diff --git a/tests/phpunit/tests/rest-api/rest-attachments-controller.php b/tests/phpunit/tests/rest-api/rest-attachments-controller.php
index 27519610e8..0f018b0118 100644
--- a/tests/phpunit/tests/rest-api/rest-attachments-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-attachments-controller.php
@@ -1678,6 +1678,16 @@ class WP_Test_REST_Attachments_Controller extends WP_Test_REST_Post_Type_Control
 		$wp_rest_additional_fields = array();
 	}
 
+	public function additional_field_get_callback( $object, $field_name ) {
+		return 123;
+	}
+
+	public function additional_field_update_callback( $value, $attachment ) {
+		if ( 'returnError' === $value ) {
+			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
+		}
+	}
+
 	public function test_search_item_by_filename() {
 		$id1 = self::factory()->attachment->create_object(
 			self::$test_file,
@@ -1706,16 +1716,6 @@ class WP_Test_REST_Attachments_Controller extends WP_Test_REST_Post_Type_Control
 		$this->assertSame( 'image/png', $data[0]['mime_type'] );
 	}
 
-	public function additional_field_get_callback( $object, $request ) {
-		return 123;
-	}
-
-	public function additional_field_update_callback( $value, $attachment ) {
-		if ( 'returnError' === $value ) {
-			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
-		}
-	}
-
 	public function test_links_exist() {
 
 		wp_set_current_user( self::$editor_id );
diff --git a/tests/phpunit/tests/rest-api/rest-autosaves-controller.php b/tests/phpunit/tests/rest-api/rest-autosaves-controller.php
index 2a7eacb8b9..bec3c1e578 100644
--- a/tests/phpunit/tests/rest-api/rest-autosaves-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-autosaves-controller.php
@@ -514,12 +514,12 @@ class WP_Test_REST_Autosaves_Controller extends WP_Test_REST_Post_Type_Controlle
 		$wp_rest_additional_fields = array();
 	}
 
-	public function additional_field_get_callback( $object ) {
-		return get_post_meta( $object['id'], 'my_custom_int', true );
+	public function additional_field_get_callback( $object, $field_name ) {
+		return get_post_meta( $object['id'], $field_name, true );
 	}
 
-	public function additional_field_update_callback( $value, $post ) {
-		update_post_meta( $post->ID, 'my_custom_int', $value );
+	public function additional_field_update_callback( $value, $post, $field_name ) {
+		update_post_meta( $post->ID, $field_name, $value );
 	}
 
 	protected function check_get_autosave_response( $response, $autosave ) {
diff --git a/tests/phpunit/tests/rest-api/rest-categories-controller.php b/tests/phpunit/tests/rest-api/rest-categories-controller.php
index 070dac5047..b83ee7b54c 100644
--- a/tests/phpunit/tests/rest-api/rest-categories-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-categories-controller.php
@@ -1180,7 +1180,7 @@ class WP_Test_REST_Categories_Controller extends WP_Test_REST_Controller_Testcas
 		$wp_rest_additional_fields = array();
 	}
 
-	public function additional_field_get_callback( $object, $request ) {
+	public function additional_field_get_callback( $object, $field_name ) {
 		return 123;
 	}
 
diff --git a/tests/phpunit/tests/rest-api/rest-comments-controller.php b/tests/phpunit/tests/rest-api/rest-comments-controller.php
index be8036e90b..35c71ac6f6 100644
--- a/tests/phpunit/tests/rest-api/rest-comments-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-comments-controller.php
@@ -3298,15 +3298,15 @@ class WP_Test_REST_Comments_Controller extends WP_Test_REST_Controller_Testcase
 		$wp_rest_additional_fields = array();
 	}
 
-	public function additional_field_get_callback( $object ) {
-		return get_comment_meta( $object['id'], 'my_custom_int', true );
+	public function additional_field_get_callback( $object, $field_name ) {
+		return get_comment_meta( $object['id'], $field_name, true );
 	}
 
-	public function additional_field_update_callback( $value, $comment ) {
+	public function additional_field_update_callback( $value, $comment, $field_name ) {
 		if ( 'returnError' === $value ) {
 			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
 		}
-		update_comment_meta( $comment->comment_ID, 'my_custom_int', $value );
+		update_comment_meta( $comment->comment_ID, $field_name, $value );
 	}
 
 	protected function check_comment_data( $data, $context, $links ) {
diff --git a/tests/phpunit/tests/rest-api/rest-posts-controller.php b/tests/phpunit/tests/rest-api/rest-posts-controller.php
index 4b66145d80..98e2e00790 100644
--- a/tests/phpunit/tests/rest-api/rest-posts-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-posts-controller.php
@@ -4586,15 +4586,15 @@ class WP_Test_REST_Posts_Controller extends WP_Test_REST_Post_Type_Controller_Te
 		$wp_rest_additional_fields = array();
 	}
 
