Fix from_dict() silently truncating dict keys that contain dots

pyhocon/config_parser.py

@@ -167,7 +167,10 @@ def create_tree(value):
             if isinstance(value, dict):
                 res = ConfigTree(root=root)
                 for key, child_value in value.items():
-                    res.put(key, create_tree(child_value))
+                    # Use _put with a single-element path to preserve the literal key.
+                    # Using put() would split the key on dots (e.g. "a.b" → path ["a","b"]),
+                    # truncating or nesting keys that contain HOCON path-separator characters.
+                    res._put([key], create_tree(child_value))
                 return res
             if isinstance(value, list):
                 return [create_tree(v) for v in value]

pyhocon/config_tree.py

@@ -227,6 +227,16 @@ def get(self, key, default=UndefinedKey):
         :type default: object
         :return: value in the tree located at key
         """
+        # Try an exact (literal) key lookup first so that keys containing dots
+        # that were stored verbatim (e.g. via from_dict()) are found before the
+        # dotted-path traversal interprets those dots as path separators.
+        exact = super(ConfigTree, self).get(key, UndefinedKey)
+        if exact is not UndefinedKey:
+            if isinstance(exact, NoneValue):
+                return None
+            if isinstance(exact, list):
+                return [None if isinstance(x, NoneValue) else x for x in exact]
+            return exact
         return self._get(ConfigTree.parse_key(key), 0, default)
 
     def get_string(self, key, default=UndefinedKey):

tests/test_config_parser.py

@@ -2310,6 +2310,24 @@ def test_from_dict_with_nested_dict(self):
         config = ConfigFactory.from_dict(d)
         assert config == d
 
+    def test_from_dict_preserves_dotted_keys(self):
+        """Keys containing dots must be stored as literal keys, not split into nested paths."""
+        d = {
+            'myStuff': {
+                'myThing_r0.1': ['someVal'],
+            }
+        }
+        config = ConfigFactory.from_dict(d)
+        # The key 'myThing_r0.1' must appear verbatim, not be truncated to 'myThing_r0'.
+        assert list(config['myStuff'].keys()) == ['myThing_r0.1']
+        # Iterating items() must also yield the original key.
+        items = list(config['myStuff'].items())
+        assert items == [('myThing_r0.1', ['someVal'])]
+        # Direct get() must find the value.
+        assert config['myStuff'].get('myThing_r0.1') == ['someVal']
+        # Round-trip equality with the original dict.
+        assert config == d
+
     def test_object_concat(self):
         config = ConfigFactory.parse_string(
             """o1 = {