import: Remove Nix importer.

This importer has suffered from bitrot and no longer works with current
Nix and Nixpkgs.  See <https://bugs.gnu.org/32339> and
<https://bugs.gnu.org/36255>.

* guix/import/snix.scm, guix/scripts/import/nix.scm,
tests/snix.scm: Remove.
* Makefile.am (MODULES, SCM_TESTS): Remove them.
* guix/scripts/import.scm (importers): Remove "nix".
* build-aux/test-env.in: Remove NIXPKGS variable.
* configure.ac: Remove '--with-nixpkgs' option.
* doc/guix.texi (Invoking guix import): Remove bit about "guix import
nix".
* etc/completion/fish/guix.fish: Likewise.

2 files changed, 2 insertions, 92 deletions

diff --git a/guix/scripts/import.scm b/guix/scripts/import.scm
index 98554ef79b..bbd9a3b190 100644
--- a/guix/scripts/import.scm
+++ b/guix/scripts/import.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2012, 2013, 2014, 2020 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2012, 2013, 2014, 2020, 2021 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2014 David Thompson <davet@gnu.org>
 ;;; Copyright © 2018 Kyle Meyer <kyle@kyleam.com>
 ;;; Copyright © 2019 Ricardo Wurmus <rekado@elephly.net>
@@ -76,7 +76,7 @@ rather than \\n."
 ;;; Entry point.
 ;;;
 
-(define importers '("gnu" "nix" "pypi" "cpan" "hackage" "stackage" "elpa" "gem"
+(define importers '("gnu" "pypi" "cpan" "hackage" "stackage" "elpa" "gem"
                     "go" "cran" "crate" "texlive" "json" "opam"))
 
 (define (resolve-importer name)
diff --git a/guix/scripts/import/nix.scm b/guix/scripts/import/nix.scm
deleted file mode 100644
index 45ca7e3fcf..0000000000
--- a/guix/scripts/import/nix.scm
+++ /dev/null
@@ -1,90 +0,0 @@
-;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2012, 2013, 2016 Ludovic Courtès <ludo@gnu.org>
-;;; Copyright © 2014 David Thompson <davet@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/>.
-
-(define-module (guix scripts import nix)
-  #:use-module (guix ui)
-  #:use-module (guix utils)
-  #:use-module (guix scripts)
-  #:use-module (guix import snix)
-  #:use-module (guix scripts import)
-  #:use-module (srfi srfi-1)
-  #:use-module (srfi srfi-11)
-  #:use-module (srfi srfi-37)
-  #:use-module (ice-9 match)
-  #:export (guix-import-nix))
-
-
-;;;
-;;; Command-line options.
-;;;
-
-(define %default-options
-  '())
-
-(define (show-help)
-  (display (G_ "Usage: guix import nix NIXPKGS ATTRIBUTE
-Import and convert the Nix expression ATTRIBUTE of NIXPKGS.\n"))
-  (display (G_ "
-  -h, --help             display this help and exit"))
-  (display (G_ "
-  -V, --version          display version information and exit"))
-  (newline)
-  (show-bug-report-information))
-
-(define %options
-  ;; Specification of the command-line options.
-  (cons* (option '(#\h "help") #f #f
-                 (lambda args
-                   (show-help)
-                   (exit 0)))
-         (option '(#\V "version") #f #f
-                 (lambda args
-                   (show-version-and-exit "guix import nix")))
-         %standard-import-options))
-
-
-;;;
-;;; Entry point.
-;;;
-
-(define (guix-import-nix . args)
-  (define (parse-options)
-    ;; Return the alist of option values.
-    (args-fold* args %options
-                (lambda (opt name arg result)
-                  (leave (G_ "~A: unrecognized option~%") name))
-                (lambda (arg result)
-                  (alist-cons 'argument arg result))
-                %default-options))
-
-  (let* ((opts (parse-options))
-         (args (filter-map (match-lambda
-                            (('argument . value)
-                             value)
-                            (_ #f))
-                           (reverse opts))))
-    (match args
-      ((nixpkgs attribute)
-       (let-values (((expr loc)
-                     (nixpkgs->guix-package nixpkgs attribute)))
-         (format #t ";; converted from ~a:~a~%~%"
-                 (location-file loc) (location-line loc))
-         expr))
-      (x
-       (leave (G_ "wrong number of arguments~%"))))))