BugLinkTargetMixin.linkBug() and unlinkBug() should take a user parameter rather than using LaunchBag

[Graham Binns]

At present, BugLinkTargetMixin.linkBug() and unlinkBug() don't take a user parameter, instead relying on the currently logged-in user when linking to bugs. This means that in tests we have to login() even when we shouldn't have to so as to avoid errors (since linking an object to a bug grants karma and you need a user to whom karma can be granted).

linkBug() and unlinkBug() should accept a user parameter and use this instead of the currently logged-in user. Also, they both call check_permission, which they shouldn't have to since the user should have been authorised before the call to [un]linkBug() is made.

[Francis J. Lacoste (flacoste)]

Right, linkBug() and unlinkBug() should accept a user parameter. The current behaviour is actually a violation of our coding policy where database code isn't supposed to use request-level context information. To that end, check_permission() is also verboten.

Unfortunately, that's not as easy to fix as you think, because linkBug() and unlinkBug() have to be protected at two places:

1) permission to access linkBug() and unlinkBug() on the target itself
2) the permission on the target object also needs to be checked.

Otherwise, a user who as access to a question can link to a private bug. Only the first permission can be assumed currently. The way to fix is described in bug #117980.

[Launchpad QA Bot (lpqabot)]

Fixed in stable r17774 (http://bazaar.launchpad.net/~launchpad-pqm/launchpad/stable/revision/17774) by a commit, but not testable.