77 files declare their use of FormState

AggregatorPluginSettingsBaseTest.php in core/modules/aggregator/tests/src/Unit/Plugin/AggregatorPluginSettingsBaseTest.php
AreaDisplayLinkTest.php in core/modules/views/tests/src/Kernel/Handler/AreaDisplayLinkTest.php
AreaEntityTest.php in core/modules/views/tests/src/Kernel/Handler/AreaEntityTest.php
ArgumentValidateTest.php in core/modules/user/tests/src/Kernel/Views/ArgumentValidateTest.php
batch.inc in core/includes/batch.inc
Batch processing API for processes to run in multiple HTTP requests.
BatchTestController.php in core/modules/system/tests/modules/batch_test/src/Controller/BatchTestController.php
batch_test.module in core/modules/system/tests/modules/batch_test/batch_test.module
Helper module for the Batch API tests.
BlockInterfaceTest.php in core/modules/block/tests/src/Kernel/BlockInterfaceTest.php
ClaroVerticalTabsTest.php in core/tests/Drupal/KernelTests/Core/Theme/ClaroVerticalTabsTest.php
ConfigFormTestBase.php in core/tests/Drupal/KernelTests/ConfigFormTestBase.php
ConfigSingleExportForm.php in core/modules/config/src/Form/ConfigSingleExportForm.php
ContentTranslationHandlerTest.php in core/modules/content_translation/tests/src/Kernel/ContentTranslationHandlerTest.php
DatelistElementFormTest.php in core/tests/Drupal/KernelTests/Core/Datetime/DatelistElementFormTest.php
DatetimeElementFormTest.php in core/tests/Drupal/KernelTests/Core/Datetime/DatetimeElementFormTest.php
DateTimeFormInjectionTest.php in core/modules/datetime/tests/src/Kernel/DateTimeFormInjectionTest.php
DbLogFormInjectionTest.php in core/modules/dblog/tests/src/Kernel/DbLogFormInjectionTest.php
DisplayVariantTest.php in core/tests/Drupal/Tests/Core/Display/DisplayVariantTest.php
EditorImageDialogTest.php in core/modules/editor/tests/src/Kernel/EditorImageDialogTest.php
EditorMediaDialogTest.php in core/modules/media/tests/src/Kernel/EditorMediaDialogTest.php
ElementsFieldsetTest.php in core/modules/system/tests/src/Kernel/Form/ElementsFieldsetTest.php
ElementsTableSelectTest.php in core/modules/system/tests/src/Functional/Form/ElementsTableSelectTest.php
EntityAutocompleteElementFormTest.php in core/tests/Drupal/KernelTests/Core/Entity/Element/EntityAutocompleteElementFormTest.php
EntityDisplayFormBaseTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityDisplayFormBaseTest.php
EntityFormBuilder.php in core/lib/Drupal/Core/Entity/EntityFormBuilder.php
EntityFormTest.php in core/tests/Drupal/Tests/Core/Entity/EntityFormTest.php
ExposedFormPluginBase.php in core/modules/views/src/Plugin/views/exposed_form/ExposedFormPluginBase.php
FieldAttachOtherTest.php in core/modules/field/tests/src/Kernel/FieldAttachOtherTest.php
FieldItemListTest.php in core/tests/Drupal/Tests/Core/Field/FieldItemListTest.php
FieldWidgetConstraintValidatorTest.php in core/tests/Drupal/KernelTests/Core/Entity/FieldWidgetConstraintValidatorTest.php
FormAjaxResponseBuilderTest.php in core/tests/Drupal/Tests/Core/Form/FormAjaxResponseBuilderTest.php
FormAjaxSubscriberTest.php in core/tests/Drupal/Tests/Core/Form/EventSubscriber/FormAjaxSubscriberTest.php
FormBuilderTest.php in core/tests/Drupal/Tests/Core/Form/FormBuilderTest.php
Contains \Drupal\Tests\Core\Form\FormBuilderTest.
FormCacheTest.php in core/tests/Drupal/KernelTests/Core/Form/FormCacheTest.php
FormCacheTest.php in core/tests/Drupal/Tests/Core/Form/FormCacheTest.php
FormController.php in core/lib/Drupal/Core/Controller/FormController.php
FormDefaultHandlersTest.php in core/tests/Drupal/KernelTests/Core/Form/FormDefaultHandlersTest.php
FormElementInlineErrorTest.php in core/modules/inline_form_errors/tests/src/Kernel/FormElementInlineErrorTest.php
FormElementMaxlengthTest.php in core/modules/system/tests/src/Kernel/Form/FormElementMaxlengthTest.php
FormErrorHandlerTest.php in core/tests/Drupal/Tests/Core/Form/FormErrorHandlerTest.php
FormErrorHandlerTest.php in core/modules/inline_form_errors/tests/src/Unit/FormErrorHandlerTest.php
FormStateTest.php in core/tests/Drupal/Tests/Core/Form/FormStateTest.php
Contains \Drupal\Tests\Core\Form\FormStateTest.
