Fix broken links in RichTextValue.output transformations

[thet]

Fix issue, where the RichTextValue.output was transforming relative to an ISite object. This broke relative links and for subsites also internal absolute links. Fixes: #7

Obsoletes branch: https://github.com/plone/plone.app.textfield/pull/thet-fix-issue7

@davisagli - Referring to the discussion in #7
Using output_relative_to isn't an option, as all templates are using just output. I don't really like the code for obtaining the context, but it was the only one I could come up with.

RFC, NOT READY TO MERGE!

No tests yet, as I want to discuss this issue first. I even have to reconstruct the testcases to provide examples, what was broken when. Wait for it.

[thet]

In plone.app.contenttypes I've seen code doing: <p tal:content="structure python:context.text.output_relative_to(view.context)"/> ( https://github.com/plone/plone.app.contenttypes/blob/master/plone/app/contenttypes/browser/templates/document.pt ) - which is awkward but the correct way.
Other code is using just output: ( https://github.com/plone/plone.app.contenttypes/blob/master/plone/app/contenttypes/browser/templates/newsitem.pt and other...).
I'd like to have this fixed for just calling textvalue/output, but my fix here is ugly because it relies on the existance of specific urls in the request var, needs traversing and does not work for indexing for example.
Maybe there is a better way to retrieve the current context?

It would be easier if we suggest people to use output_relative_to.

@pbauer any ideas on this?

[jensens]

whats the state here?

[thet]

Have to close this. The RichTextValue cannot access its context, so the RichTextValue's output method has to get passed the correct context:
Like: <p tal:content="structure python:context.text.output_relative_to(view.context)"/> ( https://github.com/plone/plone.app.contenttypes/blob/master/plone/app/contenttypes/browser/templates/document.pt )