return_with_question_mark`] ignore let-else

clippy_utils/src/lib.rs

@@ -1487,6 +1487,43 @@ pub fn is_else_clause(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
     }
 }
 
+/// Checks if the given expression is a part of `let else`
+/// returns `true` for both the `init` and the `else` part
+pub fn is_inside_let_else(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
+    let mut child_id = expr.hir_id;
+    for (parent_id, node) in tcx.hir().parent_iter(child_id) {
+        if let Node::Local(Local {
+            init: Some(init),
+            els: Some(els),
+            ..
+        }) = node
+            && (init.hir_id == child_id || els.hir_id == child_id)
+        {
+            return true;
+        }
+
+        child_id = parent_id;
+    }
+
+    false
+}
+
+/// Checks if the given expression is the else clause of a `let else` expression
+pub fn is_else_clause_in_let_else(tcx: TyCtxt<'_>, expr: &Expr<'_>) -> bool {
+    let mut child_id = expr.hir_id;
+    for (parent_id, node) in tcx.hir().parent_iter(child_id) {
+        if let Node::Local(Local { els: Some(els), .. }) = node
+            && els.hir_id == child_id
+        {
+            return true;
+        }
+
+        child_id = parent_id;
+    }
+
+    false
+}
+
 /// Checks whether the given `Expr` is a range equivalent to a `RangeFull`.
 /// For the lower bound, this means that:
 /// - either there is none