Prevent validators from getting inserted twice

[pawl]

Related to this flask-admin issue: pallets-eco/flask-admin#1094

Edit: See this unit test for an example of the issue: https://github.com/coleifer/wtf-peewee/pull/32/files

If you override field_args with your own dict, the changes made to kwargs in convert() will also be made to the dict you used to override field_args. The objects that get copied to kwargs from field_args are only references, so you need to deepcopy to prevent the issue.

[coleifer]

Danke

[ak4nv]

I've got an error in my way with deepcode using.
TypeError: cannot deepcopy this pattern object

PolicyForm = model_form(Policy, Form,
                        field_args={
                            'pol_num': dict(validators=[optional()]),
                            'pol_reg': dict(validators=[optional()])})

Python 3.5 with latest flask, peewee, wtforms and wtfpeewee

[pawl]

I wasn't able to reproduce the issue in python 2 or 3 using validators.Optional() from wtforms 2.0.2: https://gist.github.com/pawl/9e12f0f8d0d482ece2a7

How are you defining optional()?

I can only reproduce the error when I do something like:

BlogForm = model_form(Blog, field_args={
    'name': dict(validators=[re.compile('eam3')]),
})

[ak4nv]

Sorry, I used modify code... there is full part:

from wtforms.validators import required, regexp, length

digits_only = regexp('^\d+$', message='Допустимы только цифры.')
fixed_length = lambda x: length(min=x, max=x)

PolicyForm = model_form(Policy, Form,
                        field_args={
                            'pol_num': dict(validators=[digits_only]),
                            'pol_reg': dict(validators=[digits_only, fixed_length(2)])})

But I tried with optional() from wtf.validarors and got the same error.

[pawl]

Hmm, I'm getting the same issue.

I guess I'll need to figure out a different way to prevent field_args from getting modified.

[ak4nv]

@coleifer set tag please to last commit 0.2.6(?) ;)