[Releasing] Avoiding platform test coverage regressions

[Jani Heikkinen]

Hi!

I totally agree with you that missing platforms should block the release. I would be even tighter, we should get all new platforms we are planning to support in before feature freeze. But lately it has been really hard to get new platforms in and that's why we have accepted the situation where missing platform hasn't been the release blocker. 

And that is one of most important things to be fixed. We need to get new platforms in ci much easier that it is now. I have seen us fighting to get new platforms in several months. And that should be only few hours work. It seems that it is really hard to get all tests passing at same time for that new platform. We try to get new platform in & find some test failing. Failures are fixed and new try... Argh, some other test are now failing ;) And test are fixed and new test are failing... All that has prevented us to get stuff in. So we need to find a way to get platforms in easier or then block other development until failed test are fixed & new platform is in.

br,
Jani

________________________________________
From: Releasing <releasing-bounces+jani.heikkinen=qt.io at qt-project.org> on behalf of Simon Hausmann <Simon.Hausmann at qt.io>
Sent: Wednesday, January 25, 2017 2:31 PM
To: releasing at qt-project.org
Subject: [Releasing] Avoiding platform test coverage regressions

Hi,


I'm writing this email because of a recurring problem with our test coverage in combination with releases of Qt.


Many times in the past we've had the situation where a change was applied to the CI system that temporarily removed an entire platform, for example in favor of adding a new one in steps. I'll cite two examples right off the top of my head, but upon request I can dig up more:


    (1) During times of qtqa-testconfig we added and removed configurations without observing what their test coverage was, and at some point near the 5.3/5.4 release ended up in a situation where our entire cross-platform network stack was only tested partially on Linux, partly as a consequence of removing an older Windows (where we ran tests) in favor of a newer Windows (where we "insignifified" all network tests). We made several releases with a network stack that was untested on Windows and macOS.


    (2) Today we are in the situation where we are building Qt and running tests on macOS 10.11 in the 5.6 branch of Qt. However the changes that added 10.11 to the CI configuration to provide build and test coverage were never applied to the 5.7, 5.8 or the dev branch of Qt, leaving us with no tests run on 10.11.


During a related discussion in https://codereview.qt-project.org/#/c/183219/ I suggested that we use a release blocking bug to track the progress of changing platforms and that way ensure that we don't release Qt before the regression of temporarily removing build and/or test coverage is fixed.


Tony declined the suggestion with the following statement:

"We had that. We had a P0 bug to put 10.11 in to 5.7 as it was already in 5.6, but it got show down as it was seen as definitely not being able to block a release. And this happened again in 5.8. If everything else is fine, a missing platform from CI was seen as not to be able to block the release."


I could not find any mention of that in the release team meeting logs regarding such a decision.


I would like to raise the attention to this topic and request either approval to use blocking release bugs to track these regressions or ask for suggestions of alternate methods to prevent us from repeatedly running into the scenario of releasing Qt with regressed build and test coverage.




Simon