utils: Clean up and add tests.

* haunt/utils.scm (flat-map, string-split-at): Add docstring.
  (file-name-components): Adjust slightly to handle "/".
  (join-file-name-components): Use prefix string join grammar.
  (absolute-file-name): Add docstring.
* test-env.in: New file.
* tests/utils.scm: New file.
* Makefile.am (TESTS, TEST_EXTENSIONS, SCM_LOG_COMPILER,
  AM_SCM_LOG_FLAGS): New variables.
* configure.ac: Add test-env pre-processed file.
* build-aux/test-driver: New file.

tests/utils.scm

@@ -0,0 +1,85 @@
+;;; Haunt --- Static site generator for GNU Guile
+;;; Copyright © 2015 David Thompson <davet@gnu.org>
+;;;
+;;; This file is part of Haunt.
+;;;
+;;; Haunt 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.
+;;;
+;;; Haunt 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 Haunt.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (test-utils)
+  #:use-module (srfi srfi-19)
+  #:use-module (srfi srfi-64)
+  #:use-module (haunt utils))
+
+(test-begin "utils")
+
+(test-equal "flatten, all"
+  '(1 2 3 4 5 6)
+  (flatten '(1 (2 3 (4) (5 (6))))))
+
+(test-equal "flatten, limited depth"
+  '(1 2 3 4 5 (6))
+  (flatten '(1 (2 3 (4) (5 (6)))) 2))
+
+(test-equal "flat-map"
+  '(5 7 9)
+  (flat-map (compose list +) '(1 2 3) '(4 5 6)))
+
+(test-equal "string-split-at, no match"
+  '("foo")
+  (string-split-at "foo" #\z))
+
+(test-equal "string-split-at, match"
+  '("foo" "bar")
+  (string-split-at "foo/bar" #\/))
+
+(test-equal "file-name-components, empty string"
+  '()
+  (file-name-components ""))
+
+(test-equal "file-name-components, root directory"
+  '("")
+  (file-name-components "/"))
+
+(test-equal "file-name-components, full file name"
+  '("share" "haunt")
+  (file-name-components "/share/haunt"))
+
+(test-equal "join-file-name-components"
+  "/share/haunt/info/haunt.info"
+  (join-file-name-components '("share" "haunt" "info" "haunt.info")))
+
+(test-equal "absolute-file-name, already absolute"
+  "/share/haunt"
+  (absolute-file-name "/share/haunt"))
+
+(test-equal "absolute-file-name, relative file name"
+  (string-append (getcwd) "/share/haunt")
+  (absolute-file-name "share/haunt"))
+
+(test-equal "take-up-to, less than n elements"
+  '(1 2 3)
+  (take-up-to 4 '(1 2 3)))
+
+(test-equal "take-up-to, more than n elements"
+  '(1 2)
+  (take-up-to 2 '(1 2 3)))
+
+(test-equal "string->date*"
+  (make-date 0 0 15 06 05 09 2015 (date-zone-offset (current-date)))
+  (string->date* "2015-09-05 06:15"))
+
+(test-end)
+
+
+(exit (zero? (test-runner-fail-count (test-runner-current))))