symfony/mime v5.2.0 broken file upload

[naelsaid]

Symfony version(s) affected: symfony/mime v5.2.0

Description
Today I ran composer update for a project and found that file uploads in all forms broke. After investigating the problem I figured out that if I go back to symfony/mime v5.1.9 everything works again.

Our project uses Laravel 8 which in turn uses symfony/mime

[Nyholm]

Thank you.
Could you show some a minimal example of what is broken?

[naelsaid]

Unfortunately I am not an expert in debugging such kind of errors. All I can provide is that in Laravel I get the error

Illuminate\Validation\ValidationException: The given data was invalid

When I upload an image.
this is the validation rules set for the uploaded image

'mimes' => 'png,jpg,gif,jpeg',

Hope it helps.

i thought it might be a Laravel issue but when I downgrade symfony/mime to v5.1.9 everything works like normal. So I do not think it is a Laravel issue.

[Nyholm]

Hm.. We are very much in the "Something is wrong" area. =)

I need something more.

It sounds like you have an image upload form and validation that it only accepts some specific extensions. But you get a validation error.

I see on your validation rules you have mimes key and the value is a list of extensions. That does not look correct.

Is there an extensions key you can use instead? Or will it be better if you used mimes instead? Example mime is: image/png

[fragkp]

I tracked the issue further to this file:
https://github.com/symfony/symfony/blob/5.x/src/Symfony/Component/HttpFoundation/File/File.php#L61

getExtensions() from the MimeTypes class returns a different order for image/jpeg mime.

5.1:

array:3 [
  0 => "jpeg"
  1 => "jpg"
  2 => "jpe"
]

5.2:

array:3 [
  0 => "jpg"
  1 => "jpeg"
  2 => "jpe"
]

[Nyholm]

Thank you @fragkp. You are correct. But that is fine, ie, there is no BC break and @mnaas code should not fail because of it.

[naelsaid]

Yes I was investigating and found the same problem
I opened an issue where I do not know if this is a Laravel or Symfony/mime issue
laravel/framework#35417

[Nyholm]

Thank you for the reports.

@fragkp found the cause of this change and @NEGits fixed it in laravel/framework#35416

Awesome work!

[driesvints]

Not that I want to start a discussion around this @Nyholm but imo this is a change in behavior which should be considered a BC break. It's a gray area for sure. Anyway, I think we can work around this easily. Thanks for your work 👍

[mfn]

FTR, the actually merged PR for 6.x was laravel/framework#35419

[Nyholm]

Awesome!