Re: git subtree error (just how do you expect me to merge 0 trees?)

Junio C Hamano [off-list ref] writes:

quoted

With one positional option, git-subtree add simply assumes
it's a refspec.  Is there an easy way to check whether a string is a
proper refspec?  Even better would be a way to check if a string is a
path to a git repository.

Do you literally mean "a path to a repository" in the above, or do
you mean "a remote that is like what is accepted by 'git fetch'"?

It's the latter as git-subtree calls git-fetch to do the work of
getting revisions.

On the other hand, if you mean the command takes a remote and an
optional list of refspecs just like "git fetch" does, then I am not
sure it is a good design in the first place to allow "refspecs
only", if only to keep the interface similar to "git fetch" (you
cannot omit remote and give refspecs, as you cannot interpret
refspecs without knowing in the context of which remote they are to
be interpreted).

If just a refspec is given, git-subtree does a rev-parse in the current
directory and that seems to work fine.  It's what I as a user would
expect to happen.

I would imagine you could disambiguate and default to "origin" or
something when you guessed that remote was omitted if you really
wanted to, with a syntacitical heuristics, such as "a refspec will
never have two colons in it", "a URL tends to begin with a short
alphabet word, a colon and double-slash", etc.

Hmm...I haven't added code to verify the repository/remote argument if
given.  I suppose a rev-parse --verify would suffice?

                        -David