New ert-with-display-current-buffer defmacro.scratch/ert-play-keys

* test/lisp/simple-tests.el (undo-test-kill-c-a-then-undo)
 (undo-test-point-after-forward-kill):
* test/lisp/erc/erc-scenarios-spelling.el
 (erc-scenarios-spelling--auto-correct): Use `ert-with-display-current-buffer'
 rather than `pop-to-buffer-same-window'.

* lisp/emacs-lisp/ert.el (ert-with-display-current-buffer): New defmacro.

3 files changed, 69 insertions, 55 deletions

diff --git a/lisp/emacs-lisp/ert.el b/lisp/emacs-lisp/ert.el
index 924201e6445..1478188132c 100644
--- a/lisp/emacs-lisp/ert.el
+++ b/lisp/emacs-lisp/ert.el
@@ -3173,9 +3173,9 @@ See `ert-call-with-buffer-renamed' for details."
 
 KEYS shall have the same format as in a call to function `kmacro'.
 
-A prior call to (pop-to-buffer-same-window (current-buffer)) is
-necessary when the keys KEYS start commands acting on the current
-buffer."
+This macro should be expanded within the body of
+`ert-with-display-current-buffer' when the keys KEYS start commands
+acting on the current buffer."
   `(funcall
     (kmacro ,keys)))
 
@@ -3184,13 +3184,27 @@ buffer."
 
 KEYS-STRING shall be a string.
 
-A prior call to (pop-to-buffer-same-window (current-buffer)) is
-necessary when the keys sequence resulting from KEYS-STRING start
-commands acting on the current buffer."
+This macro should be expanded within the body of
+`ert-with-display-current-buffer' when the keys sequence resulting from
+KEYS-STRING start commands acting on the current buffer."
   (let ((keys (apply #'vector (mapcar #'identity keys-string))))
     `(funcall
       (kmacro ,keys))))
 
+(defmacro ert-with-display-current-buffer (&rest body)
+  "Execute BODY after trying to display current buffer in the same window
+with `pop-to-buffer-same-window'.
+
+This macro restores the old window if changed by
+`pop-to-buffer-same-window' after execution of body. This macro does not
+change the list of currently selected buffer."
+  (let ((old-window (make-symbol "old-window")))
+    `(let ((,old-window (selected-window)))
+       (pop-to-buffer-same-window (current-buffer) t)
+       (unwind-protect
+           (progn ,@body)
+         (select-window ,old-window t)))))
+
 
 ;;; Obsolete
 
diff --git a/test/lisp/erc/erc-scenarios-spelling.el b/test/lisp/erc/erc-scenarios-spelling.el
index 15196e485be..88e64ce7cca 100644
--- a/test/lisp/erc/erc-scenarios-spelling.el
+++ b/test/lisp/erc/erc-scenarios-spelling.el
@@ -67,30 +67,30 @@
         (funcall expect 10 "<alice> tester, welcome!")
 
