fix: fix double subscriptable error (docarray#1800)

Joan Fontanals · web-flow · commit 7209b7849a2f · 2023-09-27T17:45:55.000+02:00
Signed-off-by: Joan Fontanals Martinez &lt;joan.martinez@jina.ai&gt;
Signed-off-by: Joan Fontanals &lt;joan.martinez@jina.ai&gt;
diff --git a/docarray/array/doc_list/doc_list.py b/docarray/array/doc_list/doc_list.py
@@ -335,6 +335,8 @@ def __getitem__(self, item):
 
     @classmethod
     def __class_getitem__(cls, item: Union[Type[BaseDocWithoutId], TypeVar, str]):
+        if cls.doc_type != AnyDoc:
+            raise TypeError(f'{cls} object is not subscriptable')
 
         if isinstance(item, type) and safe_issubclass(item, BaseDocWithoutId):
             return AnyDocArray.__class_getitem__.__func__(cls, item)  # type: ignore
diff --git a/tests/units/array/test_array.py b/tests/units/array/test_array.py
@@ -467,7 +467,6 @@ class Image(BaseDoc):
 
 
 def test_validate_list_dict():
-
     images = [
         dict(url=f'http://url.com/foo_{i}.png', tensor=NdArray(i)) for i in [2, 0, 1]
     ]
@@ -493,7 +492,18 @@ def test_parameterize_list():
     from docarray import DocList, BaseDoc
 
     with pytest.raises(TypeError) as excinfo:
-        doc = DocList[BaseDoc()]
-        assert doc is None
+        da = DocList[BaseDoc()]
+        assert da is None
 
     assert str(excinfo.value) == 'Expecting a type, got object instead'
+
+
+def test_not_double_subcriptable():
+    from docarray import DocList
+    from docarray.documents import TextDoc
+
+    with pytest.raises(TypeError) as excinfo:
+        da = DocList[TextDoc][TextDoc]
+        assert da is None
+
+    assert 'not subscriptable' in str(excinfo.value)
