fixed #4646 : distutils was choking on empty options arg in the setup function.

dist.py

@@ -235,7 +235,7 @@ Common commands: (see '--help-commands' for more)
             # command options will override any supplied redundantly
             # through the general options dictionary.
             options = attrs.get('options')
-            if options:
+            if options is not None:
                 del attrs['options']
                 for (command, cmd_options) in options.items():
                     opt_dict = self.get_option_dict(command)

tests/test_dist.py

@@ -8,6 +8,7 @@ import os
 import StringIO
 import sys
 import unittest
+import warnings
 
 from test.test_support import TESTFN
 
@@ -131,6 +132,29 @@ class DistributionTestCase(unittest.TestCase):
             if os.path.exists(my_file):
                 os.remove(my_file)
 
+    def test_empty_options(self):
+        # an empty options dictionary should not stay in the
+        # list of attributes
+        klass = distutils.dist.Distribution
+
+        # catching warnings
+        warns = []
+        def _warn(msg):
+            warns.append(msg)
+
+        old_warn = warnings.warn
+        warnings.warn = _warn
+        try:
+            dist = klass(attrs={'author': 'xxx',
+                                'name': 'xxx',
+                                'version': 'xxx',
+                                'url': 'xxxx',
+                                'options': {}})
+        finally:
+            warnings.warn = old_warn
+
+        self.assertEquals(len(warns), 0)
+
 class MetadataTestCase(unittest.TestCase):
 
     def test_simple_metadata(self):