Make sure we do not mutate the buffer and from-byte-buffer is idempot…

…ent. Mutable data structures, FUUUUUUUU
clojurewerkz · Jul 13, 2012 · 04aa6b6 · 04aa6b6
1 parent f249d54
commit 04aa6b6
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Showing 2 changed files with 9 additions and 4 deletions.
diff --git a/src/clojure/clojurewerkz/support/string.clj b/src/clojure/clojurewerkz/support/string.clj
@@ -125,5 +125,7 @@
   "Creates a new string from the contents of the provided NIO byte buffer"
   [^java.nio.ByteBuffer buf]
   (let [ary (byte-array (.remaining buf))]
+    (.mark buf)
     (.get buf ary)
+    (.reset buf)
     (String. ^bytes ary)))
diff --git a/test/clojurewerkz/support/string_test.clj b/test/clojurewerkz/support/string_test.clj
@@ -101,7 +101,10 @@
 
 
 (deftest test-from-byte-buffer
-  (let [s   "a string"
-        buf (java.nio.ByteBuffer/wrap (.getBytes s "UTF-8"))
-        res (s/from-byte-buffer buf)]
-    (is (= s res))))
+  (let [s    "a string"
+        buf  (java.nio.ByteBuffer/wrap (.getBytes s "UTF-8"))
+        ;; buffers are mutable, make sure the function is idempotent
+        res1 (s/from-byte-buffer buf)
+        res2 (s/from-byte-buffer buf)
+        res3 (s/from-byte-buffer buf)]
+    (is (= s res1 res2 res3))))