question_mark: Ignore ifs with else branches

Author: sinkuu

clippy_lints/src/question_mark.rs

@@ -64,7 +64,7 @@ impl Pass {
     /// If it matches, it will suggest to use the question mark operator instead
     fn check_is_none_and_early_return_none(cx: &LateContext<'_, '_>, expr: &Expr) {
         if_chain! {
-            if let ExprKind::If(ref if_expr, ref body, _) = expr.node;
+            if let ExprKind::If(ref if_expr, ref body, None) = expr.node;
             if let ExprKind::MethodCall(ref segment, _, ref args) = if_expr.node;
             if segment.ident.name == "is_none";
             if Self::expression_returns_none(cx, body);

tests/ui/question_mark.rs

@@ -47,6 +47,13 @@ impl SomeStruct {
             return None;
         }
 
+        // OK if `else` branch exists.
+        let _ = if (self.opt).is_none() {
+            return None;
+        } else {
+            self.opt
+        };
+
         self.opt
     }
 }