         ;; Insert a command with one misspelled word.
-        (pop-to-buffer-same-window (current-buffer))
-        (ert-play-keys-in-string "\M->/AMSG an/dor /gmsg one fsbot two frob my shoe")
-        (funcall expect 10 "shoe")
-
-        (let* ((ovs (overlays-in erc-input-marker (point)))
-               (ov1 (pop ovs))
-               (ov2 (pop ovs)))
-          ;; At this point, flyspell should have done its thing.  There
-          ;; should be two overlays: one on "dor" and the other on
-          ;; "frob".  The spelling module's modifications should have
-          ;; prevented the two valid slash commands as well as "fsbot"
-          ;; from being highlighted.
-          (should-not ovs)
-          (should (flyspell-overlay-p ov1))
-          (should (equal "dor" (buffer-substring (overlay-start ov1)
-                                                 (overlay-end ov1))))
-          (should (flyspell-overlay-p ov2))
-          (should (equal "frob" (buffer-substring (overlay-start ov2)
-                                                  (overlay-end ov2))))
-          (goto-char (overlay-start ov2))
-
-          ;; Depending on the machine, this should become something
-          ;; like: "/AMSG an/dor /gmsg one fsbot two Rob my shoe".
-          (ert-play-keys "M-TAB")
+        (ert-with-display-current-buffer
+         (ert-play-keys-in-string "\M->/AMSG an/dor /gmsg one fsbot two frob my shoe")
+         (funcall expect 10 "shoe")
+
+         (let* ((ovs (overlays-in erc-input-marker (point)))
+                (ov1 (pop ovs))
+                (ov2 (pop ovs)))
+           ;; At this point, flyspell should have done its thing.  There
+           ;; should be two overlays: one on "dor" and the other on
+           ;; "frob".  The spelling module's modifications should have
+           ;; prevented the two valid slash commands as well as "fsbot"
+           ;; from being highlighted.
+           (should-not ovs)
+           (should (flyspell-overlay-p ov1))
+           (should (equal "dor" (buffer-substring (overlay-start ov1)
+                                                  (overlay-end ov1))))
+           (should (flyspell-overlay-p ov2))
+           (should (equal "frob" (buffer-substring (overlay-start ov2)
+                                                   (overlay-end ov2))))
+           (goto-char (overlay-start ov2))
+
+           ;; Depending on the machine, this should become something
+           ;; like: "/AMSG an/dor /gmsg one fsbot two Rob my shoe".
+           (ert-play-keys "M-TAB"))
           (should (equal (overlays-in erc-input-marker (point-max))
                          (list ov1)))))
 
diff --git a/test/lisp/simple-tests.el b/test/lisp/simple-tests.el
index a10d881b08b..fe034e1edf9 100644
--- a/test/lisp/simple-tests.el
+++ b/test/lisp/simple-tests.el
@@ -731,35 +731,35 @@ See bug#35036."
 ;; https://lists.gnu.org/r/emacs-devel/2015-11/msg01652.html
 (defun undo-test-kill-c-a-then-undo ()
   (with-temp-buffer
-    (pop-to-buffer-same-window (current-buffer))
-    (setq buffer-undo-list nil)
-    (insert "a\nb\nc\n")
-    (goto-char (point-max))
-    ;; We use a keyboard macro because it adds undo events in the same
-    ;; way as if a user were involved.
-    (ert-play-keys [left
-                    ;; Delete "c"
-                    backspace
-                    left left left
-                    ;; Delete "a"
-                    backspace
-                    ;; C-/ or undo
-                    ?\C-/
-                    ])
+    (ert-with-display-current-buffer
+     (setq buffer-undo-list nil)
+     (insert "a\nb\nc\n")
+     (goto-char (point-max))
+     ;; We use a keyboard macro because it adds undo events in the same
+     ;; way as if a user were involved.
+     (ert-play-keys [left
+                     ;; Delete "c"
+                     backspace
+                     left left left
+                     ;; Delete "a"
+                     backspace
+                     ;; C-/ or undo
+                     ?\C-/
+                     ]))
     (point)))
 
 (defun undo-test-point-after-forward-kill ()
   (with-temp-buffer
-    (pop-to-buffer-same-window (current-buffer))
-    (setq buffer-undo-list nil)
-    (insert "kill word forward")
-    ;; Move to word "word".
-    (goto-char 6)
-    (ert-play-keys [;; kill-word
-                    C-delete
-                    ;; undo
-                    ?\C-/
-                    ])
+    (ert-with-display-current-buffer
+     (setq buffer-undo-list nil)
+     (insert "kill word forward")
+     ;; Move to word "word".
+     (goto-char 6)
+     (ert-play-keys [;; kill-word
+                     C-delete
+                     ;; undo
+                     ?\C-/
+                     ]))
     (point)))
 
 (ert-deftest undo-point-in-wrong-place ()