Handling empty list of candidates in select_template function

[Silver_Ghost]

django.template.loader.select_template expects list of template names and select first loadable. If there are some template names in list and no one from them couldn't be loaded then raising TemplateDoesNotExist exception is the right decision. But if there isn't any template names in the list then >>Template<<DoesNotExist is wrong exception, I think.

So maybe checks if list is empty and raise exception with message like "I can't load any template for you because you didn't gave me any possible variants"?

[Silver_Ghost]

handling empty list of candidates for select_template

[Carl Meyer]

I don't think we need to change the exception class here; TemplateDoesNotExist is an ok exception to raise in this case. Changing it to ValueError could break existing code; it's not worth it.

Accepting this on the basis that it would be nice to provide a clearer message to the TemplateDoesNotExist error, rather than an empty message.

Also, test needed.

[Silver_Ghost]

Switching to TemplateDoesNotExist exception and adding tests

[Silver_Ghost]

The patch changed according to ticket:16866#comment:1.

[Preston Holmes]

while the term candidate has apparently been introduced in the class-based-views docs - it is a relatively new term, and one that could confuse people.

Since the documentation refers specifically to a "list of template names" I would just use an error string of "list of template names was empty"

[Carl Meyer]

In [16861]:

Fixed #16866 -- Clearer error message if empty list is passed to select_template. Thanks Silver_Ghost for report and patch.