Add support for tab-completion in VSCode and IPython/Jupyter. #502

Author: fabiocaccamo

benedict/dicts/keyattr/keyattr_dict.py

@@ -68,6 +68,22 @@ def __setattr__(self, attr: _K | str, value: Any) -> None:
                 raise AttributeError(attr_message)
             self.__setitem__(attr_k, value)
 
+    def __dir__(self) -> list[str]:
+        # Extend tab-completion (VSCode, IPython, etc.) with the dict keys when
+        # keyattr is enabled, since keys are accessible as attributes via __getattr__.
+        # Non-string keys are excluded: __dir__ must return strings (Python protocol)
+        # and non-string keys can never be valid attribute names anyway.
+        keys: list[str] = (
+            [key for key in self.keys() if isinstance(key, str)]
+            if self._keyattr_enabled
+            else []
+        )
+        return sorted(set(list(super().__dir__()) + keys))
+
+    def _ipython_key_completions_(self) -> list[Any]:
+        # Used by IPython/Jupyter for subscript tab-completion: obj["<TAB>"]
+        return list(self.keys())
+
     def __setstate__(self, state: Mapping[str, Any]) -> None:
         super().__setstate__(state)
         self._keyattr_enabled = state["_keyattr_enabled"]

tests/dicts/test_benedict_keyattr.py

@@ -216,3 +216,37 @@ def test_keyattr_dynamic_inheritance_on_casting(self) -> None:
         d = benedict(keyattr_dynamic=False)
         c = benedict(d)
         self.assertFalse(c.keyattr_dynamic)
+
+    def test_dir_with_keyattr_enabled(self) -> None:
+        d = benedict({"a": 1, "b": 2}, keyattr_enabled=True)
+        result = dir(d)
+        self.assertIn("a", result)
+        self.assertIn("b", result)
+
+    def test_dir_with_keyattr_disabled(self) -> None:
+        d = benedict({"a": 1, "b": 2}, keyattr_enabled=False)
+        result = dir(d)
+        self.assertNotIn("a", result)
+        self.assertNotIn("b", result)
+
+    def test_dir_with_nested_keys(self) -> None:
+        d = benedict({"a": {"b": {"c": 1}}}, keyattr_enabled=True)
+        self.assertIn("a", dir(d))
+        self.assertIn("b", dir(d.a))
+        self.assertIn("c", dir(d.a.b))
+
+    def test_ipython_key_completions(self) -> None:
+        d = benedict({"a": 1, "b": 2})
+        self.assertEqual(sorted(d._ipython_key_completions_()), ["a", "b"])
+
+    def test_ipython_key_completions_with_nested_keys(self) -> None:
+        d = benedict({"a": {"b": {"c": 1}}})
+        self.assertEqual(d._ipython_key_completions_(), ["a"])
+        self.assertEqual(d.a._ipython_key_completions_(), ["b"])
+        self.assertEqual(d.a.b._ipython_key_completions_(), ["c"])
+
+    def test_dir_skips_non_string_keys(self) -> None:
+        d = benedict({1: "a", "b": 2}, keyattr_enabled=True)
+        result = dir(d)
+        self.assertIn("b", result)
+        self.assertNotIn(1, result)