User:Tgr (WMF)/DifferenceEngine/test plan

High priority

 * display diff page by going into page history and using the "Compare selected revisions" button
 * should have title, headers (two blocks with links to revisions, undo/edit links, user etc), diff, the HTML view of the right-hand version - compare with a diff in production
 * should have warning below the headers iff the revisions are not direct neighbors
 * the actual diff rendering logic was not touched, no
 * test that the right revisions get diffed when giving the parameters in various ways (mostly the same code path - no need to check all details, just verify that the right revisions are diffed):
 * "cur" link in page history"
 * prev link in page history
 * test with left, right, both revision hidden from the user
 * create some multi-content revision (see below)
 * test diffs with multiple slots
 * test diff where some slot only exists on the left/right side
 * test multi-slot diff in mobile view (with MobileFrontend)
 * test multi-slot diff where main slot is Wikibase

Medium priority

 * test multi-content diff where some slot is not text (Wikibase? how do you create a content object?)

Low priority

 * test with left, right, both ID invalid (also with diff=prev/next when there is no prev/next revision)
 * test other diff engines (set  to ,   (needs the   vagrant module) (is there a way to test the external executable path?)
 * test revision selection when ids are swapped in the URL
 * test with left, right, both revision hidden when the user has permission to see it
 * test with left, right, both revision suppressed when the user does / does not have permission to see it

Creating test revisions
Set, use  , run something like