132 files declare their use of FieldDefinitionInterface

AggregatorTitleFormatter.php in core/modules/aggregator/src/Plugin/Field/FieldFormatter/AggregatorTitleFormatter.php
AuthorFormatter.php in core/modules/user/src/Plugin/Field/FieldFormatter/AuthorFormatter.php
AuthorNameFormatter.php in core/modules/comment/src/Plugin/Field/FieldFormatter/AuthorNameFormatter.php
BaseFieldFileFormatterBase.php in core/modules/file/src/Plugin/Field/FieldFormatter/BaseFieldFileFormatterBase.php
BooleanItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/BooleanItem.php
CommentAccessControlHandler.php in core/modules/comment/src/CommentAccessControlHandler.php
CommentDefaultFormatter.php in core/modules/comment/src/Plugin/Field/FieldFormatter/CommentDefaultFormatter.php
CommentItem.php in core/modules/comment/src/Plugin/Field/FieldType/CommentItem.php
CommentPermalinkFormatter.php in core/modules/comment/src/Plugin/Field/FieldFormatter/CommentPermalinkFormatter.php
ConfigFieldDefinitionTest.php in core/modules/field/tests/src/Kernel/ConfigFieldDefinitionTest.php
ContentEntityNullStorage.php in core/lib/Drupal/Core/Entity/ContentEntityNullStorage.php
ContentEntityStorageBase.php in core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
ContentModerationStateFormatter.php in core/modules/content_moderation/src/Plugin/Field/FieldFormatter/ContentModerationStateFormatter.php
ContentTranslationSynchronizedFieldsConstraintValidator.php in core/modules/content_translation/src/Plugin/Validation/Constraint/ContentTranslationSynchronizedFieldsConstraintValidator.php
content_moderation.module in core/modules/content_moderation/content_moderation.module
Contains content_moderation.module.
content_translation.admin.inc in core/modules/content_translation/content_translation.admin.inc
The content translation administration forms.
DateRangeDefaultWidget.php in core/modules/datetime_range/src/Plugin/Field/FieldWidget/DateRangeDefaultWidget.php
DateRangeFieldItemList.php in core/modules/datetime_range/src/Plugin/Field/FieldType/DateRangeFieldItemList.php
DateRangeItem.php in core/modules/datetime_range/src/Plugin/Field/FieldType/DateRangeItem.php
DateTimeDefaultWidget.php in core/modules/datetime/src/Plugin/Field/FieldWidget/DateTimeDefaultWidget.php
DateTimeFieldItemList.php in core/modules/datetime/src/Plugin/Field/FieldType/DateTimeFieldItemList.php
DateTimeFormatterBase.php in core/modules/datetime/src/Plugin/Field/FieldFormatter/DateTimeFormatterBase.php
DateTimeIso8601NormalizerTest.php in core/modules/serialization/tests/src/Unit/Normalizer/DateTimeIso8601NormalizerTest.php
DateTimeItem.php in core/modules/datetime/src/Plugin/Field/FieldType/DateTimeItem.php
DecimalItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/DecimalItem.php
editor.module in core/modules/editor/editor.module
Adds bindings for client-side "text editors" to text formats.
EmailItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EmailItem.php
EntityAccessControlHandler.php in core/lib/Drupal/Core/Entity/EntityAccessControlHandler.php
EntityAccessControlHandlerInterface.php in core/lib/Drupal/Core/Entity/EntityAccessControlHandlerInterface.php
EntityDisplayBase.php in core/lib/Drupal/Core/Entity/EntityDisplayBase.php
EntityDisplayFormBase.php in core/modules/field_ui/src/Form/EntityDisplayFormBase.php
EntityFieldManagerTest.php in core/tests/Drupal/Tests/Core/Entity/EntityFieldManagerTest.php
Contains \Drupal\Tests\Core\Entity\EntityFieldManagerTest.
EntityFieldTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityFieldTest.php
EntityFormDisplayEditForm.php in core/modules/field_ui/src/Form/EntityFormDisplayEditForm.php
EntityReferenceEntityFormatter.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/EntityReferenceEntityFormatter.php
EntityReferenceFieldItemNormalizerTest.php in core/modules/serialization/tests/src/Unit/Normalizer/EntityReferenceFieldItemNormalizerTest.php
EntityReferenceItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/EntityReferenceItem.php
EntityReferenceTaxonomyTermRssFormatter.php in core/modules/taxonomy/src/Plugin/Field/FieldFormatter/EntityReferenceTaxonomyTermRssFormatter.php
EntityResource.php in core/modules/jsonapi/src/Controller/EntityResource.php
EntityTypedDataDefinitionTest.php in core/tests/Drupal/KernelTests/Core/Entity/EntityTypedDataDefinitionTest.php
EntityViewDisplayEditForm.php in core/modules/field_ui/src/Form/EntityViewDisplayEditForm.php
EntityViewsData.php in core/modules/views/src/EntityViewsData.php
entity_test.module in core/modules/system/tests/modules/entity_test/entity_test.module
Test module for the entity API providing several entity types for testing.
field.purge.inc in core/modules/field/field.purge.inc
Provides support for field data purge after mass deletion.
