any way to detect this cycle?

[Mike Bayer]

also why does it happen with append_whereclause, but not where?

from sqlalchemy import *
from sqlalchemy.sql import table, column

t = table('t', column('x'))

s = select([t](t))

s = s.append_whereclause(s.c.x > 5)

print s

[Mike Bayer]

eh? maybe

diff --git a/lib/sqlalchemy/sql/selectable.py b/lib/sqlalchemy/sql/selectable.py
index e06262c..3ee0bfb 100644
--- a/lib/sqlalchemy/sql/selectable.py
+++ b/lib/sqlalchemy/sql/selectable.py
@@ -1936,6 +1936,8 @@ class Select(HasPrefixes, SelectBase):

         def add(items):
             for item in items:
+                if item is self:
+                    raise exc.InvalidRequestError("boom")
                 if translate and item in translate:
                     item = translate[item](item)
                 if not seen.intersection(item._cloned_set):

[Mike Bayer]

that really only catches exactly this mistake and nothing else, but im not sure what other variants of this mistake there are.

[Mike Bayer]

e488bb47e4bd21ff0a09ce23e1adf00ba64d5d57 0.8

e74627f827542044c1d2087be95e41d4b1b46f24 master

[Mike Bayer]

Removing milestone: 0.8.xx (automated comment)