Fixed django#12140 -- Fixed http.urlencode result for empty lists

Thanks aneil for the report and the initial patch.

Author: claudep

django/utils/http.py

@@ -71,7 +71,7 @@ def urlencode(query, doseq=0):
  query = query.items()
  return urllib.urlencode(
  [(smart_str(k),
- isinstance(v, (list,tuple)) and [smart_str(i) for i in v] or smart_str(v))
+ [smart_str(i) for i in v] if isinstance(v, (list,tuple)) else smart_str(v))
  for k, v in query],
  doseq)
 

tests/regressiontests/utils/http.py

@@ -31,6 +31,7 @@ def test_urlencode(self):
  # 2-tuples (the norm)
  result = http.urlencode((('a', 1), ('b', 2), ('c', 3)))
  self.assertEqual(result, 'a=1&b=2&c=3')
+
  # A dictionary
  result = http.urlencode({ 'a': 1, 'b': 2, 'c': 3})
  acceptable_results = [
@@ -44,6 +45,13 @@ def test_urlencode(self):
  'c=3&b=2&a=1'
  ]
  self.assertTrue(result in acceptable_results)
+ result = http.urlencode({'a': [1, 2]}, doseq=False)
+ self.assertEqual(result, 'a=%5B%271%27%2C+%272%27%5D')
+ result = http.urlencode({'a': [1, 2]}, doseq=True)
+ self.assertEqual(result, 'a=1&a=2')
+ result = http.urlencode({'a': []}, doseq=True)
+ self.assertEqual(result, '')
+
  # A MultiValueDict
  result = http.urlencode(MultiValueDict({
  'name': ['Adrian', 'Simon'],