FieldableEntityStorageInterface.php in core/lib/Drupal/Core/Entity/FieldableEntityStorageInterface.php
FieldBlock.php in core/modules/layout_builder/src/Plugin/Block/FieldBlock.php
FieldBlockTest.php in core/modules/layout_builder/tests/src/Kernel/FieldBlockTest.php
FieldConfigEntityUnitTest.php in core/modules/field/tests/src/Unit/FieldConfigEntityUnitTest.php
Contains \Drupal\Tests\field\Unit\FieldConfigEntityUnitTest.
FieldConfigInterface.php in core/modules/field/src/FieldConfigInterface.php
FieldDefinitionListenerTest.php in core/tests/Drupal/Tests/Core/Field/FieldDefinitionListenerTest.php
FieldItemListTest.php in core/tests/Drupal/Tests/Core/Field/FieldItemListTest.php
FieldLayoutBuilder.php in core/modules/field_layout/src/FieldLayoutBuilder.php
FieldLayoutBuilderTest.php in core/modules/field_layout/tests/src/Unit/FieldLayoutBuilderTest.php
FieldNormalizer.php in core/modules/jsonapi/src/Normalizer/FieldNormalizer.php
FieldTranslationSynchronizer.php in core/modules/content_translation/src/FieldTranslationSynchronizer.php
FieldTranslationSynchronizerInterface.php in core/modules/content_translation/src/FieldTranslationSynchronizerInterface.php
field_test.field.inc in core/modules/field/tests/modules/field_test/field_test.field.inc
Defines a field type and its formatters and widgets.
field_test_boolean_access_denied.module in core/modules/field/tests/modules/field_test_boolean_access_denied/field_test_boolean_access_denied.module
Module for testing denying access to boolean fields.
field_third_party_test.module in core/modules/field/tests/modules/field_third_party_test/field_third_party_test.module
Test module.
file.field.inc in core/modules/file/file.field.inc
Field module functionality for the File module.
file.module in core/modules/file/file.module
Defines a "managed_file" Form API field and a "file" field for Field module.
FileAccessControlHandler.php in core/modules/file/src/FileAccessControlHandler.php
FileExtensionFormatter.php in core/modules/file/src/Plugin/Field/FieldFormatter/FileExtensionFormatter.php
FileItem.php in core/modules/file/src/Plugin/Field/FieldType/FileItem.php
FileMediaFormatterBase.php in core/modules/file/src/Plugin/Field/FieldFormatter/FileMediaFormatterBase.php
FilemimeFormatter.php in core/modules/file/src/Plugin/Field/FieldFormatter/FilemimeFormatter.php
FileSize.php in core/modules/file/src/Plugin/Field/FieldFormatter/FileSize.php
FileUpload.php in core/modules/jsonapi/src/Controller/FileUpload.php
FileUploadResource.php in core/modules/file/src/Plugin/rest/resource/FileUploadResource.php
FileUriFormatter.php in core/modules/file/src/Plugin/Field/FieldFormatter/FileUriFormatter.php
FileWidget.php in core/modules/file/src/Plugin/Field/FieldWidget/FileWidget.php
FloatItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/FloatItem.php
ImageFormatter.php in core/modules/image/src/Plugin/Field/FieldFormatter/ImageFormatter.php
ImageItem.php in core/modules/image/src/Plugin/Field/FieldType/ImageItem.php
ImageUrlFormatter.php in core/modules/image/src/Plugin/Field/FieldFormatter/ImageUrlFormatter.php
ImageWidget.php in core/modules/image/src/Plugin/Field/FieldWidget/ImageWidget.php
image_access_test_hidden.module in core/modules/image/tests/modules/image_access_test_hidden/image_access_test_hidden.module
Image field access for hidden fields.
IntegerItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/IntegerItem.php
jsonapi_test_field_access.module in core/modules/jsonapi/tests/modules/jsonapi_test_field_access/jsonapi_test_field_access.module
Contains hook implementations for testing the JSON:API module.
jsonapi_test_field_filter_access.module in core/modules/jsonapi/tests/modules/jsonapi_test_field_filter_access/jsonapi_test_field_filter_access.module
Contains hook implementations for testing the JSON:API module.
language.module in core/modules/language/language.module
Add language handling functionality to Drupal.
LanguageFormatter.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/LanguageFormatter.php
LanguageItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/LanguageItem.php
language_entity_field_access_test.module in core/modules/language/tests/language_entity_field_access_test/language_entity_field_access_test.module
Hook implementations for language_entity_field_access_test.
