Add permission reset after test writes to file

I haven't look at the test, many other tests set up modules in vfs instead of changing real files, would that be an option here?

If I'm following this right, the code in question is this:

foreach (scandir("core/modules/user/tests/modules/user_hooks_test") as $item) {
  $target = "$this->siteDirectory/$item";
  if (!file_exists($target)) {
    symlink(realpath("core/modules/user/tests/modules/user_hooks_test/$item"), $target);
  }
}

For a start, symlink() expects $target as the first parameter, but I think we're just using the wrong name for the variable. The target is where the symlink points to, which is the file in core/modules. The link we're creating is written to $this->siteDirectory which should be in sites/simpletest, which should be gitignored.

If I'm mistaken, can you point to where the test is writing to a file that is checked in to the repository?

Oh I found it.

In \Drupal\KernelTests\KernelTestBase::tearDown

// Delete test site directory.
$callback = function (string $path) {
  @chmod($path, 0700);
};

This is passed to \Drupal\Core\File\FileSystem::deleteRecursive and it's applied to every file. Perhaps we could just fix that to now chmod symlinks? I'm curious why we need to chmod a file that is going to be deleted anyway, if we have permission to set the permissions then surely we can just delete it?

This probably is eligible for backport but not sure it's worth the effort.

Committed and pushed cb176c7426f to 11.x and 1b5f6d95e32 to 11.3.x. Thanks!