Jinja: no test named 'None'

Created on 13 Dec 2015  ·  2Comments  ·  Source: pallets/jinja

Running into an issue where using a template like this {{"" if np is None else np}}, I get the following exception jinja2.exceptions.TemplateAssertionError: no test named 'None'. Trying with is not has similar problems.

picture jakirkham

Most helpful comment

Use lowercase none.

Jinja's is is different from Python's is. It invokes functions registered as "tests". And while there's a none test, there's no test named None.

Useful side-note: Jinja also uses lowercase for true and false, even though the python-cased True and False work too.

picture ThiefMaster on 13 Dec 2015
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All 2 comments

Use lowercase none.

Jinja's is is different from Python's is. It invokes functions registered as "tests". And while there's a none test, there's no test named None.

Useful side-note: Jinja also uses lowercase for true and false, even though the python-cased True and False work too.

ThiefMaster picture ThiefMaster on 13 Dec 2015
👍24

Thanks @ThiefMaster. I'm still pretty new to jinja, but it seems pretty cool. Thanks for the pointers too.

jakirkham picture jakirkham on 15 Dec 2015
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