19 files declare their use of RouteBuildEvent

AdminRouteSubscriberTest.php in core/modules/system/tests/src/Unit/Routing/AdminRouteSubscriberTest.php
ContentModerationRouteSubscriberTest.php in core/modules/content_moderation/tests/src/Unit/ContentModerationRouteSubscriberTest.php
EntityResourcePostRouteSubscriber.php in core/modules/rest/src/EventSubscriber/EntityResourcePostRouteSubscriber.php
EntityRouteAlterSubscriber.php in core/lib/Drupal/Core/EventSubscriber/EntityRouteAlterSubscriber.php
EntityRouteProviderSubscriber.php in core/lib/Drupal/Core/EventSubscriber/EntityRouteProviderSubscriber.php
LayoutBuilderRoutes.php in core/modules/layout_builder/src/Routing/LayoutBuilderRoutes.php
LayoutBuilderRoutesTest.php in core/modules/layout_builder/tests/src/Unit/LayoutBuilderRoutesTest.php
ModuleRouteSubscriberTest.php in core/tests/Drupal/Tests/Core/EventSubscriber/ModuleRouteSubscriberTest.php
NoBigPipeRouteAlterSubscriber.php in core/modules/big_pipe/src/EventSubscriber/NoBigPipeRouteAlterSubscriber.php
ParamConverterSubscriber.php in core/lib/Drupal/Core/EventSubscriber/ParamConverterSubscriber.php
PathRootsSubscriber.php in core/lib/Drupal/Core/EventSubscriber/PathRootsSubscriber.php
PathRootsSubscriberTest.php in core/tests/Drupal/Tests/Core/EventSubscriber/PathRootsSubscriberTest.php
ResourceRoutes.php in core/modules/rest/src/Routing/ResourceRoutes.php
RouteBuilderTest.php in core/tests/Drupal/Tests/Core/Routing/RouteBuilderTest.php
Contains \Drupal\Tests\Core\Routing\RouteBuilderTest.
RouteMethodSubscriber.php in core/lib/Drupal/Core/EventSubscriber/RouteMethodSubscriber.php
RouteSubscriberTest.php in core/modules/views/tests/src/Unit/EventSubscriber/RouteSubscriberTest.php
Contains \Drupal\Tests\views\Unit\EventSubscriber\RouteSubscriberTest.
SpecialAttributesRouteSubscriber.php in core/lib/Drupal/Core/EventSubscriber/SpecialAttributesRouteSubscriber.php
SpecialAttributesRouteSubscriberTest.php in core/tests/Drupal/Tests/Core/EventSubscriber/SpecialAttributesRouteSubscriberTest.php
UserRouteAlterSubscriber.php in core/modules/serialization/src/EventSubscriber/UserRouteAlterSubscriber.php

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