12 files declare their use of PasswordInterface

EntityUser.php in core/modules/user/src/Plugin/migrate/destination/EntityUser.php
PasswordItemTest.php in core/tests/Drupal/KernelTests/Core/Field/FieldType/PasswordItemTest.php
PasswordVerifyTest.php in core/modules/phpass/tests/src/Unit/PasswordVerifyTest.php
PhpPasswordArgon2idIntegrationTest.php in core/tests/Drupal/KernelTests/Core/Password/PhpPasswordArgon2idIntegrationTest.php
PhpPasswordBcryptIntegrationTest.php in core/tests/Drupal/KernelTests/Core/Password/PhpPasswordBcryptIntegrationTest.php
PhpPasswordDefaultIntegrationTest.php in core/tests/Drupal/KernelTests/Core/Password/PhpPasswordDefaultIntegrationTest.php
PhpPasswordTest.php in core/tests/Drupal/Tests/Core/Password/PhpPasswordTest.php
PhpPasswordUnknownAlgorithmIntegrationTest.php in core/tests/Drupal/KernelTests/Core/Password/PhpPasswordUnknownAlgorithmIntegrationTest.php
UserAuth.php in core/modules/user/src/UserAuth.php
UserAuthentication.php in core/modules/user/src/UserAuthentication.php
UserAuthenticationTest.php in core/modules/user/tests/src/Unit/UserAuthenticationTest.php
UserAuthTest.php in core/modules/user/tests/src/Unit/UserAuthTest.php

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