Document that "empty_data" requires data in view format

[webmozart]

It should be documented with the "empty_data" option that the data must be passed in view format, in case that differs from model format. For IntegerType, for example, "empty_data" must be set to a string value, not an integer (conversely to what you would intuitively expect):

$builder->add('number', IntegerType::class, [
    'empty_data' => '0', // not: 0
]);

See symfony/symfony#18047

[xabbuh]

@HeahDude kindly offered to take care of this together with his other changes in #6265.

[conradkleinespel]

Thanks @webmozart for taking the time to open this issue (I was just having this exact problem). And thanks @HeahDude for making a doc PR 😃

[carsonbot]

Thank you for this issue.
There has not been a lot of activity here for a while. Has this been resolved?