Don't revert composer.json when "require" fails because of scripts

[nicolas-grekas]

Fix eg symfony/flex#751

[Seldaek]

I agree we should fix this as it's annoying, but I wonder if we could target only post-update scripts failures somehow.. Because if some script fails earlier than when the update is complete, we probably still want to revert.

[imme-emosol]

Would that be after

composer/src/Composer/Installer.php

Line 337 in 2cb1d4b

$this->eventDispatcher->dispatchScript($eventName, $this->devMode);

?

[Seldaek]

Let's say it'd be ok if anything fails from that point on (POST_UPDATE_CMD), but before that it should still revert IMO.

[Seldaek]

OK I think I found a relatively accurate way to fix this :)

[dzuelke]

@nicolas-grekas could you please check that #10541 does not break this (and symfony/flex#142) again?