Incompatible with composer 2.2.8

[andrewbelcher]

Describe the bug
On updating to composer 2.2.8 (released this morning), all composer commands now fail. I believe this is due to BLT providing an installer path for drupal core which then conflicts with any real project.

To Reproduce
Steps to reproduce the behavior, ideally starting from a fresh install of BLT:

1. Run composer create-project acquia/blt-project --no-interaction
2. Run composer validate

Expected behavior
Success

Detailed error output

Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Component/DependencyInjection/Container.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Component/DependencyInjection/PhpArrayContainer.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Component/FileCache/FileCacheFactory.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Component/Utility/Timer.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Component/Utility/Unicode.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Cache/Cache.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Cache/CacheBackendInterface.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Cache/CacheTagsChecksumInterface.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Cache/CacheTagsChecksumTrait.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Cache/CacheTagsInvalidatorInterface.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Cache/DatabaseBackend.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Cache/DatabaseCacheTagsChecksum.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Database/Connection.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Database/Database.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Database/Driver/mysql/Connection.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Database/Driver/pgsql/Connection.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Database/Driver/sqlite/Connection.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Database/Statement.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Database/StatementInterface.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/DependencyInjection/Container.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/DrupalKernel.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/DrupalKernelInterface.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Installer/InstallerRedirectTrait.php" which does not appear to be a file nor a folder
Could not scan for classes inside "/var/www/html/vendor/drupal/core/lib/Drupal/Core/Site/Settings.php" which does not appear to be a file nor a folder

                                                                                                                     
  [ErrorException]                                                                                                   
  require(/var/www/html/vendor/drupal/core/includes/bootstrap.inc): failed to open stream: No such file or director  
  y

Additional context
composer/composer#10618

[mikemadison13]

I've confirmed this issue on one of my codebases with 2.2.8. Having a look at the linked composer issue, BLT may need to change something (along with some of our recommended projects, which I will alert our teams on). But I think we may be blocked from doing so until we get some clarity on 10618 in the composer/composer queue!

[Seldaek]

See composer/composer#10618 (comment)

[andrewbelcher]

Given the discussion in the composer issue, it seems this should either be solved in composer + composer/installers, or in drupal/core. The composer issue is looking at the former and I've opened https://www.drupal.org/project/drupal/issues/3269695 for consideration of the latter.