refresh: Discard PyPI updater when Guile-JSON is missing.

Reported by Sleep_Walker and Mathieu Lirzin <mthl@gnu.org>.

* guix/scripts/refresh.scm (maybe-updater, list-updaters): New macros.
  (%updaters): Use 'list-updaters' instead of 'list'.  Make
  %PYPI-UPDATER conditional.
This commit is contained in:
Ludovic Courtès 2015-11-08 21:57:42 +01:00
parent d8c97beb06
commit b68d2dbf08

View file

@ -30,7 +30,6 @@ (define-module (guix scripts refresh)
#:use-module ((guix gnu-maintenance) #:select (%gnu-updater))
#:use-module (guix import elpa)
#:use-module (guix import cran)
#:use-module (guix import pypi)
#:use-module (guix gnupg)
#:use-module (gnu packages)
#:use-module ((gnu packages commencement) #:select (%final-inputs))
@ -149,12 +148,43 @@ (define (show-help)
;;; Updates.
;;;
(define-syntax maybe-updater
;; Helper macro for 'list-udpaters'.
(lambda (s)
(syntax-case s (=>)
((_ ((module => updater) rest ...) (result ...))
(let ((met? (false-if-exception
(resolve-interface (syntax->datum #'module)))))
(if met?
#'(maybe-updater (rest ...)
(result ... (@ module updater)))
#'(maybe-updater (rest ...) (result ...)))))
((_ (updater rest ...) (result ...))
#'(maybe-updater (rest ...) (result ... updater)))
((_ () result)
#'result))))
(define-syntax-rule (list-updaters updaters ...)
"Expand to '(list UPDATERS ...)' but only the subset of UPDATERS that are
either unconditional, or have their requirement met.
A conditional updater has this form:
((SOME MODULE) => UPDATER)
meaning that UPDATER is added to the list if and only if (SOME MODULE) could
be resolved at macro expansion time.
This is a way to discard at macro expansion time updaters that depend on
unavailable optional dependencies such as Guile-JSON."
(maybe-updater (updaters ...) (list)))
(define %updaters
;; List of "updaters" used by default. They are consulted in this order.
(list %gnu-updater
%elpa-updater
%cran-updater
%pypi-updater))
(list-updaters %gnu-updater
%elpa-updater
%cran-updater
((guix import pypi) => %pypi-updater)))
(define (lookup-updater name)
"Return the updater called NAME."