From ab30dab081c4e004812eab00a36c70e5b8e4e29b Mon Sep 17 00:00:00 2001
From: md-work <>
Date: Thu, 14 Dec 2017 11:37:18 +0100
Subject: [PATCH 4/5] Wrapping &blocks only when there is a Func check. (bug
 278)

---
 lib/contracts/call_with.rb | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/contracts/call_with.rb b/lib/contracts/call_with.rb
index c9336a1..9252c79 100644
--- a/lib/contracts/call_with.rb
+++ b/lib/contracts/call_with.rb
@@ -81,8 +81,10 @@ module Contracts
                  method.call(*args, &blk)
                else
                  # original method name reference
-                 added_block = blk ? lambda { |*params| blk.call(*params) } : nil
-                 method.send_to(this, *args, &added_block)
+                 # Don't reassign blk, else Travis CI shows "stack level too deep".
+                 target_blk = blk
+                 target_blk = lambda { |*params| blk.call(*params) } if blk && blk.is_a?(Contract)
+                 method.send_to(this, *args, &target_blk)
                end
 
       unless @ret_validator[result]
-- 
2.29.2