FormSubmitterTest.php in core/tests/Drupal/Tests/Core/Form/FormSubmitterTest.php
FormTest.php in core/modules/field/tests/src/Functional/FormTest.php
FormTest.php in core/modules/system/tests/src/Functional/Form/FormTest.php
FormTestBase.php in core/tests/Drupal/Tests/Core/Form/FormTestBase.php
FormTestController.php in core/modules/system/tests/modules/form_test/src/Controller/FormTestController.php
FormValidationMessageOrderTest.php in core/tests/Drupal/KernelTests/Core/Form/FormValidationMessageOrderTest.php
FormValidatorTest.php in core/tests/Drupal/Tests/Core/Form/FormValidatorTest.php
ImageEffectsTest.php in core/modules/image/tests/src/Kernel/ImageEffectsTest.php
install.core.inc in core/includes/install.core.inc
API functions for installing Drupal.
LayoutTest.php in core/modules/layout_discovery/tests/src/Kernel/LayoutTest.php
MachineNameTest.php in core/tests/Drupal/Tests/Core/Render/Element/MachineNameTest.php
ManagedFileTest.php in core/modules/file/tests/src/Kernel/ManagedFileTest.php
MediaLibraryAddFormTest.php in core/modules/media_library/tests/src/Kernel/MediaLibraryAddFormTest.php
MediaLibraryUiBuilder.php in core/modules/media_library/src/MediaLibraryUiBuilder.php
MediaLibraryWidgetTest.php in core/modules/media_library/tests/src/Kernel/MediaLibraryWidgetTest.php
MediaSourceTest.php in core/modules/media/tests/src/Kernel/MediaSourceTest.php
MenuLinkDefaultFormTest.php in core/tests/Drupal/Tests/Core/Menu/MenuLinkDefaultFormTest.php
ModerationStateWidgetTest.php in core/modules/content_moderation/tests/src/Kernel/ModerationStateWidgetTest.php
ModuleTest.php in core/modules/views/tests/src/Kernel/ModuleTest.php
PathElementFormTest.php in core/tests/Drupal/KernelTests/Core/Element/PathElementFormTest.php
ProgrammaticTest.php in core/modules/system/tests/src/Kernel/Form/ProgrammaticTest.php
QueueSerializationTest.php in core/tests/Drupal/KernelTests/Core/Queue/QueueSerializationTest.php
QuickEditController.php in core/modules/quickedit/src/QuickEditController.php
RowEntityTest.php in core/modules/views/tests/src/Kernel/Plugin/RowEntityTest.php
SubformStateTest.php in core/tests/Drupal/Tests/Core/Form/SubformStateTest.php
TableSelectTest.php in core/tests/Drupal/Tests/Core/Render/Element/TableSelectTest.php
TestMultipleFormController.php in core/modules/block/tests/modules/block_test/src/Controller/TestMultipleFormController.php
TimezoneTest.php in core/tests/Drupal/KernelTests/Core/Datetime/Element/TimezoneTest.php
TriggeringElementProgrammedTest.php in core/tests/Drupal/KernelTests/Core/Form/TriggeringElementProgrammedTest.php
UserAccountFormFieldsTest.php in core/modules/user/tests/src/Kernel/UserAccountFormFieldsTest.php
ViewsFormBase.php in core/modules/views_ui/src/Form/Ajax/ViewsFormBase.php
views_ui.theme.inc in core/modules/views_ui/views_ui.theme.inc
Preprocessors and theme functions for the Views UI.
WeightTest.php in core/tests/Drupal/KernelTests/Core/Render/Element/WeightTest.php
WizardPluginBaseKernelTest.php in core/modules/views/tests/src/Kernel/Wizard/WizardPluginBaseKernelTest.php
WizardPluginBaseTest.php in core/modules/views/tests/src/Unit/WizardPluginBaseTest.php
WorkspaceIntegrationTest.php in core/modules/workspaces/tests/src/Kernel/WorkspaceIntegrationTest.php

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