/**
  * @param callable $onProgress
  *
  * @return TombstoneIndex
  */
 public function getTombstones(callable $onProgress)
 {
     foreach ($this->files as $file) {
         $this->tombstoneExtractor->extractTombstones($file);
         $onProgress();
     }
     return $this->tombstoneExtractor->getTombstones();
 }
 /**
  * @param callable $onProgress
  *
  * @return TombstoneIndex
  */
 public function getTombstones(callable $onProgress)
 {
     foreach ($this->files as $file) {
         if ($this->ignoreErrors) {
             try {
                 $this->tombstoneExtractor->extractTombstones($file);
             } catch (\Exception $e) {
                 print "\nIgnore parse error: " . $e->getMessage() . "\n";
             }
         } else {
             $this->tombstoneExtractor->extractTombstones($file);
         }
         $onProgress();
     }
     return $this->tombstoneExtractor->getTombstones();
 }