-	public function additional_field_get_callback( $object ) {
-		return get_post_meta( $object['id'], 'my_custom_int', true );
+	public function additional_field_get_callback( $object, $field_name ) {
+		return get_post_meta( $object['id'], $field_name, true );
 	}
 
-	public function additional_field_update_callback( $value, $post ) {
+	public function additional_field_update_callback( $value, $post, $field_name ) {
 		if ( 'returnError' === $value ) {
 			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
 		}
-		update_post_meta( $post->ID, 'my_custom_int', $value );
+		update_post_meta( $post->ID, $field_name, $value );
 	}
 
 	public function test_publish_action_ldo_registered() {
diff --git a/tests/phpunit/tests/rest-api/rest-revisions-controller.php b/tests/phpunit/tests/rest-api/rest-revisions-controller.php
index c84624ca80..6997161281 100644
--- a/tests/phpunit/tests/rest-api/rest-revisions-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-revisions-controller.php
@@ -402,12 +402,12 @@ class WP_Test_REST_Revisions_Controller extends WP_Test_REST_Controller_Testcase
 		$wp_rest_additional_fields = array();
 	}
 
-	public function additional_field_get_callback( $object ) {
-		return get_post_meta( $object['id'], 'my_custom_int', true );
+	public function additional_field_get_callback( $object, $field_name ) {
+		return get_post_meta( $object['id'], $field_name, true );
 	}
 
-	public function additional_field_update_callback( $value, $post ) {
-		update_post_meta( $post->ID, 'my_custom_int', $value );
+	public function additional_field_update_callback( $value, $post, $field_name ) {
+		update_post_meta( $post->ID, $field_name, $value );
 	}
 
 	protected function check_get_revision_response( $response, $revision ) {
diff --git a/tests/phpunit/tests/rest-api/rest-tags-controller.php b/tests/phpunit/tests/rest-api/rest-tags-controller.php
index 945d97a304..6a8f29b7c1 100644
--- a/tests/phpunit/tests/rest-api/rest-tags-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-tags-controller.php
@@ -1324,6 +1324,16 @@ class WP_Test_REST_Tags_Controller extends WP_Test_REST_Controller_Testcase {
 		$wp_rest_additional_fields = array();
 	}
 
+	public function additional_field_get_callback( $object, $field_name ) {
+		return 123;
+	}
+
+	public function additional_field_update_callback( $value, $tag ) {
+		if ( 'returnError' === $value ) {
+			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
+		}
+	}
+
 	/**
 	 * @ticket 38504
 	 */
@@ -1396,16 +1406,6 @@ class WP_Test_REST_Tags_Controller extends WP_Test_REST_Controller_Testcase {
 		$this->assertArrayNotHasKey( $view_field, $data );
 	}
 
-	public function additional_field_get_callback( $object, $request ) {
-		return 123;
-	}
-
-	public function additional_field_update_callback( $value, $tag ) {
-		if ( 'returnError' === $value ) {
-			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
-		}
-	}
-
 	protected function check_get_taxonomy_terms_response( $response ) {
 		$this->assertSame( 200, $response->get_status() );
 		$data = $response->get_data();
diff --git a/tests/phpunit/tests/rest-api/rest-users-controller.php b/tests/phpunit/tests/rest-api/rest-users-controller.php
index 05e01a6e92..3a1c0965b9 100644
--- a/tests/phpunit/tests/rest-api/rest-users-controller.php
+++ b/tests/phpunit/tests/rest-api/rest-users-controller.php
@@ -2825,6 +2825,17 @@ class WP_Test_REST_Users_Controller extends WP_Test_REST_Controller_Testcase {
 		$wp_rest_additional_fields = array();
 	}
 
+	public function additional_field_get_callback( $object, $field_name ) {
+		return get_user_meta( $object['id'], $field_name, true );
+	}
+
+	public function additional_field_update_callback( $value, $user, $field_name ) {
+		if ( 'returnError' === $value ) {
+			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
+		}
+		update_user_meta( $user->ID, $field_name, $value );
+	}
+
 	/**
 	 * @ticket 39701
 	 * @group ms-required
@@ -3072,17 +3083,6 @@ class WP_Test_REST_Users_Controller extends WP_Test_REST_Controller_Testcase {
 		);
 	}
 
-	public function additional_field_get_callback( $object ) {
-		return get_user_meta( $object['id'], 'my_custom_int', true );
-	}
-
-	public function additional_field_update_callback( $value, $user ) {
-		if ( 'returnError' === $value ) {
-			return new WP_Error( 'rest_invalid_param', 'Testing an error.', array( 'status' => 400 ) );
-		}
-		update_user_meta( $user->ID, 'my_custom_int', $value );
-	}
-
 	protected function check_user_data( $user, $data, $context, $links ) {
 		$this->assertSame( $user->ID, $data['id'] );
 		$this->assertSame( $user->display_name, $data['name'] );