Fix root key loss

Closes #51

flatten_json/__init__.py

@@ -335,7 +335,9 @@ def _unflatten(dic, keys, value):
  list_keys = sorted(flat_dict.keys())
  for i, item in enumerate(list_keys):
  if i != len(list_keys) - 1:
- if not list_keys[i + 1].startswith(list_keys[i]):
+ split_key = item.split(separator)
+ next_split_key = list_keys[i + 1].split(separator)
+ if not split_key == next_split_key[:-1]:
  _unflatten(unflattened_dict, item.split(separator),
  flat_dict[item])
  else:

test_flatten.py

@@ -267,6 +267,22 @@ def test_unflatten_with_df_issue40(self):
  actual = unflatten(dic, '.')
  self.assertEqual(actual, expected)
 
+ def test_unflatten_with_key_loss_issue51(self):
+ """https://github.com/amirziai/flatten/issues/51"""
+ dic = {
+ 'a': 1,
+ 'a_b': 2,
+ 'a_c.d': 3,
+ 'a_c.e': 4
+ }
+ expected = {
+ 'a': 1,
+ 'a_b': 2,
+ 'a_c': {'d': 3, 'e': 4}
+ }
+ actual = unflatten(dic, '.')
+ self.assertEqual(actual, expected)
+
  def test_flatten_preserve_lists_issue43_nested(self):
  """https://github.com/amirziai/flatten/issues/43"""
  dic = {