Allow geom_sf() to accept line parameter arrow?

[JakeRuss]

I see the discussion in #2826, that led to PR #2847, but arrow was not included in those additions. Was this intentional or just an oversight?

I think it would be a simple PR and I'll gladly submit it, unless there is a reason it was omitted?

[thomasp85]

This was possibly an oversight - I can't remember if arrows specifically presented any difficulties.

If you are up for creating a PR I'll be happy to review it

[JakeRuss]

I'll see what I can do. What's your timeline for this round of ggplot2 updates?