packb supports use_single_float option.

ChangeLog.rst

@@ -1,6 +1,11 @@
 0.2.2
 =======
-:release date: NOT RELEASED YET
+:release date: 2012-09-21
+
+Changes
+-------
+* Add ``use_single_float`` option to ``Packer``. When it is true, packs float
+  object in single precision format.
 
 Bugs fixed
 -----------
@@ -8,6 +13,8 @@ Bugs fixed
   ``unpack()`` doesn't control gc now instead of restoring gc state collectly.
   User can control gc state when gc cause performance issue.
 
+* ``Unpacker``'s ``read_size`` option didn't used.
+
 0.2.1
 =======
 :release date: 2012-08-20

msgpack/_msgpack.pyx

@@ -177,10 +177,11 @@ def pack(object o, object stream, default=None, encoding='utf-8', unicode_errors
     packer = Packer(default=default, encoding=encoding, unicode_errors=unicode_errors)
     stream.write(packer.pack(o))
 
-def packb(object o, default=None, encoding='utf-8', unicode_errors='strict'):
+def packb(object o, default=None, encoding='utf-8', unicode_errors='strict', use_single_float=False):
     """
     pack o and return packed bytes."""
-    packer = Packer(default=default, encoding=encoding, unicode_errors=unicode_errors)
+    packer = Packer(default=default, encoding=encoding, unicode_errors=unicode_errors,
+                    use_single_float=use_single_float)
     return packer.pack(o)
 
 

test/test_pack.py

@@ -2,6 +2,7 @@
 # coding: utf-8
 
 import six
+import struct
 from nose import main
 from nose.tools import *
 from nose.plugins.skip import SkipTest
@@ -86,5 +87,9 @@ def testDecodeBinary():
     re = unpackb(packb("abc"), encoding=None)
     assert_equal(re, b"abc")
 
+def testPackFloat():
+    assert_equal(packb(1.0, use_single_float=True),  b'\xca' + struct.pack('>f', 1.0))
+    assert_equal(packb(1.0, use_single_float=False), b'\xcb' + struct.pack('>d', 1.0))
+
 if __name__ == '__main__':
     main()