LayoutBuilderDefaultValuesTest.php in core/modules/layout_builder/tests/src/Functional/LayoutBuilderDefaultValuesTest.php
LayoutBuilderEntityViewDisplayForm.php in core/modules/layout_builder/src/Form/LayoutBuilderEntityViewDisplayForm.php
LayoutSectionItem.php in core/modules/layout_builder/src/Plugin/Field/FieldType/LayoutSectionItem.php
LinkFormatter.php in core/modules/link/src/Plugin/Field/FieldFormatter/LinkFormatter.php
LinkFormatterTest.php in core/modules/link/tests/src/Unit/LinkFormatterTest.php
LinkItem.php in core/modules/link/src/Plugin/Field/FieldType/LinkItem.php
ListItemBase.php in core/modules/options/src/Plugin/Field/FieldType/ListItemBase.php
MediaLibraryWidget.php in core/modules/media_library/src/Plugin/Field/FieldWidget/MediaLibraryWidget.php
MediaThumbnailFormatter.php in core/modules/media/src/Plugin/Field/FieldFormatter/MediaThumbnailFormatter.php
media_library_test.module in core/modules/media_library/tests/modules/media_library_test/media_library_test.module
Contains hook implementations for the media_library_test module.
ModerationStateWidget.php in core/modules/content_moderation/src/Plugin/Field/FieldWidget/ModerationStateWidget.php
Node.php in core/modules/node/src/Plugin/views/wizard/Node.php
NodeAccessControlHandler.php in core/modules/node/src/NodeAccessControlHandler.php
OEmbedFormatter.php in core/modules/media/src/Plugin/Field/FieldFormatter/OEmbedFormatter.php
OEmbedWidget.php in core/modules/media/src/Plugin/Field/FieldWidget/OEmbedWidget.php
OptionsWidgetBase.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldWidget/OptionsWidgetBase.php
PathItem.php in core/modules/path/src/Plugin/Field/FieldType/PathItem.php
ResourceTestBase.php in core/modules/jsonapi/tests/src/Functional/ResourceTestBase.php
ResourceTypeRepository.php in core/modules/jsonapi/src/ResourceType/ResourceTypeRepository.php
ResponsiveImageFormatter.php in core/modules/responsive_image/src/Plugin/Field/FieldFormatter/ResponsiveImageFormatter.php
rest_test.module in core/modules/rest/tests/modules/rest_test/rest_test.module
Contains hook implementations for testing REST module.
SelectionPluginManager.php in core/lib/Drupal/Core/Entity/EntityReferenceSelection/SelectionPluginManager.php
SelectionPluginManagerInterface.php in core/lib/Drupal/Core/Entity/EntityReferenceSelection/SelectionPluginManagerInterface.php
SqlContentEntityStorage.php in core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php
StatusItem.php in core/modules/user/src/StatusItem.php
StringFormatter.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/StringFormatter.php
StringItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/StringItem.php
StringLongItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/StringLongItem.php
TelephoneItem.php in core/modules/telephone/src/Plugin/Field/FieldType/TelephoneItem.php
TemporaryJsonapiFileFieldUploader.php in core/modules/jsonapi/src/Controller/TemporaryJsonapiFileFieldUploader.php
TestBaseFieldDefinitionInterface.php in core/tests/Drupal/Tests/Core/Field/TestBaseFieldDefinitionInterface.php
TestFieldApplicableFormatter.php in core/modules/field/tests/modules/field_test/src/Plugin/Field/FieldFormatter/TestFieldApplicableFormatter.php
TestFieldWidgetMultiple.php in core/modules/field/tests/modules/field_test/src/Plugin/Field/FieldWidget/TestFieldWidgetMultiple.php
TestItemWithDependencies.php in core/modules/field/tests/modules/field_test/src/Plugin/Field/FieldType/TestItemWithDependencies.php
TextItemBase.php in core/modules/text/src/Plugin/Field/FieldType/TextItemBase.php
TimestampAgoFormatter.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampAgoFormatter.php
TimestampFormatter.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldFormatter/TimestampFormatter.php
TimestampItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/TimestampItem.php
TimestampItemNormalizerTest.php in core/modules/serialization/tests/src/Unit/Normalizer/TimestampItemNormalizerTest.php
TimeZoneItem.php in core/modules/user/src/TimeZoneItem.php
UriItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/UriItem.php
UserAccessControlHandler.php in core/modules/user/src/UserAccessControlHandler.php
UserMailRequiredValidatorTest.php in core/modules/user/tests/src/Unit/Plugin/Validation/Constraint/UserMailRequiredValidatorTest.php
UserNameFormatter.php in core/modules/user/src/Plugin/Field/FieldFormatter/UserNameFormatter.php
UserNameItem.php in core/modules/user/src/UserNameItem.php
user_access_test.module in core/modules/user/tests/modules/user_access_test/user_access_test.module
Dummy module implementing hook_user_access() to test if entity access is respected.
UuidItem.php in core/lib/Drupal/Core/Field/Plugin/Field/FieldType/UuidItem.php
views_entity_test.module in core/modules/views/tests/modules/views_entity_test/views_entity_test.module
Contains main module functionality.

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