Support <pkg>.opam files

[ghost]

This PR adds support for projects defining multiple opam packages in the same repository.

The behavior is only changed when there is no opam file but some <pkg>.opam files are present. This way opam-publish works the same as before for existing users.

In the case where there is no opam file but there are <pkg>.opam files, opam-publish prepare prepares a submission for each <pkg>.opam. Moreover, if an explicit package name is specified on the command line, it only prepares a submission for <pkg>.opam. It is an error if an explicit name is specified but there is no corresponding <pkg>.opam file.

I tested the patch to create this PR: ocaml/opam-repository#8776

[AltGr]

Oh, that's awesome, thanks! I'll also have use for this :)

Did you make sure to still support the case of directories (pkg1.opam/opam, pkg2.opam/opam...) instead of just files ?

[ghost]

Ah, I didn't know you could do this. I saw the thing about the opam subdirectory, and though you were supposed to look for the <pkg>.opam files in there... I just checked the manual and saw this was documented. I'll update the patch.

BTW for new projects, is there any point in using a directory rather than a file? I imagine that the directory is so that you can group the various files (opam, descr, ...) for a given package. However it seems that opam 2 allows you to put everything in the <pkg>.opam directly.

[AltGr]

Indeed, but it could still have a use for the files/ overlays.

[ghost]

I added support for <pkg>.opam directories.

Note that the patch looks big, but it is actually much smaller if you read it with a good diff tool: https://github.com/janestreet/patdiff/blob/master/bin/patdiff-git-wrapper

[rgrinberg]

@AltGr what's the status on this? I will find this functionality to be very useful very soon.

[AltGr]

I backported to the new 1.3 branch, since the master branch uses the new opam libs and should'nt be used on the current, 1.2 repo (1.2 and 1.3 have no changes in format).

[AltGr]

(which explains the spurious warnings on ocaml/opam-repository#8776)

[AltGr]

This seems to work well for opam-publish prepare, but what about opam-publish submit ?
I have an attempt to add it, need to clean it up and will add that too.

[dbuenzli]

@AltGr I think that a first step for useful for topkg opam submit would be to make the [dir] argument of submit repeatable. More ambitious would be #38 and #29. (And since you are there maybe you could have a look at #43).

[ghost]

So far i've done the submits one by one, but submitting multiple packages at once would be great indeed

[XVilka]

Have you decided what to do with this one?

[AltGr]

This PR was for opam-publish 1.0, it's well obsolete; this is all well supported by opam-publish 2.0 :)