Add initial tests for wdired.el

* test/lisp/wdired-tests.el: New file.

test/lisp/wdired-tests.el

+;;; wdired-tests.el --- tests for wdired.el          -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2018 Free Software Foundation, Inc.
+
+;; This file is part of GNU Emacs.
+
+;; This program 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.
+
+;; This program 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 this program.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Code:
+
+(require 'ert)
+(require 'dired)
+
+(ert-deftest wdired-test-bug32173-01 ()
+  "Test using non-nil wdired-use-interactive-rename.
+Partially modifying a file name should succeed."
+  (let* ((test-dir (make-temp-file "test-dir-" t))
+	 (test-file (concat (file-name-as-directory test-dir) "foo.c"))
+	 (replace "bar")
+	 (new-file (replace-regexp-in-string "foo" replace test-file))
+	 (wdired-use-interactive-rename t))
+    (write-region "" nil test-file nil 'silent)
+    (advice-add 'dired-query ; Don't ask confirmation to overwrite a file.
+                :override
+                (lambda (_sym _prompt &rest _args) (setq dired-query t))
+                '((name . "advice-dired-query")))
+    (let ((buf (find-file-noselect test-dir)))
+      (unwind-protect
+	  (with-current-buffer buf
+	    (should (equal (dired-file-name-at-point) test-file))
+	    (dired-toggle-read-only)
+	    (kill-region (point) (progn (search-forward ".")
+					(forward-char -1) (point)))
+	    (insert replace)
+	    (wdired-finish-edit)
+	    (should (equal (dired-file-name-at-point) new-file)))
+	(if buf (kill-buffer buf))
+	(delete-directory test-dir t)))))
+
+(ert-deftest wdired-test-bug32173-02 ()
+  "Test using non-nil wdired-use-interactive-rename.
+Aborting an edit should leaving original file name unchanged."
+  (let* ((test-dir (make-temp-file "test-dir-" t))
+	 (test-file (concat (file-name-as-directory test-dir) "foo.c"))
+	 (wdired-use-interactive-rename t))
+    (write-region "" nil test-file nil 'silent)
+    ;; Make dired-do-create-files-regexp a noop to mimic typing C-g
+    ;; at its prompt before wdired-finish-edit returns.
+    (advice-add 'dired-do-create-files-regexp
+                :override
+                (lambda (&rest _) (ignore))
+                '((name . "advice-dired-do-create-files-regexp")))
+    (let ((buf (find-file-noselect test-dir)))
+      (unwind-protect
+	  (with-current-buffer buf
+	    (should (equal (dired-file-name-at-point) test-file))
+	    (dired-toggle-read-only)
+	    (kill-region (point) (progn (search-forward ".")
+					(forward-char -1) (point)))
+	    (insert "bar")
+	    (wdired-finish-edit)
+	    (should (equal (dired-get-filename) test-file)))
+	(if buf (kill-buffer buf))
+	(delete-directory test-dir t)))))
+
+(ert-deftest wdired-test-unfinished-edit-01 ()
+  "Test editing a file name without saving the change.
+Finding the new name should be possible while still in
+wdired-mode."
+  :expected-result (if (< emacs-major-version 27) :failed :passed)
+  (let* ((test-dir (make-temp-file "test-dir-" t))
+	 (test-file (concat (file-name-as-directory test-dir) "foo.c"))
+	 (replace "bar")
+	 (new-file (replace-regexp-in-string "foo" replace test-file)))
+    (write-region "" nil test-file nil 'silent)
+    (let ((buf (find-file-noselect test-dir)))
+      (unwind-protect
+	  (with-current-buffer buf
+	    (should (equal (dired-file-name-at-point) test-file))
+	    (dired-toggle-read-only)
+	    (kill-region (point) (progn (search-forward ".")
+					(forward-char -1) (point)))
+	    (insert replace)
+	    (should (equal (dired-get-filename) new-file))))
+	(when buf
+	  (with-current-buffer buf
+            ;; Prevent kill-buffer-query-functions from chiming in.
+	    (set-buffer-modified-p nil)
+	    (kill-buffer buf)))
+	(delete-directory test-dir t))))
+
+
+(provide 'wdired-tests)
+;;; wdired-tests.el ends here