39 files declare their use of FormInterface
- ActionsTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Render/ Element/ ActionsTest.php  - AjaxFormBlock.php in core/
modules/ system/ tests/ modules/ ajax_forms_test/ src/ Plugin/ Block/ AjaxFormBlock.php  - AjaxTestFocusFirstForm.php in core/
modules/ system/ tests/ modules/ ajax_test/ src/ Form/ AjaxTestFocusFirstForm.php  - AjaxTestMessageCommandForm.php in core/
modules/ system/ tests/ modules/ ajax_test/ src/ Form/ AjaxTestMessageCommandForm.php  - BlockListBuilder.php in core/
modules/ block/ src/ BlockListBuilder.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  - DraggableListBuilder.php in core/
lib/ Drupal/ Core/ Config/ Entity/ DraggableListBuilder.php  - ElementsFieldsetTest.php in core/
modules/ system/ tests/ src/ Kernel/ Form/ ElementsFieldsetTest.php  - EntityAutocompleteElementFormTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Entity/ Element/ EntityAutocompleteElementFormTest.php  - EntityResolverManagerTest.php in core/
tests/ Drupal/ Tests/ Core/ Entity/ EntityResolverManagerTest.php  - Contains \Drupal\Tests\Core\Entity\EntityResolverManagerTest.
 - EntityTypeInfo.php in core/
modules/ content_moderation/ src/ EntityTypeInfo.php  - ExternalFormUrlTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Form/ ExternalFormUrlTest.php  - FileTestForm.php in core/
modules/ file/ tests/ file_test/ src/ Form/ FileTestForm.php  - FormActionXssTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Form/ FormActionXssTest.php  - FormBuilderTest.php in core/
tests/ Drupal/ Tests/ Core/ Form/ FormBuilderTest.php  - Contains \Drupal\Tests\Core\Form\FormBuilderTest.
 - FormController.php in core/
modules/ system/ tests/ modules/ condition_test/ src/ FormController.php  - FormDefaultHandlersTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Form/ FormDefaultHandlersTest.php  - FormElementMaxlengthTest.php in core/
modules/ system/ tests/ src/ Kernel/ Form/ FormElementMaxlengthTest.php  - FormStateDecoratorBaseTest.php in core/
tests/ Drupal/ Tests/ Core/ Form/ FormStateDecoratorBaseTest.php  - FormStateTest.php in core/
tests/ Drupal/ Tests/ Core/ Form/ FormStateTest.php  - Contains \Drupal\Tests\Core\Form\FormStateTest.
 - FormTestBase.php in core/
tests/ Drupal/ Tests/ Core/ Form/ FormTestBase.php  - FormValidationMessageOrderTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Form/ FormValidationMessageOrderTest.php  - MachineNameTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Render/ Element/ MachineNameTest.php  - ManagedFileTest.php in core/
modules/ file/ tests/ src/ Kernel/ ManagedFileTest.php  - PathElementFormTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Element/ PathElementFormTest.php  - QueueSerializationTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Queue/ QueueSerializationTest.php  - SearchPageListBuilder.php in core/
modules/ search/ src/ SearchPageListBuilder.php  - TestFormApiFormBlock.php in core/
modules/ layout_builder/ tests/ modules/ layout_builder_form_block_test/ src/ Plugin/ Block/ TestFormApiFormBlock.php  - TextFormatElementFormTest.php in core/
modules/ filter/ tests/ src/ Kernel/ TextFormatElementFormTest.php  - TimezoneTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Datetime/ Element/ TimezoneTest.php  - TriggeringElementProgrammedTest.php in core/
tests/ Drupal/ KernelTests/ Core/ Form/ TriggeringElementProgrammedTest.php  - ViewsForm.php in core/
modules/ views/ src/ Form/ ViewsForm.php  - ViewsFormInterface.php in core/
modules/ views_ui/ src/ Form/ Ajax/ ViewsFormInterface.php  - ViewsFormMainForm.php in core/
modules/ views/ src/ Form/ ViewsFormMainForm.php  - ViewsTestDataErrorForm.php in core/
modules/ views/ tests/ modules/ views_test_data/ src/ Form/ ViewsTestDataErrorForm.php  - WorkspaceFormInterface.php in core/
modules/ workspaces/ src/ Form/ WorkspaceFormInterface.php  
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