14 uses of DRUPAL_REQUIRED

CommentForm::actions in core/modules/comment/src/CommentForm.php
CommentInterfaceTest::testCommentInterface in core/modules/comment/tests/src/Functional/CommentInterfaceTest.php
Tests the comment interface.
CommentNonNodeTest::postComment in core/modules/comment/tests/src/Functional/CommentNonNodeTest.php
Posts a comment.
CommentTestBase::postComment in core/modules/comment/tests/src/Functional/CommentTestBase.php
Posts a comment.
CommentTestBase::setCommentPreview in core/modules/comment/tests/src/Functional/CommentTestBase.php
Sets the value governing the previewing mode for the comment form.
LinkField::alterFieldInstanceMigration in core/modules/link/src/Plugin/migrate/field/d7/LinkField.php
LinkFieldTest::doTestLinkTitle in core/modules/link/tests/src/Functional/LinkFieldTest.php
Tests the link title settings of a link field.
LinkFieldTest::testAlterFieldInstanceMigration in core/modules/link/tests/src/Kernel/Plugin/migrate/field/d7/LinkFieldTest.php
@covers ::alterFieldInstanceMigration
LinkItem::generateSampleValue in core/modules/link/src/Plugin/Field/FieldType/LinkItem.php
LinkWidget::formElement in core/modules/link/src/Plugin/Field/FieldWidget/LinkWidget.php
MigrateFieldInstanceTest::testFieldInstances in core/modules/field/tests/src/Kernel/Migrate/d7/MigrateFieldInstanceTest.php
Tests migrating D7 field instances to field_config entities.
NodeForm::actions in core/modules/node/src/NodeForm.php
NodeTypeValidationTest::testPreviewModeValidation in core/modules/node/tests/src/Kernel/NodeTypeValidationTest.php
Tests that a node type's preview mode is constrained to certain values.
PagePreviewTest::testPagePreview in core/modules/node/tests/src/Functional/PagePreviewTest.php
Checks the node preview functionality.

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