Add ietf-drums tests, fix parse-address decoding

* test/lisp/mail/ietf-drums-tests.el (ietf-drums-tests):  Test most of
lisp/mail/ietf-drums.el functionality.
* lisp/mail/ietf-drums.el: (ietf-drums-parse-address): Bug fix:
Require rfc2047 when needed (bug#53811).

2 files changed, 164 insertions, 0 deletions

diff --git a/lisp/mail/ietf-drums.el b/lisp/mail/ietf-drums.el
index 952707226f5..9bdc0533e34 100644
--- a/lisp/mail/ietf-drums.el
+++ b/lisp/mail/ietf-drums.el
@@ -191,6 +191,8 @@ the Content-Transfer-Encoding header of a mail."
   "Parse STRING and return a MAILBOX / DISPLAY-NAME pair.
 If DECODE, the DISPLAY-NAME will have RFC2047 decoding performed
 (that's the \"=?utf...q...=?\") stuff."
+  (when decode
+    (require 'rfc2047))
   (with-temp-buffer
     (let (display-name mailbox c display-string)
       (ietf-drums-init string)
diff --git a/test/lisp/mail/ietf-drums-tests.el b/test/lisp/mail/ietf-drums-tests.el
new file mode 100644
index 00000000000..4cc38b8763a
--- /dev/null
+++ b/test/lisp/mail/ietf-drums-tests.el
@@ -0,0 +1,162 @@
+;;; ietf-drums-tests.el --- Test suite for ietf-drums.el  -*- lexical-binding:t -*-
+
+;; Copyright (C) 2022 Free Software Foundation, Inc.
+
+;; Author: Bob Rogers <rogers@rgrjr.com>
+
+;; 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 'ietf-drums)
+
+(ert-deftest ietf-drums-tests ()
+  "Test ietf-drums functionality."
+
+  ;; ietf-drums-remove-comments
+  (should (equal (ietf-drums-remove-comments "random string") "random string"))
+  (should (equal (ietf-drums-remove-comments "random \"non comment\" string")
+                 "random \"non comment\" string"))
+  (should (equal (ietf-drums-remove-comments "random (comment) string")
+                 "random  string"))
+  (should (equal (ietf-drums-remove-comments "random (comment) (string)")
+                 "random  "))
+  (should (equal (ietf-drums-remove-comments
+                  "random (first) (second (and)) (third) not fourth")
+                 "random    not fourth"))
+
+  ;; ietf-drums-remove-whitespace
+  (should (equal (ietf-drums-remove-whitespace "random string")
+                 "randomstring"))
+  (should (equal (ietf-drums-remove-whitespace "random (comment) string")
+                 "random(comment)string"))
+  (should (equal (ietf-drums-remove-whitespace "random \"non comment\" string")
+                 "random\"non comment\"string"))
+  (should (equal (ietf-drums-remove-whitespace "random (comment)\r\n(string)")
+                 "random(comment)(string)"))
+  (should (equal (ietf-drums-remove-whitespace
+                  "random (first) (second (and)) (third) not fourth")
+                 "random(first)(second (and))(third)notfourth"))
+
+  ;; ietf-drums-strip
+  (should (equal (ietf-drums-strip "random string") "randomstring"))
+  (should (equal (ietf-drums-strip "random \"non comment\" string")
+                 "random\"non comment\"string"))
+  (should (equal (ietf-drums-strip "random (comment) string")
+                 "randomstring"))
+  (should (equal (ietf-drums-strip "random (comment) (string)")
+                 "random"))
+  (should (equal (ietf-drums-strip
+                  "random (first) (second (and)) (third) not fourth")
+                 "randomnotfourth"))
+
+  ;; ietf-drums-strip-cte
+  (should (equal (ietf-drums-strip-cte "random \"non comment\" string")
+                 ;; [the " " is still in there because it was quoted
+                 ;; through the "strip".  -- rgr, 5-Feb-22.]
+                 "randomnon commentstring"))
+  (should (equal (ietf-drums-strip-cte "ran(d)do<m@>[s;t:r],,in=g")
+                 "randomstring"))
+
+  ;; ietf-drums-quote-string
+  (should (equal (ietf-drums-quote-string "Bob") "Bob"))
+  (should (equal (ietf-drums-quote-string "Foo Bar") "\"Foo Bar\""))
+
+  ;; ietf-drums-get-comment
+  (should (equal (ietf-drums-get-comment "random string") nil))
+  (should (equal (ietf-drums-get-comment "random (comment) string") "comment"))
+  (should (equal (ietf-drums-get-comment "random \"non comment\" string") nil))
