Caching in syntax plugin is broken

[michitux]

The pagelist syntax plugin currently fetches all information like page existence or title in the handler. Even though the plugin writes metadata that expires the renderer cache when a page is created or deleted this is of no use as this does not expire the handler cache.

• Information like page existence or title should be fetched in the render function which should resolve parts of the problem.

Another problem is that when more columns like the description or tags are displayed that

• a) they should be updated when the referenced page is updated and
• b) they should not be displayed when the page is inaccessible by the current user.

This could be solved by a cache handler similar to the one that is used by the include plugin.

Note that the whole issue only affects the pagelist syntax and not the usage of this plugin as helper plugin which is probably how most people use this plugin.

[Klap-in]

The title in the handler is parsed from the input text in the pagelist syntax, so fine to cache. The existence is moved to the render() by #61.

Expiring by changed referred pages is probably not yet fixed.