Our versioning works on databse table level, this leads to situations that we save an article with custom fields but the CF are not included in the history. This is unexpected from a user perspective. This PR starts to change this behaviour so that releated information are also saved.

Summary of Changes

I have added an interface VersionableModelInterface, if a model implements this interface then in AdminModel the save of the histroy data is done in the save method (calls saveHistory) of the Model. This is the first step and we have now the data with releated information in the history table.

If you want to restore a version then in loadHistory (VersionableModelTrait) set the data from the history table as session data and loadForm use this data when you edit an item.

It works for CF so far. At the moment not for Tags (tags is a pain, we might change more on tags for 6 so I haven't looked into the details why not).

This is a b/c break and I don't know how many are affected but I think that it can't be too much hassle and what we get when we finish this is worth the work for extensions developers.

• Look into tags
• Extend to other core items where we are using versions (Banner, Banner Client, newfeeds, Categories Tags).
• Remove behaviour plugin
• Fix tests

Testing Instructions

It is only done for Articles and Contacts!

• Create some custom fields
• Create an article and save some versions of it
• Restore versions back and force

Actual result BEFORE applying this Pull Request

Custom fields have always the last saved value

Expected result AFTER applying this Pull Request

Custom fields have the value from the saved version

Link to documentations

Documentation will be provided at a later stage.

Please select:

• Documentation link for docs.joomla.org:

• No documentation changes for docs.joomla.org needed

• Pull Request link for manual.joomla.org:

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