gh pr create Add option to use first commit as PR title/description

[billyvg]

Describe the feature or problem you’d like to solve

gh pr create --fill has a good default if you only have a single commit: it creates a PR with the commit's details as title/description. However I generally write my first commit's message knowing that it will be used as the PR title/desc and will have follow-up commits that I expect will be squashed at some point. When using gh pr create --fill when there are multiple commits, it uses the branch name as PR title and the list of git commit titles as the PR description.

Proposed solution

Add a CLI option that will always fill the PR title/description using only the first commit's message. This won't disrupt the default and helps support a different and reasonable workflow.

[vilmibm]

Since --fill is used from scripts, this would be a breaking change. marking for discussion in our next sync.

[billyvg]

Since --fill is used from scripts, this would be a breaking change. marking for discussion in our next sync.

What if the option accepted an arg, or if it were a new option, in order to avoid a breaking change?

[mislav]

We discussed this and we're open to gh pr create --fill-first, a new flag. We definitely want to keep backwards compatibility with --fill, which was designed to emulate the web behavior of creating a PR.

People who want to help us implement this can start here:

cli/pkg/cmd/pr/create/create.go

Lines 483 to 484 in 8460a70

	if opts.Autofill || !opts.TitleProvided || !opts.BodyProvided {
	err := initDefaultTitleBody(ctx, state)

[kousikmitra]

If gh pr create --fill-first is finalized I can take this up.

Expectation:

• --fill-first flag to be added
  - --fill and --fill-first both cant be used together
• If --fill-first is used then
  - In case there's only one commit, title should be filled from commit message and body to be filled from commit description (same as current --fill behaviour)
  - In case there are multiple commits, First commit message should be used as title and all commit message should go in PR body

Please let me know if I am missing out anything.

[mislav]

@kousikmitra: that sounds almost correct, just a clarification: if --fill-first is used, there is no difference in behavior when a PR has 1 commit or more than 1 commit. In both cases, the subject of the first commit becomes PR title, and the description of the first commit becomes PR body.

[kousikmitra]

Got it. Will raise a PR soon.

[natebrunette]

It would be nice if you could specific a commit and have it default to HEAD

[kousikmitra]

It would be nice if you could specific a commit and have it default to HEAD

It doesn't default to HEAD but the first commit of the difference HEAD...{default branch}.
We can have an option to specify a commit to use but I personally don't see any reason to have that option.

[natebrunette]

For example, I might do the main work first and then do some other refactoring work that I want to keep separate as additional work afterwards (spacing changes, rearranging lists, etc). I'd like to be able to specify the first commit I did for the --fill. In different cases I might reverse the order.