[fix] AttributeError crash when a slice is used as a class decorator

Closes #10334

Author: Pierre-Sassoulas

doc/whatsnew/fragments/10334.bugfix

@@ -0,0 +1,3 @@
+Using a slice as a class decorator now raise a 'not-callable' message instead of crashing pylint.
+
+Closes #10334

pylint/checkers/deprecated.py

@@ -138,7 +138,7 @@ def visit_decorators(self, node: nodes.Decorators) -> None:
             inferred = safe_infer(children[0])
         if not inferred:
             return
-        qname = inferred.qname()
+        qname = inferred.qname() if hasattr(inferred, "qname") else ""
         if qname in self.deprecated_decorators():
             self.add_message("deprecated-decorator", node=node, args=qname)
 
@@ -217,7 +217,12 @@ def check_deprecated_attribute(self, node: astroid.Attribute) -> None:
         inferred_expr = safe_infer(node.expr)
         if not isinstance(inferred_expr, (nodes.ClassDef, Instance, nodes.Module)):
             return
-        attribute_qname = ".".join((inferred_expr.qname(), node.attrname))
+        attribute_qname = ".".join(
+            (
+                inferred_expr.qname() if hasattr(inferred_expr, "qname") else "",
+                node.attrname,
+            )
+        )
         for deprecated_name in self.deprecated_attributes():
             if attribute_qname == deprecated_name:
                 self.add_message(

pylint/checkers/utils.py

@@ -873,7 +873,8 @@ def decorated_with(
             decorator_node = decorator_node.func
         try:
             if any(
-                i.name in qnames or i.qname() in qnames
+                hasattr(i, "name")
+                and (i.name in qnames or (hasattr(i, "qname") and i.qname() in qnames))
                 for i in decorator_node.infer()
                 if i is not None and not isinstance(i, util.UninferableBase)
             ):

tests/functional/r/regression_02/regression_10334.py

@@ -0,0 +1,6 @@
+"""Test for slice object used as a decorator."""
+# pylint: disable=too-few-public-methods
+s = slice(-2)
+@s()  # [not-callable]
+class A:
+    """Class with a slice decorator."""