Enforce top level keys check in `merge` method. #367

benedict/dicts/__init__.py

@@ -26,6 +26,7 @@ from benedict.dicts.io import IODict
 from benedict.dicts.keyattr import KeyattrDict
 from benedict.dicts.keylist import KeylistDict
 from benedict.dicts.keypath import KeypathDict
+from benedict.dicts.keypath import keypath_util
 from benedict.dicts.parse import ParseDict
 from benedict.serializers import JSONSerializer, YAMLSerializer
 
@@ -219,7 +220,10 @@ class benedict(KeyattrDict, KeypathDict, IODict, ParseDict):
         If overwrite is False, existing values will not be overwritten.
         If concat is True, list values will be concatenated together.
         """
-        _merge(self, other, *args, **kwargs)
+        others = [other] + list(args)
+        for other in others:
+            keypath_util.check_keys(other, self._keypath_separator)
+        _merge(self, *others, **kwargs)
 
     def move(self, key_src, key_dest):
         """

tests/github/test_issue_0367.py

@@ -0,0 +1,33 @@
+import unittest
+
+from benedict import benedict
+
+
+class github_issue_0367_test_case(unittest.TestCase):
+    """
+    This class describes a github issue 0367 test case.
+    https://github.com/fabiocaccamo/python-benedict/issues/367
+
+    To run this specific test:
+    - Run python -m unittest tests.github.test_issue_0367
+    """
+
+    def test_dict_keys_with_separators_with_merge(self):
+        d = {"foo.bar": 1}
+        b = benedict()
+        with self.assertRaises(ValueError):
+            b.merge(d)
+        # self.assertEqual(b, {"foo": {"bar": 1}})
+
+    def test_dict_keys_with_separators_with_nested_merge(self):
+        d = {"baz": {"foo.bar": 1}}
+        b = benedict()
+        with self.assertRaises(ValueError):
+            b.merge(d)
+        # self.assertEqual(b, {"baz": {"foo.bar": 1}})
+
+    def test_dict_keys_with_separators_with_constructor(self):
+        d = {"foo.bar": 1}
+        with self.assertRaises(ValueError):
+            benedict(d)
+        # self.assertEqual(b, {"foo": {"bar": 1}})