39 files declare their use of PreApplyEvent

AllowedScaffoldPackagesValidator.php in core/modules/package_manager/src/Validator/AllowedScaffoldPackagesValidator.php
AllowedScaffoldPackagesValidatorTest.php in core/modules/package_manager/tests/src/Kernel/AllowedScaffoldPackagesValidatorTest.php
BaseRequirementsFulfilledValidator.php in core/modules/package_manager/src/Validator/BaseRequirementsFulfilledValidator.php
BaseRequirementsFulfilledValidatorTest.php in core/modules/package_manager/tests/src/Kernel/BaseRequirementsFulfilledValidatorTest.php
BaseRequirementValidatorTrait.php in core/modules/package_manager/src/Validator/BaseRequirementValidatorTrait.php
ComposerPatchesValidator.php in core/modules/package_manager/src/Validator/ComposerPatchesValidator.php
ComposerPluginsValidator.php in core/modules/package_manager/src/Validator/ComposerPluginsValidator.php
ComposerPluginsValidatorTest.php in core/modules/package_manager/tests/src/Kernel/ComposerPluginsValidatorTest.php
ComposerValidator.php in core/modules/package_manager/src/Validator/ComposerValidator.php
ComposerValidatorTest.php in core/modules/package_manager/tests/src/Kernel/ComposerValidatorTest.php
DiskSpaceValidatorTest.php in core/modules/package_manager/tests/src/Kernel/DiskSpaceValidatorTest.php
DuplicateInfoFileValidator.php in core/modules/package_manager/src/Validator/DuplicateInfoFileValidator.php
EnabledExtensionsValidator.php in core/modules/package_manager/src/Validator/EnabledExtensionsValidator.php
EnabledExtensionsValidatorTest.php in core/modules/package_manager/tests/src/Kernel/EnabledExtensionsValidatorTest.php
EnvironmentSupportValidatorTest.php in core/modules/package_manager/tests/src/Kernel/EnvironmentSupportValidatorTest.php
EventLogSubscriber.php in core/modules/package_manager/tests/modules/package_manager_test_event_logger/src/EventSubscriber/EventLogSubscriber.php
LockFileValidator.php in core/modules/package_manager/src/Validator/LockFileValidator.php
LockFileValidatorTest.php in core/modules/package_manager/tests/src/Kernel/LockFileValidatorTest.php
MultisiteValidatorTest.php in core/modules/package_manager/tests/src/Kernel/MultisiteValidatorTest.php
OverwriteExistingPackagesValidator.php in core/modules/package_manager/src/Validator/OverwriteExistingPackagesValidator.php
OverwriteExistingPackagesValidatorTest.php in core/modules/package_manager/tests/src/Kernel/OverwriteExistingPackagesValidatorTest.php
PackageManagerKernelTestBase.php in core/modules/package_manager/tests/src/Kernel/PackageManagerKernelTestBase.php
PendingUpdatesValidator.php in core/modules/package_manager/src/Validator/PendingUpdatesValidator.php
PhpExtensionsValidator.php in core/modules/package_manager/src/Validator/PhpExtensionsValidator.php
PhpExtensionsValidatorTest.php in core/modules/package_manager/tests/src/Kernel/PhpExtensionsValidatorTest.php
PhpTufValidator.php in core/modules/package_manager/src/Validator/PhpTufValidator.php
PhpTufValidatorTest.php in core/modules/package_manager/tests/src/Kernel/PhpTufValidatorTest.php
SettingsValidator.php in core/modules/package_manager/src/Validator/SettingsValidator.php
SettingsValidatorTest.php in core/modules/package_manager/tests/src/Kernel/SettingsValidatorTest.php
SiteConfigurationExcluder.php in core/modules/package_manager/src/PathExcluder/SiteConfigurationExcluder.php
StageBase.php in core/modules/package_manager/src/StageBase.php
StageBaseTest.php in core/modules/package_manager/tests/src/Kernel/StageBaseTest.php
StageEventsTest.php in core/modules/package_manager/tests/src/Kernel/StageEventsTest.php
StageNotInActiveValidator.php in core/modules/package_manager/src/Validator/StageNotInActiveValidator.php
SupportedReleaseValidator.php in core/modules/package_manager/src/Validator/SupportedReleaseValidator.php
SupportedReleaseValidatorTest.php in core/modules/package_manager/tests/src/Kernel/SupportedReleaseValidatorTest.php
TestSubscriber.php in core/modules/package_manager/tests/modules/package_manager_test_validation/src/EventSubscriber/TestSubscriber.php
WritableFileSystemValidator.php in core/modules/package_manager/src/Validator/WritableFileSystemValidator.php
WritableFileSystemValidatorTest.php in core/modules/package_manager/tests/src/Kernel/WritableFileSystemValidatorTest.php

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