If the block takes an argument, don't modify the scope.

Author: ioquatix

lib/protocol/http/middleware/builder.rb

@@ -30,7 +30,13 @@ def to_app
 			def self.build(&block)
 				builder = Builder.new
 
-				builder.instance_eval(&block)
+				if block_given?
+					if block.arity == 0
+						builder.instance_exec(&block)
+					else
+						yield builder
+					end
+				end
 
 				return builder.to_app
 			end

test/protocol/http/middleware/builder.rb

@@ -29,4 +29,16 @@
 
 		expect(app).to be_a(Protocol::HTTP::Middleware)
 	end
+	
+	it "provides the builder as an argument" do
+		current_self = self
+		
+		app = Protocol::HTTP::Middleware.build do |builder|
+			builder.use Protocol::HTTP::Middleware
+			
+			expect(self).to be_equal(current_self)
+		end
+		
+		expect(app).to be_a(Protocol::HTTP::Middleware)
+	end
 end