diff -r 058bb3dc685f -r 0b59724cb3f2 cubicweb/test/unittest_binary.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cubicweb/test/unittest_binary.py	Sat Jan 16 13:48:51 2016 +0100
@@ -0,0 +1,54 @@
+from six import PY2
+
+from unittest import TestCase
+from tempfile import NamedTemporaryFile
+import os.path as osp
+
+from logilab.common.shellutils import tempdir
+from cubicweb import Binary
+
+
+class BinaryTC(TestCase):
+    def test_init(self):
+        Binary()
+        Binary(b'toto')
+        Binary(bytearray(b'toto'))
+        if PY2:
+            Binary(buffer('toto'))
+        else:
+            Binary(memoryview(b'toto'))
+        with self.assertRaises((AssertionError, TypeError)):
+            # TypeError is raised by BytesIO if python runs with -O
+            Binary(u'toto')
+
+    def test_write(self):
+        b = Binary()
+        b.write(b'toto')
+        b.write(bytearray(b'toto'))
+        if PY2:
+            b.write(buffer('toto'))
+        else:
+            b.write(memoryview(b'toto'))
+        with self.assertRaises((AssertionError, TypeError)):
+            # TypeError is raised by BytesIO if python runs with -O
+            b.write(u'toto')
+
+    def test_gzpickle_roundtrip(self):
+        old = (u'foo', b'bar', 42, {})
+        new = Binary.zpickle(old).unzpickle()
+        self.assertEqual(old, new)
+        self.assertIsNot(old, new)
+
+    def test_from_file_to_file(self):
+        with tempdir() as dpath:
+            fpath = osp.join(dpath, 'binary.bin')
+            with open(fpath, 'wb') as fobj:
+                Binary(b'binaryblob').to_file(fobj)
+
+            bobj = Binary.from_file(fpath)
+            self.assertEqual(bobj.getvalue(), b'binaryblob')
+
+
+if __name__ == '__main__':
+    from unittest import main
+    main()