Fix safe_encode(): return bytes on Python 3

safe_decode() decodes bytes to text. safe_encode() should be the reverse
operation: encode text to bytes. Currently, it returns text on Python 3
which is wrong in my opinion.

The patch fixes also test_encode() on Python 3.

Change-Id: If91a866d864a22d28a352152beff4c7406a27b7b

2 files changed, 17 insertions, 20 deletions

diff --git a/openstack/common/strutils.py b/openstack/common/strutils.py
index e7a0b17..29cd572 100644
--- a/openstack/common/strutils.py
+++ b/openstack/common/strutils.py
@@ -159,19 +159,13 @@ def safe_encode(text, incoming=None,
                     sys.getdefaultencoding())
 
     if isinstance(text, six.text_type):
-        if six.PY3:
-            return text.encode(encoding, errors).decode(incoming)
-        else:
-            return text.encode(encoding, errors)
+        return text.encode(encoding, errors)
     elif text and encoding != incoming:
         # Decode text before encoding it with `encoding`
         text = safe_decode(text, incoming, errors)
-        if six.PY3:
-            return text.encode(encoding, errors).decode(incoming)
-        else:
-            return text.encode(encoding, errors)
-
-    return text
+        return text.encode(encoding, errors)
+    else:
+        return text
 
 
 def string_to_bytes(text, unit_system='IEC', return_int=False):
diff --git a/tests/unit/test_strutils.py b/tests/unit/test_strutils.py
index a4ad73a..6f3adb7 100644
--- a/tests/unit/test_strutils.py
+++ b/tests/unit/test_strutils.py
@@ -166,18 +166,21 @@ class StrUtilsTest(test.BaseTestCase):
     def test_safe_encode(self):
         safe_encode = strutils.safe_encode
         self.assertRaises(TypeError, safe_encode, True)
-        self.assertEqual("ni\xc3\xb1o", safe_encode(six.u('ni\xf1o'),
-                                                    encoding="utf-8"))
-        self.assertEqual("dGVzdA==\n", safe_encode("test",
-                                                   encoding='base64'))
-        self.assertEqual('ni\xf1o', safe_encode("ni\xc3\xb1o",
-                                                encoding="iso-8859-1",
-                                                incoming="utf-8"))
+        self.assertEqual(six.b("ni\xc3\xb1o"), safe_encode(six.u('ni\xf1o'),
+                                                           encoding="utf-8"))
+        if six.PY2:
+            # In Python 3, str.encode() doesn't support anymore
+            # text => text encodings like base64
+            self.assertEqual(six.b("dGVzdA==\n"),
+                             safe_encode("test", encoding='base64'))
+        self.assertEqual(six.b('ni\xf1o'), safe_encode(six.b("ni\xc3\xb1o"),
+                                                       encoding="iso-8859-1",
+                                                       incoming="utf-8"))
 
         # Forcing incoming to ascii so it falls back to utf-8
-        self.assertEqual('ni\xc3\xb1o', safe_encode('ni\xc3\xb1o',
-                                                    incoming='ascii'))
-        self.assertEqual('foo', safe_encode(b'foo'))
+        self.assertEqual(six.b('ni\xc3\xb1o'),
+                         safe_encode(six.b('ni\xc3\xb1o'), incoming='ascii'))
+        self.assertEqual(six.b('foo'), safe_encode(six.u('foo')))
 
     def test_slugify(self):
         to_slug = strutils.to_slug