Fix false positive for the unnecessary-ellipsis checker (#6039)

When an ellipsis is used in a lambda expression.

  Closes #6036

Co-authored-by: Mark Byrne <mark.byrne@rabobank.com>
Co-authored-by: Pierre Sassoulas <pierre.sassoulas@gmail.com>

ChangeLog

@@ -24,8 +24,9 @@ Release date: TBA
 
   Closes #6028
 
-* Fix crash for ``unneccessary-ellipsis`` checker when an ellipsis is used inside of a container.
+* Fix crash for ``unneccessary-ellipsis`` checker when an ellipsis is used inside of a container or a lambda expression.
 
+  Closes #6036
   Closes #6037
   Closes #6048
 

pylint/checkers/ellipsis_checker.py

@@ -49,6 +49,7 @@ def visit_const(self, node: nodes.Const) -> None:
                     nodes.Assign,
                     nodes.BaseContainer,
                     nodes.Call,
+                    nodes.Lambda,
                 ),
             )
             and (

tests/functional/u/unnecessary/unnecessary_ellipsis.py

@@ -102,7 +102,6 @@ def __getitem__(self, index: Union[int, slice]) -> Union[int, List[int]]:
 def func_with_ellipsis_default_arg(a = ...) -> None:
     "Some docstring."
 
-
 # Ignore if the ellipsis is inside a container:
 my_list = [...]
 my_tuple = (...,)
@@ -112,3 +111,6 @@ def func_with_ellipsis_default_arg(a = ...) -> None:
 mydict1 = {'x': [...]}
 mydict2 = {'x': {...}}
 mydict3 = {'x': (...,)}
+
+# Ignore if the ellipsis is used with a lambda expression
+print("x", lambda: ...)