Re-merge Pull Request without adding commit to PR branch?

We have builds on Travis running for our Pull Requests:

Travis CI builds a pull request when it is first opened, and whenever commits are added to the pull request. Rather than build the commits that have been pushed to the branch the pull request is from, we build the merge between the source branch and the upstream branch.
Building Pull Requests - Travis CI

Is there a way to create a new merge between the PR branch (e.g. a branch in a fork) and the PR target (mostly master) without adding a new commit to the PR branch?


Background:

We have a lot of PRs with broken test configuration because a) the test configuration was broken when the fork was created and b) tests broke because of external changes to our test environment.

So now we have to trigger a new merge on Travis between the PR branch and the PR target so the fixed test configuration is used and tests can succeed.

Until now we asked our contributors to merge or rebase their branch onto master, which of course is not really necessary in this case. Adding any commit to the PR branch triggers a new branch of the PR branch into the PR target branch, uses the new configuration and (most probably) succeeds.

Having not to add a commit to the PR branch would make this even simpler.

I tried the “Restart build” button, but this did not work - it just restarted all the individual “jobs” of our build but on the same code base as when the build was first triggered.

Closing and re-opening the PR seems to do the job - it starts a new build with a new merge.

Unfortunately this is not a perfect solution, as it also triggers GitHub Project automation:


If the tests are still failing, it has to be moved to that column again.

I would prefer a solution without closing and re-opening a PR.

Also: Don’t close PRs that come from a deleted repo (“unknown repository”), you won’t be able to reopen those at all :confused: