Use lexical-binding in lpr.el and add rudimentary tests

* lisp/lpr.el: Use lexical-binding.  Remove redundant :group args.
(print-region-function): Declare MS-Windows specific function.
* test/lisp/lpr-tests.el: New file.

1 files changed, 41 insertions, 0 deletions

diff --git a/test/lisp/lpr-tests.el b/test/lisp/lpr-tests.el
new file mode 100644
index 00000000000..bc31982a11d
--- /dev/null
+++ b/test/lisp/lpr-tests.el
@@ -0,0 +1,41 @@
+;;; lpr-tests.el --- Tests for lpr.el  -*- lexical-binding: t -*-
+
+;; Copyright (C) 2021 Free Software Foundation, Inc.
+
+;; 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 <https://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;;; Code:
+
+(require 'ert)
+(require 'lpr)
+
+(ert-deftest lpr-test-printify-region ()
+  (with-temp-buffer
+    (insert "foo\^@-\^h\^k\^n-\^_\177bar")
+    (printify-region (point-min) (point-max))
+    (should (equal (buffer-string) "foo\\^@-\\^H\\^K\\^N-\\^_\\7fbar"))))
+
+(ert-deftest lpr-test-lpr-eval-switch ()
+  (should (equal (lpr-eval-switch "foo") "foo"))
+  (should (equal (lpr-eval-switch (lambda () "foo")) "foo"))
+  (let ((v "foo"))
+    (should (equal (lpr-eval-switch v) "foo")))
+  (should (equal (lpr-eval-switch (list #'identity "foo")) "foo"))
+  (should (equal (lpr-eval-switch 1) nil)))
+
+;;; lpr-tests.el ends here