Re: [PATCH] remote-hg: store converted URL

[Junio C Hamano <gitster@pobox.com>]

Junio C Hamano <gitster@pobox.com> writes:

> Max Horn <max@quendi.de> writes:
> ...
>> See also the discussion (yeah, this time a real one ;-) leading to this:
>>   https://github.com/felipec/git/issues/2
>> ...

If I understand correctly, the $backend::$opaqueToken is a contract
between the remote-helper and the remote-$backend that says "When
user wants to interact with the same (foreign) repository, we agreed
to let her use 'origin' nickname.  The remote-helper looks up this
opaque token that corresponds to 'origin' and gives it to the
remote-$backend, and whatever is in the opaque token should be
sufficient for the remote-$backend to figure out how to proceed from
there".

But in this hg::../over/there case, it seems that string is not
sufficient for remote-hg to do so and the contract is broken.

When "git clone $backend::$opaqueToken repo" is run in /dir/ecto/ry,
and then subsequent "git fetch origin" will be run in (a
subdirectory of) /dir/ecto/ry/repo, but anything relative to
/dir/ecto/ry will not work once you go inside /dir/ecto/ry/repo.
The "create a new repository here" argument could even be an
absolute path to a totally different place, so if the
remote-$backend wants to use $opaqueToken as anything relative to
the $(cwd) when "git clone" was invoked, that original location
needs to be available somehow.

Would a new helper protocol message be necessary, so that the
backend can rewrite the $opaqueToken at "clone" time and tell the
helper what to store as URL instead of the original?  I do not think
that is much different from remote-$backend updating the value of the
remote.origin.URL using "git config".

An alternative approach may be for somebody (either the "git clone"
or the remote-$backend) to store a "base directory" when "git clone"
was invoked in remote.origin.dirAtCloneTime variable, so that the
next time remote-$backend runs, it can read that directory and
interpret the $opaqueToken as a relative path to that directory if
it wants to.  That way, nobody needs to rewrite $opaqueToken.

How do other remote helpers solve this, I have to wonder, though.
By not allowing relative paths to a directory?