diff --git a/src/expr.rs b/src/expr.rs
index 99208b921340..7cebf793c600 100644
--- a/src/expr.rs
+++ b/src/expr.rs
@@ -2281,10 +2281,10 @@ fn rewrite_last_closure(
         let body_shape = try_opt!(shape.offset_left(extra_offset));
         // When overflowing the closure which consists of a single control flow expression,
         // force to use block if its condition uses multi line.
-        if rewrite_cond(context, body, body_shape)
-            .map(|cond| cond.contains('\n'))
-            .unwrap_or(false)
-        {
+        let is_multi_lined_cond = rewrite_cond(context, body, body_shape)
+            .map(|cond| cond.contains('\n') || cond.len() > body_shape.width)
+            .unwrap_or(false);
+        if is_multi_lined_cond {
             return rewrite_closure_with_block(context, body_shape, &prefix, body);
         }