Description:
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Is there any reason why we can't use Phar::setSignatureAlgorithm() after Phar::setStub()?

https://github.com/defuse/php-encryption/pull/139

If there's a reason this shouldn't allowed, could the documentation please be updated to reflect this decision?

If this is a bug, it's breaking our ability to publish signed a .phar for defuse/php-encryption


Test script:
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https://raw.githubusercontent.com/paragonie/php-encryption/29dc5e866bb08dac38fef721f3356f2e2fea76c3/other/build_phar.php

Expected result:
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Silent success, but if I do this:

$phar = new \Phar(dirname(__DIR__).'/dist/defuse-crypto.phar');
$signature = $phar->getSignature();
var_dump($signature);

...it shouldn't say its "hash_type" is "SHA-1"

Actual result:
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PHP Fatal error:  Uncaught exception 'PharException' with message 'unable to copy stub of old phar to new phar "/var/www/defuse/php-encryption/dist/defuse-crypto.phar"' in /var/www/defuse/php-encryption/other/build_phar.php:37
Stack trace:
#0 /var/www/defuse/php-encryption/other/build_phar.php(37): Phar->setSignatureAlgorithm(16, '-----BEGIN PRIV...')
#1 {main}
  thrown in /var/www/defuse/php-encryption/other/build_phar.php on line 37