48 files declare their use of RouteObjectInterface

AccessAwareRouterTest.php in core/tests/Drupal/Tests/Core/Routing/AccessAwareRouterTest.php
AccessManager.php in core/lib/Drupal/Core/Access/AccessManager.php
AccessManagerTest.php in core/tests/Drupal/Tests/Core/Access/AccessManagerTest.php
Contains \Drupal\Tests\Core\Access\AccessManagerTest.
AuthenticationManagerTest.php in core/tests/Drupal/Tests/Core/Authentication/AuthenticationManagerTest.php
Contains \Drupal\Tests\Core\Authentication\AuthenticationManagerTest.
authorize.php in core/authorize.php
Administrative script for running authorized file operations.
CurrentRouteMatchTest.php in core/tests/Drupal/Tests/Core/Routing/CurrentRouteMatchTest.php
EntityBundleRouteEnhancer.php in core/lib/Drupal/Core/Entity/Enhancer/EntityBundleRouteEnhancer.php
EntityRevisionRouteEnhancer.php in core/lib/Drupal/Core/Routing/Enhancer/EntityRevisionRouteEnhancer.php
EntityRevisionRouteEnhancerTest.php in core/tests/Drupal/Tests/Core/Enhancer/EntityRevisionRouteEnhancerTest.php
EntityRouteEnhancer.php in core/lib/Drupal/Core/Entity/Enhancer/EntityRouteEnhancer.php
EntityRouteEnhancerTest.php in core/tests/Drupal/Tests/Core/Entity/Enhancer/EntityRouteEnhancerTest.php
EntityUrlLanguageTest.php in core/modules/language/tests/src/Kernel/EntityUrlLanguageTest.php
EntityUuidConverter.php in core/modules/jsonapi/src/ParamConverter/EntityUuidConverter.php
FormRouteEnhancer.php in core/lib/Drupal/Core/Routing/Enhancer/FormRouteEnhancer.php
FunctionalTestSetupTrait.php in core/lib/Drupal/Core/Test/FunctionalTestSetupTrait.php
install.core.inc in core/includes/install.core.inc
API functions for installing Drupal.
KernelTestBase.php in core/tests/Drupal/KernelTests/KernelTestBase.php
LanguageNegotiationContentEntity.php in core/modules/language/src/Plugin/LanguageNegotiation/LanguageNegotiationContentEntity.php
LanguageNegotiationContentEntityTest.php in core/modules/language/tests/src/Functional/LanguageNegotiationContentEntityTest.php
LanguageNegotiationUserAdmin.php in core/modules/user/src/Plugin/LanguageNegotiation/LanguageNegotiationUserAdmin.php
LayoutTempstoreRouteEnhancer.php in core/modules/layout_builder/src/Routing/LayoutTempstoreRouteEnhancer.php
LayoutTempstoreRouteEnhancerTest.php in core/modules/layout_builder/tests/src/Unit/LayoutTempstoreRouteEnhancerTest.php
MenuActiveTrailTest.php in core/tests/Drupal/Tests/Core/Menu/MenuActiveTrailTest.php
MenuLinkContentCacheabilityBubblingTest.php in core/modules/menu_link_content/tests/src/Kernel/MenuLinkContentCacheabilityBubblingTest.php
ParamConversionEnhancer.php in core/lib/Drupal/Core/Routing/Enhancer/ParamConversionEnhancer.php
ParamConversionEnhancerTest.php in core/tests/Drupal/Tests/Core/Enhancer/ParamConversionEnhancerTest.php
ParamConverterManager.php in core/lib/Drupal/Core/ParamConverter/ParamConverterManager.php
ParamConverterManagerTest.php in core/tests/Drupal/Tests/Core/ParamConverter/ParamConverterManagerTest.php
PathBasedBreadcrumbBuilderTest.php in core/modules/system/tests/src/Unit/Breadcrumbs/PathBasedBreadcrumbBuilderTest.php
Contains \Drupal\Tests\system\Unit\Breadcrumbs\PathBasedBreadcrumbBuilderTest.
PathValidator.php in core/lib/Drupal/Core/Path/PathValidator.php
PathValidatorTest.php in core/tests/Drupal/Tests/Core/Path/PathValidatorTest.php
ResourceResponseValidatorTest.php in core/modules/jsonapi/tests/src/Unit/EventSubscriber/ResourceResponseValidatorTest.php
ResourceVersionRouteEnhancer.php in core/modules/jsonapi/src/Revisions/ResourceVersionRouteEnhancer.php
RouteMatchTest.php in core/tests/Drupal/Tests/Core/Routing/RouteMatchTest.php
RouteNoneTest.php in core/tests/Drupal/KernelTests/Core/RouteProcessor/RouteNoneTest.php
RouteProcessorCurrentIntegrationTest.php in core/tests/Drupal/KernelTests/Core/RouteProcessor/RouteProcessorCurrentIntegrationTest.php
Routes.php in core/modules/jsonapi/src/Routing/Routes.php
RoutesTest.php in core/modules/jsonapi/tests/src/Unit/Routing/RoutesTest.php
SpecialAttributesRouteSubscriber.php in core/lib/Drupal/Core/EventSubscriber/SpecialAttributesRouteSubscriber.php
SpecialAttributesRouteSubscriberTest.php in core/tests/Drupal/Tests/Core/EventSubscriber/SpecialAttributesRouteSubscriberTest.php
SystemMenuBlockTest.php in core/modules/system/tests/src/Kernel/Block/SystemMenuBlockTest.php
TestControllers.php in core/modules/system/tests/modules/router_test_directory/src/TestControllers.php
ThemeTest.php in core/modules/system/tests/src/Functional/Theme/ThemeTest.php
UpdateKernel.php in core/lib/Drupal/Core/Update/UpdateKernel.php
Url.php in core/lib/Drupal/Core/Url.php
UrlTest.php in core/tests/Drupal/Tests/Core/UrlTest.php
Contains \Drupal\Tests\Core\UrlTest.
ViewPageControllerTest.php in core/modules/views/tests/src/Unit/Routing/ViewPageControllerTest.php
ViewUI.php in core/modules/views_ui/src/ViewUI.php

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