+  (should (equal (ietf-drums-get-comment "\"still (non) comment\" string")
+                 nil))
+  (should (equal (ietf-drums-get-comment "random (comment)\r\nstring")
+                 "comment"))
+  (should (equal (ietf-drums-get-comment "random (comment) (string)") "string"))
+  (should (equal (ietf-drums-get-comment
+                  "random (first) (second (and)) (third) not fourth")
+                 "third"))
+
+  ;; ietf-drums-make-address
+  (should (equal (ietf-drums-make-address "Bob Rogers" "rogers@rgrjr.com")
+                 "\"Bob Rogers\" <rogers@rgrjr.com>"))
+  (should (equal (ietf-drums-make-address nil "rogers@rgrjr.com")
+                 "rogers@rgrjr.com"))
+
+  ;; ietf-drums-parse-address
+  (should (equal (ietf-drums-parse-address "foo@example.com")
+                 '("foo@example.com")))
+  (should (equal (ietf-drums-parse-address "<foo@example.com>")
+                 '("foo@example.com")))
+  (should (equal (ietf-drums-parse-address "'foo' <foo@example.com>")
+                 '("foo@example.com" . "'foo'")))
+  (should (equal (ietf-drums-parse-address "foo <foo@example.com>")
+                 '("foo@example.com" . "foo")))
+  (should (equal (ietf-drums-parse-address "foo <foo@example.com> bar")
+                 ;; [contrary to RFC2822, which wants the display-name
+                 ;; before the address.  -- rgr, 5-Feb-22.]
+                 '("foo@example.com" . "foo bar")))
+  (should (equal (ietf-drums-parse-address " <foo@example.com> foo ")
+                 ;; [ditto.  -- rgr, 5-Feb-22.]
+                 '("foo@example.com" . "foo")))
+  (should (equal (ietf-drums-parse-address "foo@example.com (foo)")
+                 '("foo@example.com" . "foo")))
+  (should (equal (ietf-drums-parse-address "Bar Baz <barbaz@example.com>")
+                 '("barbaz@example.com" . "Bar Baz")))
+  (should (equal (ietf-drums-parse-address "barbaz@example.com (Bar Baz)")
+                 '("barbaz@example.com" . "Bar Baz")))
+  (should (equal (ietf-drums-parse-address
+                  "Bar Baz (ignored) <barbaz@example.com>")
+                 '("barbaz@example.com" . "Bar Baz")))
+  (should (equal (ietf-drums-parse-address "<barbaz@example.com> Bar Baz")
+                 '("barbaz@example.com" . "Bar Baz")))
+  (should (equal (ietf-drums-parse-address
+                  "(Bar Baz not ignored) barbaz@example.com")
+                 ;; [not strictly RFC2822, which expects the name
+                 ;; comment after the address.  -- rgr, 5-Feb-22.]
+                 '("barbaz@example.com" . "Bar Baz not ignored")))
+  (should (equal (ietf-drums-parse-address
+                  "(ignored) <barbaz@example.com> (Bar Baz not ignored)")
+                 '("barbaz@example.com" . "Bar Baz not ignored")))
+  (should (equal (ietf-drums-parse-address
+                  "(ignored) barbaz@example.com (Bar Baz not ignored)")
+                 '("barbaz@example.com" . "Bar Baz not ignored")))
+  ;; Test for RFC2047 token decoding.
+  (should (equal (ietf-drums-parse-address
+                  "=?utf-8?B?0JfQtNGA0LDMgdCy0YHRgtCy0YPQudGC0LUh?= <foo@goo.ru>"
+                  t)
+                 '("foo@goo.ru" . "Здра́вствуйте!")))
+
+  ;; ietf-drums-parse-addresses
+  ;; Note that it's not worth getting too elaborate here, as the heavy
+  ;; lifting is all done by ietf-drums-parse-address.
+  (should (equal (ietf-drums-parse-addresses "foo@example.com")
+                 '(("foo@example.com"))))
+  (should (equal (ietf-drums-parse-addresses
+                  "foo@example.com, bar@example.com")
+                 '(("foo@example.com") ("bar@example.com"))))
+  (should (equal (ietf-drums-parse-addresses
+                  "foo@example.com, quux, bar@example.com")
+                 '(("foo@example.com") ("bar@example.com"))))
+  (should (equal (ietf-drums-parse-addresses
+                  "foo@example.com, Quux Dude <quux@noop.org>, bar@example.com")
+                 '(("foo@example.com") ("quux@noop.org" . "Quux Dude")
+                   ("bar@example.com")))))
+
+(provide 'ietf-drums-tests)
+
+;;; ietf-drums-tests.el ends here