"in" / "not in" do not work as expected.

[sparkslabs]

First of all thanks for writing this. I saw the recording of your talk on this on youtube from a pycon or similar and thought it worth trying. Works really well over all. Many thanks!

With that, the bug report...

Expected Behaviour

The following works in CPython:

resource_id = "foo"
user_resources_done = []

if resource_id not in user_resources_done:
    print("Gotta do that")
else:
    print("Done it")

Specifically it generates the following output:

>>> resource_id = "foo"
>>> user_resources_done = []
>>> if resource_id not in user_resources_done:
...     print("Gotta do that")
... else:
...     print("Done it")
... 
Gotta do that
>>> 

Current Behavior

In Batavia, if I use the same code, I get this:

Traceback (most recent call last):
  File "/tmp/tmpsrv0plrf", line 3, in <module>
ValueError: list.index(x): x not in list

Clearly this is a difference in behaviour.

Steps to reproduce

Using the testserver, copy and paste the above code into the "Run your code!" box, and hit "Run your code!"

Your Environment

• Batavia version - 3.4.0-dev.19
• Batavia git hash -- 458cb412bf312738980cdf45f6bc1c53c4634d44 (Dated Sun Mar 4 15:26:23 2018 +0800)
• Ubuntu Linux 16.04.04 -- LTS
• Python -- 3.5.2
• node -- v6.13.1
• npm -- 5.7.1

Workaround

Obviously this can be worked around in Batavia, but I thought it enough of an issue to raise since the obvious workarounds would only work in Batavia with this bug, not in CPython nor Batavia without this bug.

[freakboy3742]

Thanks for the comprehensive bug report! Looks like the definition of __contains__ on lists is a bit naïve.

[noahhaasis]

Is this still open? @vn-ki seems to have solved this.