Fix out of order tables dict-like behavior (python-poetry#79)

tests/test_toml_document.py

@@ -535,3 +535,21 @@ def test_values_can_still_be_set_for_out_of_order_tables():
 
     with pytest.raises(NonExistentKey):
         del doc["a"]["a"]["key"]
+
+
+def test_out_of_order_tables_are_still_dicts():
+    content = """
+[a.a]
+key = "value"
+
+[a.b]
+
+[a.a.c]
+"""
+
+    doc = parse(content)
+    assert isinstance(doc["a"], dict)
+    assert isinstance(doc["a"]["a"], dict)
+
+    assert "key" in doc["a"]["a"]
+    assert "c" in doc["a"]["a"]

tomlkit/container.py

@@ -638,7 +638,7 @@ def __copy__(self):  # type: () -> Container
         return c
 
 
-class OutOfOrderTableProxy(object):
+class OutOfOrderTableProxy(dict):
     def __init__(self, container, indices):  # type: (Container, Tuple) -> None
         self._container = container
         self._internal_container = Container(self._container.parsing)
@@ -692,6 +692,15 @@ def __delitem__(self, key):  # type: (Union[Key, str]) -> None
 
         del self._internal_container[key]
 
+    def keys(self):
+        return self._internal_container.keys()
+
+    def values(self):
+        return self._internal_container.values()
+
+    def __contains__(self, key):
+        return key in self._internal_container
+
     def __str__(self):
         return str(self._internal_container)