Cannot update field data on numeric fields when formdata is processed

I think I encountered a bug related to how field values are rendered on numeric fields. I am trying to dynamically change some field values after the form has been submitted. It works on StringFields for example but not on IntegerFields.

Actual Behavior

from werkzeug.datastructures import ImmutableMultiDict
from wtforms import Form, IntegerField, StringField

class MyForm(Form):
    string_field = StringField("Name")
    integer_field = IntegerField("Value")

formdata = ImmutableMultiDict([("string_field", "World"), ("integer_field", "")])
form = MyForm(formdata=formdata)
assert form.string_field.data == "World"
assert form.integer_field.data is None

form.string_field.data = "Hello"
assert form.string_field.data == "Hello"
assert 'value="Hello"' in form.string_field()  # <- works

form.integer_field.data = 42
assert form.integer_field.data == 42
assert 'value="42"' in form.integer_field()  # <- AssertionError

Traceback (most recent call last):
  File "/tmp/test.py", line 21, in <module>
    assert 'value="42"' in form.integer_field()
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AssertionError

Expected Behavior

Allow setting the field data on numeric fields after formdata is processed. So the behaviour is aligned with other non-numeric fields.

Problem

Right now, all (or most) numeric fields use raw_data[0] if present for the fields value in the rendered HTML output.

def _value(self):
    if self.raw_data:
        return self.raw_data[0]
    if self.data is not None:
        return str(self.data)
    return ""

Environment

wtforms version: 3.0.1

EDIT: typo

pallets-eco / wtforms