Don't use the PR body in the homu merge message

[emilio]

This is not optimal, but worth discussing it.

Probably we could be smarter and use a regexp to keep just the Fixes|Closes|Adresses #xxx messages.

Fixes servo/servo#11153
Fixes #36

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This change is

[emilio]

Since stripping the reviewable thing is easy, we could also do a servo-specific thing and look for the Thanks for contributing to Servo message, and strip from there.

But that would assume the proper PR description is before that.

[cgwalters]

Do we need to keep Closes: from the original commit? Won't adding a commit with it to master still close the issue?

This patch seems OK to me, but all my uses of Homu are linear = True.

[emilio]

Yes, if it's in the commit description it will still close the issue, but some contributors add the Closes: xxx only to the PR description, and I'm not totally sure if Github would close the issue in that case (probably not).

[Manishearth]

For Rust I find this info super useful since I don't have to leave my terminal and can go through merge commits very fast. I've had to do this less in Servo (changes are more localized and easier to spot), but it's still useful.

IMO stripping reviewable info might be better. Or make it configurable.

[Manishearth]

Also, yeah, github doesn't close the issue otherwise

[nox]

The greetings at the very least should be removed from the commit message, IMO.

[edunham]

@emilio, thanks for starting the discussion on this! It looks to me like the discussion here continued into #40 and reached a resolution that we should use custom tags within the PR template to tell Homu what content to leave out of the merge commit. It looks to me like this should be closed in favor of fixups on #40, but if I missed something in drawing that conclusion, you're more than welcome to reopen.

[emilio]

Nope, thanks for closing this @edunham! :)