From 3864490a02a9e9c4350af420eb30847df90f28b7 Mon Sep 17 00:00:00 2001
From: Oleksii Fedorov <waterlink000@gmail.com>
Date: Wed, 9 Sep 2015 16:53:48 +0200
Subject: [PATCH 1/2] [fixes #176] Do not redefine 'Contract' in class_eval for
 'extend' to work

---
 lib/contracts/core.rb  |  6 +++++-
 spec/contracts_spec.rb | 29 +++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/lib/contracts/core.rb b/lib/contracts/core.rb
index 89f6e3e..14b207c 100644
--- a/lib/contracts/core.rb
+++ b/lib/contracts/core.rb
@@ -28,7 +28,11 @@ def functype(funcname)
         # TODO: deprecate
         # Required when contracts are included in global scope
         def Contract(*args)
-          self.class.Contract(*args)
+          if defined?(super)
+            super
+          else
+            self.class.Contract(*args)
+          end
         end
 
         def functype(funcname)
diff --git a/spec/contracts_spec.rb b/spec/contracts_spec.rb
index 31e2df8..b7f1bc4 100644
--- a/spec/contracts_spec.rb
+++ b/spec/contracts_spec.rb
@@ -717,4 +717,33 @@ def delim(match)
       expect { c.double("asd") }.to raise_error
     end
   end
+
+  describe "classes with extended modules" do
+    let(:klass) do
+      m = Module.new do
+        include Contracts::Core
+      end
+
+      Class.new do
+        include Contracts::Core
+        extend m
+
+        Contract String => nil
+        def foo(x)
+        end
+      end
+    end
+
+    it "is possible to define it" do
+      expect { klass }.not_to raise_error
+    end
+
+    it "works correctly with methods with passing contracts" do
+      expect { klass.new.foo("bar") }.not_to raise_error
+    end
+
+    it "works correctly with methods with passing contracts" do
+      expect { klass.new.foo(42) }.to raise_error(ContractError, /Expected: String/)
+    end
+  end
 end

From e637c44035078e25825a514e9fb4a8b4bf21663b Mon Sep 17 00:00:00 2001
From: Oleksii Fedorov <waterlink000@gmail.com>
Date: Wed, 9 Sep 2015 23:59:43 +0200
Subject: [PATCH 2/2] Fix defined?(super) for ruby 1.9.2

---
 lib/contracts/core.rb | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/contracts/core.rb b/lib/contracts/core.rb
index 14b207c..fdbb517 100644
--- a/lib/contracts/core.rb
+++ b/lib/contracts/core.rb
@@ -24,7 +24,10 @@ def functype(funcname)
         end
       end
 
-      base.class_eval do
+      # NOTE: Workaround for `defined?(super)` bug in ruby 1.9.2
+      # source: http://stackoverflow.com/a/11181685
+      # bug: https://bugs.ruby-lang.org/issues/6644
+      base.class_eval <<-RUBY
         # TODO: deprecate
         # Required when contracts are included in global scope
         def Contract(*args)
@@ -34,7 +37,9 @@ def Contract(*args)
             self.class.Contract(*args)
           end
         end
+      RUBY
 
+      base.class_eval do
         def functype(funcname)
           contracts = Engine.fetch_from(self.class).decorated_methods_for(:instance_methods, funcname)
           if contracts.nil?