1400439 - Issue warning when `mach try` isn't used

Status: RESOLVED WONTFIX

(Developer Services :: Mercurial: hg.mozilla.org, enhancement)

Description

[Gregory Szorc [:gps]]

We're going to require usage of `mach try` some day.

Let's issue a warning on hg.mo when `mach try` isn't being used.

Comment 1

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

Attachment: Bug 1400439 - Issue warning when isn't used

Review commit: https://reviewboard.mozilla.org/r/180958/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/180958/

Comment 2

[Gregory Szorc [:gps]]

Comment on attachment 8909469 [details]
Bug 1400439 - Issue warning when  isn't used

https://reviewboard.mozilla.org/r/180958/#review187588

Things aren't this simple :/

`mach try syntax` doesn't produce a try_task_config.json file.

Instead, what we've done is added common messaging to all `mach try` pushes (see https://hg.mozilla.org/mozilla-central/rev/a2a1b037d342). So, we can implement the detection as searching for "pushed via `mach try`".

But even that isn't sufficient. To avoid false alerts on pushes from old revisions, we'll also want to verify the changeset being pushed has a2a1b037d342 as an ancestor. This can be implemented via something like:

```
MODERN_MACH_TRY_REV = 'a2a1b037d34287da3bfac7a287a55aae779541f3'

if MODERN_MACH_TRY_REV in repo and repo.changelog.isancestor(MODERN_MACH_TRY_REV, ctx.node()):
    ...
```

Comment 3

[Marco Castelluccio [:marco]]

Even if it is not strictly required, basically everyone is using mach try nowadays, so probably not worth finishing this up.