How to replicate AssertionError

[rad-pat]

I am receiving an AssertionError in 1.4.7, code works fine in 1.3.24. My attempts to build a minimal repl don't seem to yield the same error so I was wondering what I could gather to help debug this?

Traceback:

Traceback (most recent call last):
  File "/home/src/sql_expression.py", line 864, in build_query
    source_query.append_column(sqlalchemy.literal(1).label('flagged'))
  File "<string>", line 2, in append_column
  File "/home/plaid/py39/lib/python3.9/site-packages/sqlalchemy/util/deprecations.py", line 390, in warned
    return fn(*args, **kwargs)
  File "/home/plaid/py39/lib/python3.9/site-packages/sqlalchemy/sql/selectable.py", line 3985, in append_column
    self.add_columns.non_generative(self, column)
  File "/home/plaid/py39/lib/python3.9/site-packages/sqlalchemy/sql/selectable.py", line 5261, in add_columns
    self._assert_no_memoizations()
  File "/home/plaid/py39/lib/python3.9/site-packages/sqlalchemy/util/langhelpers.py", line 1143, in _assert_no_memoizations
    assert elem not in self.__dict__
AssertionError

[zzzeek]

can you pdb in there, or do a print statement and show me the value of "elem" and self.__dict__? that will allow me to see what's not being handled.

[zzzeek]

importantly, while I can probably fix this assertion, doing so is likely going to still produce a non-working result on your end because if you are appending columns, that "implicit subquery" that is being accessed wont be correspondingly updated

[rad-pat]

OK, many thanks for the detailed reply. I'll take a look at the code that builds this query and see what I can fix there. I certainly know where it is doing the append_column so I can fix that immediately. Interestingly, I thought I was running with warnings enabled, I certainly see other warnings such as for asyncio - I'll look into that too!!

[zzzeek]

if it's not generating the warnings then we have to solve that too , do you have any warnings.filterwarnings in your program ?

[rad-pat]

Well, there we go... I thought I had warnings enabled but I did not. 🤦
I think those warnings will keep me busy a while!!!

[zzzeek]

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