diff --git a/test/automated/data/decompress/foo-gzipped b/test/automated/data/decompress/foo-gzipped
new file mode 100644
index 00000000000..a68653fcbb9
Binary files /dev/null and b/test/automated/data/decompress/foo-gzipped differ
diff --git a/test/automated/zlib-tests.el b/test/automated/zlib-tests.el
new file mode 100644
index 00000000000..d03d4c981b8
--- /dev/null
+++ b/test/automated/zlib-tests.el
@@ -0,0 +1,40 @@
+;;; zlib-tests.el --- Test suite for zlib.
+
+;; Copyright (C) 2013 Free Software Foundation, Inc.
+
+;; Author: Lars Ingebrigtsen <larsi@gnus.org>
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs 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 Emacs 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 Emacs.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Code:
+
+(require 'ert)
+
+(ert-deftest zlib--decompress ()
+  "Test decompressing a gzipped file."
+  (when (and (fboundp 'zlib-available-p)
+	     (zlib-available-p))
+    (should (string=
+	     (with-temp-buffer
+	       (set-buffer-multibyte nil)
+	       (insert-file-contents-literally "data/decompress/foo-gzipped")
+	       (zlib-decompress-region (point-min) (point-max))
+	       (buffer-string))
+	     "foo\n"))))
+
+(provide 'zlib-tests)
+
+;;; zlib-tests.el ends here.