Description:
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PharData::addEmptyDir() on a tar archive adds empty files instead of directories.




Reproduce code:
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$zip = new PharData('test.tar');
$zip = $zip->convertToData(Phar::TAR, Phar::NONE); // compression scheme does not affect the result.
// Phar::ZIP is not buggy, but you need to add a file to the empty directory to see this.
$zip->startBuffering();
$zip->addEmptyDir('test/');
// $zip->addFile('file', 'test/file'); // see (*)
$zip->stopBuffering();


Expected result:
----------------
test.tar.bz2 should contain 1 empty directory "test"


Actual result:
--------------
test.tar.bz2 contains 1 empty *file* "test"

(*) doing this will create the directory "test" automatically, so that the tar archive now contains both a file and a directory called "test", and becomes unextractable.