I would like to point out that pricing rule seems buggy and incomplete, after brief testing I manage to found 7 bugs related to pricing rule.
Details list at Google Sheet.
My environment are:
Setup: ERPNext Docker Debian on windows 10
ERPNext: v12.5.0 (version-12)
Frappe Framework: v12.3.0 (version-12)
Also here is my attempt to simplify pricing rule process.
(Nothing related to the bugs but I create it for my self to further understand how pricing rule works)
Thanks so much for this valuable contribution @pipech
Your workflow diagram and spreadsheet together are a big help to map and define all of the uses cases, functional gaps and actual versus expected result bugs.
These six pricing rule tests are an excellent basis to start that could be extended to the additional test case gaps you have identified.
frappe@ubuntu1804lts:~/frappe-bench$ find . -name ‘test_pricing_rule.py’ | xargs grep ‘def test’