Add (guix sets).

* guix/sets.scm, tests/sets.scm: New files.sets
* Makefile.am (MODULES, SCM_TESTS): Add them.

tests/sets.scm

@@ -0,0 +1,52 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2015 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/>.
+
+(define-module (test-sets)
+  #:use-module (guix sets)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:use-module (srfi srfi-64))
+
+
+(test-begin "sets")
+
+(test-assert "set-contains?"
+  (let* ((lst (iota 123))
+         (set (list->set lst)))
+    (and (every (cut set-contains? set <>)
+                lst)
+         (not (set-contains? set -1)))))
+
+(test-assert "set->list"
+  (let* ((lst (iota 123))
+         (set (list->set lst)))
+    (lset= = lst (set->list set))))
+
+(test-assert "set-union"
+  (let* ((a  (list 'a))
+         (b  (list 'b))
+         (s1 (setq a))
+         (s2 (setq b))
+         (s3 (set-union s1 s2)))
+    (and (set-contains? s3 a)
+         (set-contains? s3 b))))
+
+(test-end)
+
+
+(exit (= (test-runner-fail-count (test-runner-current)) 0))