Quick workaround for #1969.

peewee.py

@@ -460,6 +460,9 @@ class DatabaseProxy(Proxy):
         return _savepoint(self)
 
 
+class ModelDescriptor(object): pass
+
+
 # SQL Generation.
 
 
@@ -6423,6 +6426,18 @@ class ModelAlias(Node):
         self.__dict__['alias'] = alias
 
     def __getattr__(self, attr):
+        # Hack to work-around the fact that properties or other objects
+        # implementing the descriptor protocol (on the model being aliased),
+        # will not work correctly when we use getattr(). So we explicitly pass
+        # the model alias to the descriptor's getter.
+        try:
+            obj = self.model.__dict__[attr]
+        except KeyError:
+            pass
+        else:
+            if isinstance(obj, ModelDescriptor):
+                return obj.__get__(None, self)
+
         model_attr = getattr(self.model, attr)
         if isinstance(model_attr, Field):
             self.__dict__[attr] = FieldAlias.create(self, model_attr)

playhouse/hybrid.py

@@ -1,6 +1,9 @@
+from peewee import ModelDescriptor
+
+
 # Hybrid methods/attributes, based on similar functionality in SQLAlchemy:
 # http://docs.sqlalchemy.org/en/improve_toc/orm/extensions/hybrid.html
-class hybrid_method(object):
+class hybrid_method(ModelDescriptor):
     def __init__(self, func, expr=None):
         self.func = func
         self.expr = expr or func
@@ -15,7 +18,7 @@ class hybrid_method(object):
         return self
 
 
-class hybrid_property(object):
+class hybrid_property(ModelDescriptor):
     def __init__(self, fget, fset=None, fdel=None, expr=None):
         self.fget = fget
         self.fset = fset

tests/hybrid.py

@@ -99,3 +99,12 @@ class TestHybridProperties(ModelTestCase):
         query = Person.select().where(Person.full_name.startswith('huey c'))
         huey_db = query.get()
         self.assertEqual(huey_db.id, huey.id)
+
+    def test_hybrid_model_alias(self):
+        Person.create(first='huey', last='cat')
+        PA = Person.alias()
+        query = PA.select(PA.full_name).where(PA.last == 'cat')
+        self.assertSQL(query, (
+            'SELECT (("t1"."first" || ?) || "t1"."last") '
+            'FROM "person" AS "t1" WHERE ("t1"."last" = ?)'), [' ', 'cat'])
+        self.assertEqual(query.tuples()[0], ('huey cat',))