@@ -37,6 +37,7 @@ def attrinfo(basename, base, attrname):
 
 endpython
 """
+from __future__ import annotations
 
 
 class VimErrorMock(Exception):
@@ -61,7 +62,7 @@ class BufferMock(ub.NiceRepr):
         'range', 'valid', 'vars']
     """
     def __init__(self, text=None):
-        self._lines = None
+        self._lines: list[str] | None = None
         self.name = ''
 
         self.number = 1
@@ -102,29 +103,29 @@ def mark(self, key):
 
     @property
     def _text(self):
-        return '\n'.join(self._lines)
+        return '\n'.join(self._lines)  # type: ignore
 
     def __delitem__(self, key):
-        del self._lines[key]
+        del self._lines[key]  # type: ignore
 
     def __getitem__(self, key):
         # Note indexing into a buffer is zero indexed like normal
         # However remember reported cursor positions are 1 indexed
         if isinstance(key, slice):
-            return self._lines[key.start : key.stop : key.step]
+            return self._lines[key.start : key.stop : key.step]  # type: ignore
         if not isinstance(key, int):
             raise TypeError("Index should be integer, not %s" % classname(key))
-        return self._lines[key]
+        return self._lines[key]  # type: ignore
 
     def __setitem__(self, key, value):
         if isinstance(key, slice):
-            self._lines[key.start : key.stop : key.step] = value
+            self._lines[key.start : key.stop : key.step] = value  # type: ignore
         elif not isinstance(key, int):
             raise TypeError("Indes should be integer, not %s" % classname(key))
-        self._lines[key] = value
+        self._lines[key] = value  # type: ignore
 
     def __len__(self):
-        return len(self._lines)
+        return len(self._lines)  # type: ignore
 
     def setup_text(self, text=None, name=''):
         text = text or ''