lint: Fold 'sync-descriptions' script as 'gnu-description' lint checker.

* build-aux/sync-descriptions.scm: Remove.  Move payload to...
* guix/scripts/lint.scm: ... here.
  (escape-quotes, official-gnu-packages*,
  check-gnu-synopsis+description): New procedures.
  (%checkers): Add 'gnu-descriptions'.
* Makefile.am (EXTRA_DIST): Remove build-aux/sync-descriptions.scm.
  (sync-descriptions): Use 'guix lint'.

3 files changed, 61 insertions, 88 deletions

diff --git a/Makefile.am b/Makefile.am
index 075726d309..ee029c3735 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -233,7 +233,6 @@ EXTRA_DIST =						\
   build-aux/check-final-inputs-self-contained.scm	\
   build-aux/download.scm				\
   build-aux/list-packages.scm				\
-  build-aux/sync-descriptions.scm			\
   srfi/srfi-37.scm.in					\
   srfi/srfi-64.scm					\
   srfi/srfi-64.upstream.scm				\
@@ -308,8 +307,7 @@ dist-hook: sync-descriptions gen-ChangeLog assert-no-store-file-names
 distcheck-hook: assert-binaries-available assert-final-inputs-self-contained
 
 sync-descriptions:
-	-$(top_builddir)/pre-inst-env $(GUILE)		\
-	   $(top_srcdir)/build-aux/sync-descriptions.scm
+	-$(top_builddir)/pre-inst-env guix lint --checkers=gnu-description
 
 gen-ChangeLog:
 	if test -d .git; then				\
diff --git a/build-aux/sync-descriptions.scm b/build-aux/sync-descriptions.scm
deleted file mode 100644
index 6ff549c309..0000000000
--- a/build-aux/sync-descriptions.scm
+++ /dev/null
@@ -1,85 +0,0 @@
-;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013 Ludovic Courtès <ludo@gnu.org>
-;;;
-;;; This file is part of GNU Guix.
-;;;
-;;; GNU Guix is free software; you can redistribute it and/or modify it
-;;; under the terms of the GNU General Public License as published by
-;;; the Free Software Foundation; either version 3 of the License, or (at
-;;; your option) any later version.
-;;;
-;;; GNU Guix is distributed in the hope that it will be useful, but
-;;; WITHOUT ANY WARRANTY; without even the implied warranty of
-;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-;;; GNU General Public License for more details.
-;;;
-;;; You should have received a copy of the GNU General Public License
-;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
-
-;;;
-;;; Report package synopses and descriptions that defer from those found in
-;;; the GNU Womb.
-;;;
-
-(use-modules (guix gnu-maintenance)
-             (guix packages)
-             (guix utils)
-             (guix ui)
-             (gnu packages)
-             (srfi srfi-1)
-             (srfi srfi-26)
-             (ice-9 match))
-
-(define official
-  ;; GNU package descriptors from the Womb.
-  (official-gnu-packages))
-
-(define gnus
-  ;; GNU packages available in the distro.
-  (let ((lookup (lambda (p)
-                  (find (lambda (descriptor)
-                          (equal? (gnu-package-name descriptor)
-                                  (package-name p)))
-                        official))))
-    (fold-packages (lambda (package result)
-                     (or (and=> (lookup package)
-                                (cut alist-cons package <> result))
-                         result))
-                   '())))
-
-(define (escape-quotes str)
-  "Replace any quote character in STR by an escaped quote character."
-  (list->string
-   (string-fold-right (lambda (chr result)
-                        (match chr
-                          (#\" (cons* #\\ #\"result))
-                          (_   (cons chr result))))
-                      '()
-                      str)))
-
-;; Iterate over GNU packages.  Report those whose synopsis defers from that
-;; found upstream.
-(for-each (match-lambda
-           ((package . descriptor)
-            (let ((upstream   (gnu-package-doc-summary descriptor))
-                  (downstream (package-synopsis package))
-                  (loc        (or (package-field-location package 'synopsis)
-                                  (package-location package))))
-              (unless (and upstream (string=? upstream downstream))
-                (format (guix-warning-port)
-                        "~a: ~a: proposed synopsis: ~s~%"
-                        (location->string loc) (package-name package)
-                        upstream)))
-
-            (let ((upstream   (gnu-package-doc-description descriptor))
-                  (downstream (package-description package))
-                  (loc        (or (package-field-location package 'description)
-                                  (package-location package))))
-              (when (and upstream
-                         (not (string=? (fill-paragraph upstream 100)
-                                        (fill-paragraph downstream 100))))
-                (format (guix-warning-port)
-                        "~a: ~a: proposed description:~%     \"~a\"~%"
-                        (location->string loc) (package-name package)
-                        (fill-paragraph (escape-quotes upstream) 77 7))))))
-          gnus)
diff --git a/guix/scripts/lint.scm b/guix/scripts/lint.scm
index 237709848f..facc2bf60b 100644
--- a/guix/scripts/lint.scm
+++ b/guix/scripts/lint.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2014 Cyril Roelandt <tipecaml@gmail.com>
 ;;; Copyright © 2014 Eric Bavier <bavier@member.fsf.org>
+;;; Copyright © 2013, 2014 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -219,6 +220,61 @@ line."
                     "file names of patches should start with the package name"
                     'patches))))
 
