fix: base64 spec

spec/amber/controller/render_spec.cr

@@ -30,9 +30,9 @@ module Amber::Controller
       end
 
       it "renders a form with a csrf tag" do
-        reuslt = RenderController.new(context).render_with_csrf
-        reuslt.should contain "<form"
-        reuslt.should contain "<input type=\"hidden\" name=\"_csrf\" value="
+        result = RenderController.new(context).render_with_csrf
+        result.should contain "<form"
+        result.should contain "<input type=\"hidden\" name=\"_csrf\" value="
       end
     end
   end

src/amber/pipes/csrf.cr

@@ -43,7 +43,10 @@ module Amber
         end
 
         def real_session_token(context) : String
-          (context.session[CSRF_KEY] ||= Random::Secure.urlsafe_base64(TOKEN_LENGTH)).to_s
+          unless context.session[CSRF_KEY].is_a? String
+            context.session[CSRF_KEY] = Random::Secure.urlsafe_base64(TOKEN_LENGTH)
+          end
+          context.session[CSRF_KEY].as(String)
         end
       end