From 1.9.x, body: "empty_body" is not working

[tanvn]

Today, I tried to update from 1.5.0 to 1.9.1 and found out that the setting body : "empty_body" is not working anymore.
Below is my yaml bulldozer setting file.

version: 1

merge:
  whitelist:
    labels: ["merge-me"]
  blacklist:
    labels: ["do-not-merge","wip"]
  method: squash
  options:
    squash:
      title: "pull_request_title"
      body: "empty_body"
  delete_after_merge: true

update:
  blacklist:
    labels: ["do-not-update", "wip"]
  whitelist:
    labels: ["update-me"]

I have tried 1.5.0 to 1.8.0 and it worked well.
From 1.9.0 when merged, the message body contains all commit messages and it ignored the body : "empty_body" setting.

[bluekeyes]

Thanks for reporting this with the specific version that is broken. It looks like this is due to a change in behavior in the latest go-github library, introduced in google/go-github#1447. I guess we'll have to change Bulldozer to use a string with a single space for the empty_body case to avoid the empty value detection. I believe GitHub trims whitespace from the message, so the end result should be the same.

On the other hand, this means we can probably remove the code in Bulldozer for summarizing commits and instead use the native GitHub functionality, now that it is exposed via go-github.