We prevent to merge partner linked to more than one user (by raising an
exception) to avoid having multiple user pointing to the same partner as a
consequence of a merge.
We want to avoid this situation because it generates weird behaviors. As
res.user inherits from res.partner, having multiple user pointing to the same
partner makes the fields of that partner shared with all those users. This was
decided following the tentative to improve partner merge in website_slides
(odoo/odoo#114840), where we also noticed strange behavior like completing a
lesson with one user were adding karma to all the users linked to a same
partner.
We have also adapted WebsiteVisitorTests tests in website that were failing
because they were merging partners with more than one user: simply by merging
partners with only one user.
Task-3167160
closesodoo/odoo#125322
Signed-off-by: Stéphane Debauche (std) <std@odoo.com>
Pierre-Yves Dufays
169eaec793