I don’t use this because we just use the standard forge stuff. But yes, there shouldn’t be a reason to “break the build” and for small teams you shouldn’t need advanced tech to solve the issue (like for a bigger team with a large test suite it is tricky).[1]
But it would also be nice with some nice, readable history at the top level. Doesn’t have to be “curated” but you could have highlighted quotes and whatnot... I don’t know. Look at the Git project; the merge commits are decent.[2] The Rust project’s merge commits look like some dogfood factory ground floor where the coolers have malfunctioned. Bunch of weird command-like `r? @ghost rollup=...` which look like they were vacuumed up from GitHub via contributors or maybe also Tina Fey-bot. Then the commit message will the ill-suited MarkDown dump from the PR, including paragraphs with no hard-wrapping,[3] inline links (you can use reference style but okay), or how about some crazy ascii tables that look like a MySQL console[4] when you query a table with 20 columns (exaggeration). But I guess this is the not-rocket-science aesthetic of real serious business going on here.[5]
[1]: Shouldn’t need to buy some company software like whoever is selling this via their history lesson
[2]: A typical one would be “the frobinator in the config parsing segfaulted ..., which has been corrected”. Then with an inline subject-only “log” of all the commits. Pretty old-school.
[3]: The stuff they put in the commit message even uses an arrow to indicate “oh this was too long for me”: `feels like a regression as →` https://github.com/rust-lang/rust/pull/146121
[4]: 1ed3cd7030718935a5c5e5c8f6581f36d8be179f
[5]: Closer to the Linux Kernel style than the Git project, certainly
My opinion is that this situation of a merge skew happens rarely enough not to be a major problem. And personally, I think instead of the merge queues described in the article, it would be overall more beneficial to invest in tooling to automatically revert broken commits in your main branch. Merging the PR into a temporary branch and running tests is a good thing, but it is overly strict to require your main branch to be fast forwarded. You can generally set a time limit of one day or so: as long as tests pass when merging the PR onto a main branch less than one day old, you can just merge it.
But merge queues (talking in general, IDK about the mergify.com product specifically) don't require fast-forwarding as far as the developer is aware. In the simplest case it looks like merging (non-fast-forward) to a temporary branch, then only updating the main branch after tests pass. This is very similar to your auto-revert except the main branch is never broken, so no wasted developer time and confusion when they pull a bad commit to start their PR.
IMHO it is a real shame that all CI doesn't work like this. It should be the default. Just this basic delay and auto-revert is already a nice boost to developer productivity. Not to mention that blocking a merge in the original PR is much less confusing than reverting and requiring a fresh PR to make the change. It adds basically no complexity other than the fact that our tools aren't set up to work this way by default which ends up requiring extra tools which are not as well integrated.
On top of this you can add batching which can be incredibly useful when your CI is slow (including things like deploying to a staging environment and letting it soak for a few hours) which isn't feasible to do per-PR even for fairly small teams.
> February 2 2014, 22:25 […] Thirteen years ago I worked at Cygnus/RedHat […] Ben, Frank, and possibly a few other folks on the team cooked up a system [with a] simple job: automatically maintain a repository of code that always passes all the tests.
I think there’s a big difference between Chromium’s approach and the “not rocket science” rule. AIUI Chromium’s model there are still postsubmits that must pass or a change will be reverted by a group monitoring the queue. This is a big difference in practice vs having a rotation or team that reorders the merge queue and rolls changes up to merge together. In the commit queue model you land faster at the expense of more likely reverts than in the merge queue model.