Ticket #34976: 34976.2.diff

src/wp-admin/includes/class-wp-filesystem-ftpext.php

@@ -322 +322 @@
                 if ( !empty($filelist) )
                         foreach ( $filelist as $delete_file )
                                 $this->delete( trailingslashit($file) . $delete_file['name'], $recursive, $delete_file['type'] );
                 return @ftp_rmdir($this->link, $file);
         }
 
         /**
          * @access public
          *
          * @param string $file
          * @return bool
          */
         public function exists( $file ) {
                 $path = dirname( $file );
                 $filename = basename( $file );
+                $hidden = ( '.' === substr( $filename, 0, 1 ) );
 
-                $file_list = @ftp_nlist( $this->link, '-a ' . $path );
+                // Attempt an NLST, conditionally including -a if it's a hidden file
+                $file_list = @ftp_nlist( $this->link, ( $hidden ? '-a ' : '' ) . $path );
                 if ( $file_list ) {
                         $file_list = array_map( 'basename', $file_list );
+                        if ( in_array( $filename, $file_list ) ) {
+                                return true;
+                        }
                 }
 
-                return $file_list && in_array( $filename, $file_list );
+                // For hidden files, perform a few extra checks for compat.
+                if ( $hidden ) {
+                        // Try LIST -a
+                        $file_list = @ftp_rawlist( $this->link, '-a ' . $file );
+                        if ( empty( $file_list ) && $this->is_dir( $file ) ) {
+                                // File is an empty directory.
+                                return true;
+                        }
+                        // Empty list = no file, so invert.
+                        if ( ! empty( $file_list ) ) {
+                                return true;
+                        }
+
+                        // Try NLIST without -a, some servers will return hidden files this way which don't get caught by LIST -a
+                        $file_list = @ftp_nlist( $this->link, $path );
+                        if ( $file_list ) {
+                                $file_list = array_map( 'basename', $file_list );
+                                if ( in_array( $filename, $file_list ) ) {
+                                        return true;
+                                }
+                        }
+                }
+
+                return false;
         }
 
         /**
          * @access public
          *
          * @param string $file
          * @return bool
          */
         public function is_file($file) {
                 return $this->exists($file) && !$this->is_dir($file);
         }
 
         /**
          * @access public
          *