How to use WTForms' TableWidget?

Question

I want to use WTForms to render a form in a table. It seems like the TableWidget will do the trick, but the only way I can get this to work is as follows:

from wtforms import Form, TextField, widgets

class User(Form):
    user = TextField('User')
    email = TextField('Password')

    widget = widgets.TableWidget(with_table_tag=False)

user = User()
print user.widget(user)

This seems weird (the print user.widget(user) part) According to the documentation, I ought to be able to say:

class User(Form):
    user = TextField('User', widget=widgets.TableWidget)
    email = TextField('Password', widget=widgets.TableWidget)

user = User()
for form_field in user:
    print form_field

However, this returns TypeError: __str__ returned non-string (type TableWidget)

When I replace user, email with:

user = TextField('User')
email = TextField('Password')

Then of course the WTForms rendering works as expected.

How does this work?

Answer 1

In the docs it says the following about TableWidget

Renders a list of fields as a set of table rows with th/td pairs.

You are associating it a with single field instead of a list of fields. If you look in the code the __call__ method of TableWidget expects an argument called field but it treats it as an iterable for purposes of generating the html string.