Fix a crash when _filter_stmts encounters an EmptyNode (#1534)

ChangeLog

@@ -14,6 +14,10 @@ Release date: TBA
 
 * Fix ``col_offset`` attribute for nodes involving ``with`` on ``PyPy``.
 
+* Fixed a crash when ``_filter_stmts`` encounters an ``EmptyNode``.
+
+  Closes PyCQA/pylint#6438
+
 
 What's New in astroid 2.11.3?
 =============================

astroid/filter_statements.py

@@ -112,15 +112,15 @@ def _filter_stmts(base_node: nodes.NodeNG, stmts, frame, offset):
         # Fixes issue #375
         if mystmt is stmt and _is_from_decorator(base_node):
             continue
-        assert hasattr(node, "assign_type"), (
-            node,
-            node.scope(),
-            node.scope().locals,
-        )
-        assign_type = node.assign_type()
         if node.has_base(base_node):
             break
 
+        if isinstance(node, nodes.EmptyNode):
+            # EmptyNode does not have assign_type(), so just add it and move on
+            _stmts.append(node)
+            continue
+
+        assign_type = node.assign_type()
         _stmts, done = assign_type._get_filtered_stmts(base_node, node, _stmts, mystmt)
         if done:
             break

tests/unittest_filter_statements.py

@@ -0,0 +1,17 @@
+# Licensed under the LGPL: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.en.html
+# For details: https://github.com/PyCQA/astroid/blob/main/LICENSE
+# Copyright (c) https://github.com/PyCQA/astroid/blob/main/CONTRIBUTORS.txt
+
+from astroid.builder import extract_node
+from astroid.filter_statements import _filter_stmts
+from astroid.nodes import EmptyNode
+
+
+def test_empty_node() -> None:
+    enum_mod = extract_node("import enum")
+    empty = EmptyNode(parent=enum_mod)
+    empty.is_statement = True
+    filtered_statements = _filter_stmts(
+        empty, [empty.statement(future=True)], empty.frame(future=True), 0
+    )
+    assert filtered_statements[0] is empty