9 files declare their use of StatementInterface

DatabaseLegacyTest.php in core/tests/Drupal/KernelTests/Core/Database/DatabaseLegacyTest.php
EmptyStatementTest.php in core/tests/Drupal/Tests/Core/Database/EmptyStatementTest.php
FetchTest.php in core/tests/Drupal/KernelTests/Core/Database/FetchTest.php
HelpSearch.php in core/modules/help_topics/src/Plugin/Search/HelpSearch.php
node.module in core/modules/node/node.module
The core module that allows content to be submitted to the site.
NodeSearch.php in core/modules/node/src/Plugin/Search/NodeSearch.php
PagerPluginBaseTest.php in core/modules/views/tests/src/Unit/Plugin/pager/PagerPluginBaseTest.php
Contains \Drupal\Tests\views\Unit\Plugin\pager\PagerPluginBaseTest.
SqlBaseTest.php in core/modules/migrate/tests/src/Kernel/SqlBaseTest.php
Contains \Drupal\Tests\migrate\Kernel\SqlBaseTest.
Statement.php in core/lib/Drupal/Core/Database/Driver/sqlite/Statement.php

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