+(define (escape-quotes str)
+  "Replace any quote character in STR by an escaped quote character."
+  (list->string
+   (string-fold-right (lambda (chr result)
+                        (match chr
+                          (#\" (cons* #\\ #\"result))
+                          (_   (cons chr result))))
+                      '()
+                      str)))
+
+(define official-gnu-packages*
+  (memoize
+   (lambda ()
+     "A memoizing version of 'official-gnu-packages' that returns the empty
+list when something goes wrong, such as a networking issue."
+     (let ((gnus (false-if-exception (official-gnu-packages))))
+       (or gnus '())))))
+
+(define (check-gnu-synopsis+description package)
+  "Make sure that, if PACKAGE is a GNU package, it uses the synopsis and
+descriptions maintained upstream."
+  (match (find (lambda (descriptor)
+                 (string=? (gnu-package-name descriptor)
+                           (package-name package)))
+               (official-gnu-packages*))
+    (#f                                   ;not a GNU package, so nothing to do
+     #t)
+    (descriptor                           ;a genuine GNU package
+     (let ((upstream   (gnu-package-doc-summary descriptor))
+           (downstream (package-synopsis package))
+           (loc        (or (package-field-location package 'synopsis)
+                           (package-location package))))
+       (unless (and upstream (string=? upstream downstream))
+         (format (guix-warning-port)
+                 "~a: ~a: proposed synopsis: ~s~%"
+                 (location->string loc) (package-full-name package)
+                 upstream)))
+
+     (let ((upstream   (gnu-package-doc-description descriptor))
+           (downstream (package-description package))
+           (loc        (or (package-field-location package 'description)
+                           (package-location package))))
+       (when (and upstream
+                  (not (string=? (fill-paragraph upstream 100)
+                                 (fill-paragraph downstream 100))))
+         (format (guix-warning-port)
+                 "~a: ~a: proposed description:~%     \"~a\"~%"
+                 (location->string loc) (package-full-name package)
+                 (fill-paragraph (escape-quotes upstream) 77 7)))))))
+
+
+;;;
+;;; List of checkers.
+;;;
+
 (define %checkers
   (list
    (lint-checker
@@ -226,6 +282,10 @@ line."
      (description "Validate package descriptions")
      (check       check-description-style))
    (lint-checker
+     (name        "gnu-description")
+     (description "Validate synopsis & description of GNU packages")
+     (check       check-gnu-synopsis+description))
+   (lint-checker
      (name        "inputs-should-be-native")
      (description "Identify inputs that should be native inputs")
      (check       check-inputs-should-be-native))