I don’t see how to perform extra tests when building a pull request, but not when building an arbitrary branch.
Suppose that I have a branch, and CircleCI is testing that branch.
The CIRCLE_COMPARE_URL environment is not set on those CircleCI jobs.
(With Travis 2.1 it is necessary to use the iynere/compare-url Orb, but the same principle applies.)
Now, I make a pull request from the branch.
CircleCI doesn’t run again, because the code is the same as was tested previously on the branch.
Therefore, any special handling of branches is not triggered.
Can you suggest how to accomplish my goal, of running code for each pull request?
Thanks in advance for your help!