We have a method for retrieving user identity fields that current user can see in the given context:

get_extra_user_fields()

However we do not have a method that returns what user name fields current user can see in the given context. In some places in code we use something like this:

order_in_string(get_all_user_name_fields(), $nameformat);

// $nameformat is calculated from $CFG->fullnamedisplay and $CFG->alternativefullnameformat 

// based on capability to view full names in the current context

Where we need this new method:

• Displaying the header with possible sort fields in the tables listing users (this is part of tablelib)
• Exporting reports where we need one line per user - we do not want to put fullname() in one cell of the export table, we want to have firstname, lastname, etc. as separate columns

To mention that there are some interesting methods in user_picture class but not quite what we need here