apply_filters( 'pre_wp_unique_filename_file_list', array|null $files, string $dir, string $filename )

2702			 *2703			 * @param array|null $files    The list of files to use for filename comparisons.2704			 *                             Default null (to retrieve the list from the filesystem).2705			 * @param string     $dir      The directory for the new file.2706			 * @param string     $filename The proposed filename for the new file.2707			 */2708			$files = apply_filters( 'pre_wp_unique_filename_file_list', null, $dir, $filename );2709 2710			if ( null === $files ) {2711				// List of all files and directories contained in $dir.2712				$files = @scandir( $dir );2713			}2714