[HttpKernel] Preventing error 500 when function putenv is disabled

[ShaiMagal]

Q	A
Branch?	5.4
Bug fix?	yes
New feature?	no
Deprecations?	no
Issues
License	MIT

Description:
Some webhostings are blocking function "putenv". So, it will show error 500 Error (UndefinedFunction) with text:
Attempted to call function "putenv" from namespace "Symfony\Component\HttpKernel

This PR is checking callability of putenv first, so preventing error 500.

How to test?
-> php.ini - disabled_functions=putenv
-> enable debug

• Then you will see error 500
  -> After this PR/commit, it's without problem.

For example it's very common problem for PrestaShop users. (PrestaShop is using Symfony)

[carsonbot]

Hey!

I see that this is your first PR. That is great! Welcome!

Symfony has a contribution guide which I suggest you to read.

In short:

• Always add tests
• Keep backward compatibility (see https://symfony.com/bc).
• Bug fixes must be submitted against the lowest maintained branch where they apply (see https://symfony.com/releases)
• Features and deprecations must be submitted against the 6.4 branch.

Review the GitHub status checks of your pull request and try to solve the reported issues. If some tests are failing, try to see if they are failing because of this change.

When two Symfony core team members approve this change, it will be merged and you will become an official Symfony contributor!
If this PR is merged in a lower version branch, it will be merged up to all maintained branches within a few days.

I am going to sit back now and wait for the reviews.

Cheers!

Carsonbot

[ShaiMagal]

@stof Updated :)

[ShaiMagal]

Guys, will this be merged with branch 6.x as well in future or I should make another PR specially for 6.x? (this PR I targeted to 5.4 but I don't know if this will be at 6.x in future... so I am asking, how to do this correctly.

Thank you.

[stof]

@ShaiMagal this will be merged up by the core team once this PR is merged (the merge up happens usually once a week for dev version, and it will happen for sure before tagging a release)

[fabpot]

Should we do the same in src/Symfony/Component/BrowserKit/AbstractBrowser.php and src/Symfony/Component/Runtime/SymfonyRuntime.php?

[nicolas-grekas]

I had a look and I don't think we need to: AbstractBrowser + the spot in Runtime are for command line usages, and to me those are not affected by (cheap) hosters.

[fabpot]

Thank you @ShaiMagal.