Add :default cases to multi-methods (closes weavejester#1)

src/resauce/core.clj

@@ -38,6 +38,9 @@
         entry (.getEntry jar (add-ending-slash path))]
     (and entry (.isDirectory entry))))
 
+(defmethod directory? :default [url]
+  false)
+
 (defmulti url-dir
   "Return a list of URLs contained by this URL, if the protocol supports it."
   {:arglists '([url])}
@@ -56,6 +59,9 @@
          (filter-dir-paths path)
          (map (partial build-url url path)))))
 
+(defmethod url-dir nil [url]
+  nil)
+
 (defn- default-loader []
   (.getContextClassLoader (Thread/currentThread)))
 

test/resauce/core_test.clj

@@ -7,7 +7,8 @@
   (is (directory? (io/resource "resauce")))
   (is (directory? (io/resource "clojure")))
   (is (not (directory? (io/resource "resauce/core.clj"))))
-  (is (not (directory? (io/resource "clojure/core.clj")))))
+  (is (not (directory? (io/resource "clojure/core.clj"))))
+  (is (not (directory? nil))))
 
 (deftest test-resources
   (let [rs (sort (map str (resources "resauce")))]
@@ -16,6 +17,8 @@
     (is (re-find #"test/resauce$" (second rs)))))
 
 (deftest test-url-dir
+  (is (nil? (url-dir nil)))
+  (is (thrown? java.lang.IllegalArgumentException (url-dir (io/as-url "http://www.example.com/docs/resource1.html"))))
   (testing "file URL"
     (let [rs (url-dir (io/as-url (io/file "src/resauce")))]
       (is (= (count rs) 1))