Symfony version(s) affected

6.4

Description

When you have retrieved a multipart form that has a type="file" and do not not send a file back when submitting the form the code fails at

https://github.com/symfony/symfony/blob/6.4/src/Symfony/Component/Mime/Part/TextPart.php#L149

How to reproduce

I am sorry that I did not write PHP code to reproduce nor did I figure out your unit test framework to submit a unit test. Please forgive me and note that I have been a long-time sponsor of the project :)

Note that I am using this through several layers of abstraction - Guzzle, and my own abstration that I built on top of that - so I don't really know how to exercise mime directly to cause this, but submitting the following form that should reproduce the problem is as follows:

<form method="post" enctype="multipart/form-data">
    <textarea name="text" cols="40" rows="10">
    <input type="file" name="picture"> 
    <input type="submit" value="Submit">
</form>

Retrieve the form or set up the form, set text and ignore picture, then submit the form (or perhaps just tell mime to serialize the form in preparation for submission) - TextPart.php fails in line 149.

I wish I knew more about how my stack works top to bottom so I could give you a cool unit test - but alas this is the best I can do. Thanks for all you do.

Possible Solution

I have a copy of the code and was able to bypass the problem with the following quite imperfect workaround in the case where the file path is null.

tsugiproject/tsugi@4c471d3

This is not at all my recommended fix - it was just enough of a fix for my extremely limited use case that shows that (a) there is a series of calls that can lead to the the body path being null and (b) if you handle null things work better. I tried to trace the code upwards to make a smarter fix - but it was a morass of generators and magic yields that was difficult for me to lock down. I wish I could have yielded null or something other than a blank string - but that worked well enough for me for now.

Additional Context

Thanks in advance - love the work your are doing to bring the PHP framework world together. The fewer dependencies we have and the more professionally maintained those dependencies are - the better life is in PHP world.

Happy to be a long-time sponsor of this project. -- Chuck

P.S. Don't judge me too much putting the vendor folder in github :) You have no idea how scary it is to type composer update at the moment that my adopters are installing my software. As painful as my approach is, I know what they are running and know exactly what version of every dependency they are running. I can extensively test exactly one set of dependency versions than then hand it to my adopters who just do a git pull :) And it also lets me patch around a bug in a dependency and move my adopting community forward.