Neos.Flow: InstallerScripts class for composer is not compatible with composer 2

[robert-heinig]

In
https://github.com/neos/flow-development-collection/blob/master/Neos.Flow/composer.json
there is a dependency to "composer/composer": "^1.9" but composer did not complain while upgrading a Neos 5.2 to 5.3 with composer 2 RC1.

In
https://github.com/neos/flow-development-collection/blob/master/Neos.Flow/Classes/Composer/InstallerScripts.php
wihtin the method postPackageUpdateAndInstall() the call $operation->getJobType() is used 4 times.
This method getJobType was renamed to getOperationType within composer 2:
composer/composer@5bdc0fc#diff-fbab13faf7a9485e442e629e12f0f31a

With the composer dependency to ^1.9 not seeming to work properly I'm not sure how to solve this issue correctly.
A check with method_exists() is a possibility, but that seems not to be a nice solution.

Within my Neos project I'm using cweagans/composer-patches and a composer patch file that renames the method.

[albe]

Thanks for bringing this up! Since we're likely to have to support composer 1.x & 2.x for some time and the installer scripts is basically glue code between the infrastructure software and us, something like the method_exists() check is probably okay.

So if anyone is willing to play around, feel free to start a PR!
First thing would be to make the composer require a "^1.9 || ^2.0".

Note: Our composer plugin is already supposed to be composer 2.x compatible as of neos/composer-plugin#13

See composer/composer#8726
https://github.com/composer/composer/blob/master/UPGRADE-2.0.md#for-integrators-and-plugin-authors

[kdambekalns]

Fixed with latest release(s), see also #2187