[deprecation/fix] rollback to old class_deprecation being a class behavior

It breaks CW because CW was using class_deprecated in a isinstance to select
the good views to uses.

1 files changed, 32 insertions, 13 deletions

diff --git a/logilab/common/deprecation.py b/logilab/common/deprecation.py
index 47f2895..af23f07 100644
--- a/logilab/common/deprecation.py
+++ b/logilab/common/deprecation.py
@@ -215,23 +215,28 @@ def callable_deprecated(reason=None, version=None, stacklevel=2):
 deprecated = callable_renamed(old_name="deprecated", new_function=callable_deprecated)
 
 
-def class_deprecated(old_name, parent, class_dict):
-    class DeprecatedClass(*parent):
-        def __init__(self, *args, **kwargs):
-            msg = class_dict.get("__deprecation_warning__", f"{old_name} is deprecated")
+def _generate_class_deprecated():
+    class _class_deprecated(type):
+        """metaclass to print a warning on instantiation of a deprecated class"""
+
+        def __call__(cls, *args, **kwargs):
+            message = getattr(cls, "__deprecation_warning__", "%(cls)s is deprecated") % {
+                "cls": cls.__name__
+            }
             send_warning(
-                msg,
-                stacklevel=class_dict.get("__deprecation_warning_stacklevel__", 3),
-                version=class_dict.get("__deprecation_warning_version__", None),
-                module_name=class_dict.get(
-                    "__deprecation_warning_module_name__", _get_module_name(1)
+                message,
+                module_name=getattr(
+                    cls, "__deprecation_warning_module_name__", _get_module_name(1)
                 ),
+                stacklevel=getattr(cls, "__deprecation_warning_stacklevel__", 4),
+                version=getattr(cls, "__deprecation_warning_version__", None),
             )
-            super(DeprecatedClass, self).__init__(*args, **kwargs)
+            return type.__call__(cls, *args, **kwargs)
 
-    DeprecatedClass.__name__ = old_name
+    return _class_deprecated
 
-    return DeprecatedClass
+
+class_deprecated = _generate_class_deprecated()
 
 
 def attribute_renamed(old_name, new_name, version=None):
@@ -378,7 +383,21 @@ def class_renamed(old_name, new_class, message=None, version=None, module_name=N
     else:
         class_dict["__deprecation_warning_module_name__"] = _get_module_name(1)
 
-    return class_deprecated(old_name, (new_class,), class_dict)
+    try:
+        return class_deprecated(old_name, (new_class,), class_dict)
+    except (NameError, TypeError):
+        # in case of conflicting metaclass situation
+        class DeprecatedClass(new_class):
+            def __init__(self, *args, **kwargs):
+                msg = class_dict.get("__deprecation_warning__", f"{old_name} is deprecated")
+                send_warning(
+                    msg,
+                    stacklevel=class_dict.get("__deprecation_warning_stacklevel__", 3),
+                    version=class_dict.get("__deprecation_warning_version__", None),
+                )
+                super(DeprecatedClass, self).__init__(*args, **kwargs)
+
+        return DeprecatedClass
 
 
 def class_moved(new_class, old_name=None, message=None, version=None):