Description:
------------
The finally block of a Generator that is decorated with or nested in another Generator is never called. This behavior is of course true for multiple decoration or nesting levels.

Using a finally block for clean-up in case a Generator is aborted is the official and only way of doing so. It is also recommended in the initial RFC:

https://wiki.php.net/rfc/generators#closing_a_generator

Please see attached test script as well as expected and actual result.

Test script:
---------------
#!/usr/bin/env php
<?php

function generator() {
	try {
		while (true) {
			yield 'Hello';
		}
	}
	finally {
		echo "Generator Clean-up\n";
	}
}

function generator_decoration() {
	try {
		foreach (generator() as $word) {
			yield $word . " World!\n";
		}
	}
	finally {
		echo "Decorator Clean-up\n";
	}
}

foreach (generator_decoration() as $sentence) {
	echo $sentence . "Break\n";
	break;
}

echo "Shutdown\n";


Expected result:
----------------
Hello World!
Break
Decorator Clean-up
Generator Clean-up
Shutdown

Actual result:
--------------
Hello World!
Break
Decorator Clean-up
Shutdown
Generator Clean-up

Workaround:
----------------

In case a frustrated user is finding this bug report. There is a possible workaround that works in all PHP versions that support Generators via a signal that is being sent to the Generator. Please have a look at the following example that makes use of it.

#!/usr/bin/env php
<?php

const GENERATOR_BREAK = 'PHP_GENERATOR_BREAK';

function generator() {
	try {
		while (true) {
			if ((yield 'Hello') === GENERATOR_BREAK) {
				break;
			}
		}
	}
	finally {
		echo "Generator Clean-up\n";
	}
}

function generator_decoration() {
	$generator = generator();
	try {
		foreach ($generator as $word) {
			yield $word . " World!\n";
		}
	}
	finally {
		echo "Decorator Clean-up\n";
		$generator->send(GENERATOR_BREAK);
	}
}

foreach (generator_decoration() as $sentence) {
	echo $sentence . "Break\n";
	break;
}

echo "Shutdown\n";