Description:
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I just realized that phardata.compress removes same name files in tar archives.

I have multiple tar archives that contains multiple instances of files with the same name and when using the code below only the first occurrence of the file is preserved.

Test script:
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<?php
  $p = new PharData('tarFile.tar',0);
  $p->compress(Phar::GZ);
?>

Expected result:
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The expected result is to preserve all files in the archive and just compress it.

Actual result:
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Only first file (with the same name) is preserved.