Refactor rfc2047-fold-region slightly and add a couple of tests

* lisp/mail/rfc2047.el (rfc2047--break-line): Refactor out to
avoid code repetition...
(rfc2047-fold-region): ... from this function.

1 files changed, 46 insertions, 0 deletions

diff --git a/test/lisp/mail/rfc2047-tests.el b/test/lisp/mail/rfc2047-tests.el
new file mode 100644
index 00000000000..8f7b345e71e
--- /dev/null
+++ b/test/lisp/mail/rfc2047-tests.el
@@ -0,0 +1,46 @@
+;;; rfc2047-tests.el --- tests for rfc2047.el -*- lexical-binding: t -*-
+
+;; Copyright (C) 2019 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/>.
+
+;;; Code:
+
+(require 'ert)
+(require 'rfc2047)
+
+(ert-deftest test-rfc2047-fold-short ()
+  (with-temp-buffer
+    (insert "Organization: Lots Of Short Words Here Lots Of Short Words Here Lots Of Short Words Here\n")
+    (goto-char (point-min))
+    (rfc2047-fold-field)
+    (should (equal (buffer-string)
+                   "Organization: Lots Of Short Words Here Lots Of Short Words Here Lots Of
+ Short Words Here
+"))))
+
+(ert-deftest test-rfc2047-fold-encoded ()
+  (with-temp-buffer
+    (insert "Subject: This is =?utf-8?Q?=C3=A1?= long subject that's =?utf-8?Q?v=C3=A9ry?= long and =?utf-8?Q?ver=C3=BD?= encoded yes indeed it =?utf-8?Q?=C3=ADs?=\n")
+    (goto-char (point-min))
+    (rfc2047-fold-field)
+    (should (equal (buffer-string)
+                   "Subject: This is =?utf-8?Q?=C3=A1?= long subject that's
+ =?utf-8?Q?v=C3=A9ry?= long and =?utf-8?Q?ver=C3=BD?= encoded yes indeed it
+ =?utf-8?Q?=C3=ADs?=
+"))))
+
+;;; rfc2047-tests.el ends here