IntegerField max_value & min_value errors require a %s

[Chris Jones <chris@…>]

When trying to set the max_value or min_value error message on an IntegerField without %s in the custom string a TypeError is raised.

Example: phone = forms.IntegerField(max_value=10 error_messages={'max_value': 'Please enter a phone number with 10 digits.')

Exception Type: TypeError
Exception Value: not all arguments converted during string formatting
Exception Location: /usr/local/lib/python2.5/site-packages/django/forms/fields.py in clean, line 185

To stop the TypeError from being raised I have to add %s somewhere in my custom error message string.
Example: phone = forms.IntegerField(max_value=10 error_messages={'max_value': 'Please enter a phone number with %s digits.')

Either the documentation needs to be updated to explain this or the error message should be able to handle a string with or without the max_value/min_value being called.

[Chris Beaven]

I agree, this isn't the best. The design decision is to be whether we should fix it or just update the docs.

Personally, I'd like to see them as parenthesized mapping keys ('Please enter a value less than %(max_value)s')

[Walter Ferreira]

I agree, make a custom min_value or max_value error_messages with %s or whitout %s must be enable for forms.IntegerField

[Håkan W]

Please, this really needs to be added to the documentation.

[Adam Vandenberg]

As of 1.3-alpha-1 (and possibly earlier), all form field error messages that have data available use mapping keys. I've opened a new ticket w/ a patch to document these keys: ​http://code.djangoproject.com/ticket/14708

Recommend resolving this issue as a duplicate of that new issue.

[Gabriel Hurley]

As adamv points out, the design decision seems to have been made (by standardizing the use of mapping keys for 1.3), so that would make this a docs ticket. And since adamv was kind enough to create #14708 with a complete patch (looks complete at least from a cursory review), I'm closing this as a duplicate.