[ModuleMap] Add spec for private headers

lib/cocoapods/generator/module_map.rb

@@ -56,7 +56,7 @@ module Pod
 
       def generate_private_header_exports
         private_headers.reduce('') do |string, header|
-          string << %(  private header "#{header}\n")
+          string << %(  private header "#{header}"\n)
         end
       end
     end

spec/unit/generator/module_map_spec.rb

@@ -21,5 +21,19 @@ module Pod
         }
       EOS
     end
+
+    it 'correctly adds private headers' do
+      @gen.stubs(:private_headers).returns(['Private.h'])
+      @gen.generate.should == <<-EOS.strip_heredoc
+        framework module BananaLib {
+          umbrella header "Pods-default-BananaLib-umbrella.h"
+
+          export *
+          module * { export * }
+
+          private header "Private.h"
+        }
+      EOS
+    end
   end
 end