Re: 'python-build-system'

[ludo@gnu.org (Ludovic Courtès)]

Nikita Karetnikov <nikita@karetnikov.org> skribis:

>> If you append (package-native-search-paths python) to the list of search
>> paths, then PYTHONPATH will automagically be defined appropriately (see
>> <http://lists.gnu.org/archive/html/bug-guix/2013-03/msg00158.html>.)
>
>> If you don’t, then PYTHONPATH will be undefined, unless you explicitly
>> define it in build/python-build-system.scm, which is not the recommended
>> option.
>
>> So just mimic the change made in the above commit for perl-build-system.
>
> OK, I've added it.  Should I remove the following part?
>
> +  (let* ((out  (assoc-ref outputs "out"))
> +         (var `("PYTHONPATH" prefix
> +                (,(string-append out "/lib/python"
> +                                 python-version "/site-packages")))))
> +    (for-each (lambda (dir)
> +                (let ((files (list-of-files dir)))
> +                  (for-each (cut wrap-program <> var)
> +                            files)))
> +              bindirs)))
>
> Or is it a different issue?

Yes, see below.

[...]

> +(define* (python-build store name source inputs
> +                       #:key
> +                       (python (@ (gnu packages python) python))
> +                       (python-version
> +                        (string-take (package-version
> +                                      (@ (gnu packages python) python)) 3))
> +                       (tests? #t)
> +                       (configure-flags ''())
> +                       (phases '(@ (guix build python-build-system)
> +                                   %standard-phases))
> +                       (outputs '("out"))
> +                       (search-paths '())
> +                       (system (%current-system))
> +                       (guile #f)
> +                       (imported-modules '((guix build python-build-system)
> +                                           (guix build gnu-build-system)
> +                                           (guix build utils)))
> +                       (modules '((guix build python-build-system)
> +                                  (guix build gnu-build-system)
> +                                  (guix build utils))))
> +  "Build SOURCE using PYTHON, and with INPUTS.  This assumes that SOURCE
> +provides a 'setup.py' file as its build system."
> +  (define python-search-paths
> +    (append (package-native-search-paths python)
> +            (standard-search-paths)))
> +
> +  (define builder
> +    `(begin
> +       (use-modules ,@modules)
> +       (python-build #:name ,name
> +                     #:source ,(if (and source (derivation-path? source))
> +                                   (derivation-path->output-path source)
> +                                   source)
> +                     #:configure-flags ,configure-flags
> +                     #:system ,system
> +                     #:test-target "test"
> +                     #:tests? ,tests?
> +                     #:outputs %outputs
> +                     #:python-version ,python-version
> +                     #:search-paths ',(map search-path-specification->sexp
> +                                           (append python-search-paths
> +                                                   (standard-search-paths)))

Typo here.  Should be:

  (append python-search-paths search-paths)

Otherwise the ‘search-paths’ argument would not be honored.

[...]

> +(define* (wrap #:key outputs python-version #:allow-other-keys)
> +  (define (list-of-files dir)
> +    (map (cut string-append dir "/" <>)
> +         (or (scandir dir (lambda (f)
> +                            (let ((s (stat (string-append dir "/" f))))
> +                              (eq? 'regular (stat:type s)))))
> +             '())))
> +
> +  (define bindirs
> +    (append-map (match-lambda
> +                 ((_ . dir)
> +                  (list (string-append dir "/bin")
> +                        (string-append dir "/sbin"))))
> +                outputs))
> +
> +  (let* ((out  (assoc-ref outputs "out"))
> +         (var `("PYTHONPATH" prefix
> +                (,(string-append out "/lib/python"
> +                                 python-version "/site-packages")))))

We also need to account for extra Python modules the package depends on:

  (let* (...
         (var `("PYTHONPATH" prefix
                ,(cons (string-append out "/lib/python"
                                      python-version "/site-packages")
                       (search-path-as-string->list
                        (or (getenv "PYTHONPATH") "")))))
    ...)

To answer your previous question, this ‘wrap’ phase serves a different
(but related) purpose than the ‘native-search-paths’ thing: it ensures
that the ‘bzr’ program, when run by the user, finds all its Python
modules.

[...]

> +(define-public bazaar
> +  (package
> +    (name "bazaar")
> +    (version "2.5.1")
> +    (source
> +     (origin
> +      (method url-fetch)
> +      (uri (string-append "https://launchpad.net/bzr/2.5/" version
> +                          "/+download/bzr-" version ".tar.gz"))
> +      (sha256
> +       (base32
> +        "10krjbzia2avn09p0cdlbx2wya0r5v11w5ymvyl72af5dkx4cwwn"))))
> +    (build-system python-build-system)
> +    (inputs
> +     ;; FIXME: 'tools/packaging/lp-upload-release' and 'tools/weavemerge.sh'
> +     ;; require Zsh.

“Note:” rather than “FIXME:”.

> +     `(("gettext" ,guix:gettext)))
> +    (arguments
> +     `(#:tests? #f))

Could you add a comment stating what’s wrong with the test suite?  Or,
if it’s easily doable, just make it pass (if it’s not, it can be done
later.)

With these changes in place, OK to commit.

Thanks!

Ludo’.