Fix NULL being added to ParserContext classes

[erikwiffin]

Fixes bug referenced by ezzatron in https://github.com/FriendsOfPHP/Sami/issues/99#issuecomment-57895131. NULL was being added to the ParserContext classes array because of a complicated chain of events in PHP-Parser that resulted in leaveClass getting called without a matching enterClass. This doesn't fix the root cause, but it does allow for filtering out classes (ie. if SymfonyFilter is used).

[GrahamCampbell]

We need an extra blank line following this closing brace.

[aik099]

This doesn't fix the root cause, but it does allow for filtering out classes (ie. if SymfonyFilter is used).

I'd prefer a fix for a root cause considering that it's unlikely that PHP file was tokenized wrong.

[erikwiffin]

I looked into it a bit more, and this might actually be the best possible fix. The problem stems from https://github.com/nikic/PHP-Parser/blob/v1.0.2/lib/PhpParser/NodeTraverser.php and the traverseArray function. First, it loops through each node and calls $visitor->enterNode($node) on them. That makes it's way to Sami/Parser/NodeVisitor.php and the addClassOrInterface function. If a class is to be filtered out, $this->context->enterClass($class); (line 132) is never called. Since PhpParser doesn't care that you want to filter out the class, it happily continues on to call $visitor->leaveNode($node);.

It looks to me like unless you're willing to completely change how filtering classes works, isset($this->class) is going to need to be called somewhere, and leaveClass makes the most sense to me.

[aik099]

Better to check explicitly for null, e.g. null === $this->class.

[aik099]

@erikwiffin , I've looked at current code I now agree with you that check you've made is the right one. So if nobody entered class, then leaving non-entered class should be ignored as well.

[fabpot]

Thank you @erikwiffin.