34 files declare their use of RequirementsException

CheckRequirementsTest.php in core/modules/migrate/tests/src/Unit/Plugin/migrate/destination/CheckRequirementsTest.php
CommentEntityTranslation.php in core/modules/comment/src/Plugin/migrate/source/d7/CommentEntityTranslation.php
CommentEntityTranslationCheckRequirementsTest.php in core/modules/comment/tests/src/Kernel/Migrate/d7/CommentEntityTranslationCheckRequirementsTest.php
CommentType.php in core/modules/comment/src/Plugin/migrate/source/CommentType.php
CommentTypeRequirementsTest.php in core/modules/comment/tests/src/Kernel/Plugin/migrate/source/CommentTypeRequirementsTest.php
CredentialForm.php in core/modules/migrate_drupal_ui/src/Form/CredentialForm.php
D6NodeDeriver.php in core/modules/node/src/Plugin/migrate/D6NodeDeriver.php
D7NodeDeriver.php in core/modules/node/src/Plugin/migrate/D7NodeDeriver.php
D7TaxonomyTermDeriver.php in core/modules/taxonomy/src/Plugin/migrate/D7TaxonomyTermDeriver.php
DestinationBase.php in core/modules/migrate/src/Plugin/migrate/destination/DestinationBase.php
DrupalSqlBase.php in core/modules/migrate_drupal/src/Plugin/migrate/source/DrupalSqlBase.php
DrupalSqlBaseTest.php in core/modules/migrate_drupal/tests/src/Unit/source/DrupalSqlBaseTest.php
FieldDiscovery.php in core/modules/migrate_drupal/src/FieldDiscovery.php
MigrateDependenciesTest.php in core/modules/migrate_drupal/tests/src/Kernel/dependencies/MigrateDependenciesTest.php
MigrateDrupalHooks.php in core/modules/migrate_drupal/src/Hook/MigrateDrupalHooks.php
MigrateExecutable.php in core/modules/migrate/src/MigrateExecutable.php
MigrateImageCacheTest.php in core/modules/image/tests/src/Kernel/Migrate/d6/MigrateImageCacheTest.php
MigrateMessageController.php in core/modules/migrate/src/Controller/MigrateMessageController.php
MigrateMissingDatabaseTest.php in core/modules/migrate/tests/src/Kernel/MigrateMissingDatabaseTest.php
migrate_drupal.module in core/modules/migrate_drupal/migrate_drupal.module
Provides migration from other Drupal sites.
Migration.php in core/modules/migrate/src/Plugin/Migration.php
MigrationConfigurationTrait.php in core/modules/migrate_drupal/src/MigrationConfigurationTrait.php
MigrationPluginListTest.php in core/modules/migrate/tests/src/Kernel/Plugin/MigrationPluginListTest.php
MigrationTest.php in core/modules/migrate/tests/src/Unit/MigrationTest.php
ProfileField.php in core/modules/user/src/Plugin/migrate/source/ProfileField.php
ProfileFieldCheckRequirementsTest.php in core/modules/user/tests/src/Kernel/Migrate/d6/ProfileFieldCheckRequirementsTest.php
ProfileFieldCheckRequirementsTest.php in core/modules/user/tests/src/Kernel/Migrate/d7/ProfileFieldCheckRequirementsTest.php
ProfileValues.php in core/modules/user/src/Plugin/migrate/ProfileValues.php
RequirementsExceptionTest.php in core/modules/migrate/tests/src/Unit/Exception/RequirementsExceptionTest.php
SqlBase.php in core/modules/migrate/src/Plugin/migrate/source/SqlBase.php
SqlBaseTest.php in core/modules/migrate/tests/src/Kernel/SqlBaseTest.php
User.php in core/modules/user/src/Plugin/migrate/User.php
VariableTranslation.php in core/modules/migrate_drupal/src/Plugin/migrate/source/d6/VariableTranslation.php
VariableTranslationCheckRequirementsTest.php in core/modules/migrate_drupal/tests/src/Kernel/d6/VariableTranslationCheckRequirementsTest.php

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