IntegerField behaves strange

[igungor]

# coding: utf-8

import wtforms

wtforms.__version__
>>> 1.0.5

class Test(wtforms.Form):
    t = wtforms.fields.IntegerField('test', validators=[wtforms.validators.required(), wtforms.validators.number_range(min=3, message='unacceptable.')])

f = Test(t=1)
f.validate()
>>> False

f.errors
{'t': ['unacceptable.']}

f = Test(t=0)
f.validate()
>>> False

f.errors
{'t': [u'This field is required.']}

f = Test(t='hello')
f.validate()
>>> True

IntegerField accepts string(?), and "required" validator evaluates "0 (int)" as False as it seems.

Am I doing something wrong?

[Le-Stagiaire]

From doc :
" class wtforms.fields.IntegerField(default field arguments)
A text field, except all input is coerced to an integer. Erroneous input is ignored and will not be accepted as a value."
That means you enter a string and coerced it to an integer, so basically it would be like :
f = Test(t='1'), which will be coerce, after validation, to number 1.

I understand the doc like this, maybe I'm wrong

[crast]

Use the InputRequired validator instead of DataRequired, or don't use a Required validator.

[igungor]

Well, this example is the same but InputRequired:

# coding: utf-8

import wtforms

wtforms.__version__
>>> 1.0.5

class Test(wtforms.Form):
    t = wtforms.fields.IntegerField('test', validators=[wtforms.validators.InputRequired(), wtforms.validators.number_range(min=3, message='unacceptable.')])

f = Test(t=1)
f.validate()
>>> False

f.errors
{'t': ['This field is required.']}

f = Test(t=0)
f.validate()
>>> False

f.errors
{'t': ['This field is required.']}

f = Test(t='hello')
f.validate()
>>> False

f.errors
{'t': ['This field is required.']}

and this one is without any "required":

# coding: utf-8

import wtforms

wtforms.__version__
>>> 1.0.5

class Test(wtforms.Form):
    t = wtforms.fields.IntegerField('test', validators=[wtforms.validators.number_range(min=3, message='unacceptable.')])

f = Test(t=1)
f.validate()
>>> False

f.errors
{'t': ['unacceptable.']}  // Correct.

f = Test(t=0)
f.validate()
>>> False

f.errors
{'t': ['unacceptable.']}  // Correct

f = Test(t='hello')
f.validate()
>>> True  // Nope.

Why is string "hello" validated even though the field is Integer and there is a number_range validator?

I suspect that this is a bug.

[crast]

Fields only coerce form data, they don't coerce object data, this lets people use objects "like an int" and still have them work without the value being clobbered. It's your responsibility to pass correct datatypes to object/kwargs data.

And the reason why "hello" validates is just one of those weird artifacts of python:

>>> "hello" > 3
True
>>> "foo" > 3
True
>>> "" > 3
True

The entire point of the required / inputrequired validators is to stop further validators from running (and post a message) if the requirement isn't met. If you don't want that happening, then don't use the required validator.