In order to launch a browser on a revision today, the user must use the form:
arc browse Dnnn
A common operation is to want to open the browser to whatever revision is associated with the branch you're working on, without first having to run a separate command (such as arc feature and look for your branch, or git log).
For our users, this is noticeable delta because we used to have:
Which would do exactly this (open the appropriate Review Board review request).
A possible way to support this nicely with arc is to allow use of browse with no further arguments:
Today this merely gives an error message:
Usage Exception: Specify one or more paths or objects to browse. Use the command "arc browse ." if you want to browse this directory.
I understand that arc browse is intended to be multi-purpose. My naive argument for this would be that if you're trying to browse a commit or a directory, you by definition know what you are wanting to browse - whether it's passing . or HEAD or similar.
On the other hand, if you're trying to browse a revision there is a fundamental gap between what you clearly know as a user and what you need to instruct arc to do what you want. As a result, it feels somewhat reasonable to me that the default behavior without arguments is to assume the user wants to browse a revision, and detect the revision of the current branch.
An alternative might be:
arc browse D. # notice the dot ;)
Or some similar syntax that's easy to type and remember, yet also avoids implying to the user that arc browse is only useful for revisions.