[wish] opam install/pin from opam file

[ygrek]

Currently opam pin allows to install package from location where source is present and opam file is either in the source or in opam repository. It would be nice to be able to install a package just by pointing at opam file location only (i.e. opam file that is separate from the source but that contains an url field which points to the source).

One usecase - testing opam package before submitting PR to opam-repository - currently one has to commit this package to local repository, update that repository, then only do install, rinse and repeat for any error - it is doable but it takes time. It would be nice to just do opam install path_to_opam_file.

[rjbou]

We could add an option for that specific behavior, somethnig like --from-file, that pins the packages with the url in the opam file.
In the meantime, you can speed up your testing process by using pin editing opam pin --edit <pkg> <opam-file-url> and when editing, you paste the repo opam file to test (you can even tweak the OPAMEDITOR env variable to drop the copy paste step, by using a cat command for ex.).

[ygrek]

thanks for the tip