Better error reporting on invalid cookie attributes

@@ -88,8 +88,9 @@
 
 (defn- valid-attr?
   "Is the attribute valid?"
-  [[_ value]]
-  (not (.contains (str value) ";")))
+  [[key value]]
+  (and (contains? set-cookie-attrs key)
+       (not (.contains (str value) ";"))))
 
 (defn- write-attr-map
   "Write a map of cookie attributes to a string."
@@ -118,7 +119,7 @@
     (update-in response
                [:headers "Set-Cookie"]
                concat
-               (write-cookies cookies))
+               (doall (write-cookies cookies)))
     response))
 
 (defn wrap-cookies

@@ -78,3 +78,8 @@
         resp    ((wrap-cookies handler) {})]
     (is (= {"Set-Cookie" (list "a=b" "c=d")}
            (:headers resp)))))
+
+(deftest wrap-cookies-invalid-attrs
+  (let [response {:cookies {"a" {:value "foo" :invalid true}}}
+        handler  (wrap-cookies (constantly response))]
+    (is (thrown? AssertionError (handler {})))))