* lisp/doc-view.el (doc-view--text-view-mode): Derive from text-mode.

1 files changed, 9 insertions, 3 deletions

diff --git a/lisp/doc-view.el b/lisp/doc-view.el
index 53ae351abd8..a7069072603 100644
--- a/lisp/doc-view.el
+++ b/lisp/doc-view.el
@@ -1480,10 +1480,9 @@ For now these keys are useful:
 ;; can easily distinguish when we want to toggle back because
 ;; text-mode is a likely candidate for a default major-mode
 ;; (bug#34451).
-(defun doc-view--text-view-mode ()
+(define-derived-mode doc-view--text-view-mode text-mode "DV/Text"
   "View mode used in DocView's text buffers."
-  (view-mode)
-  (setq major-mode 'doc-view--text-view-mode))
+  (view-mode))
 
 (defun doc-view-open-text ()
   "Display the current doc's contents as text."
@@ -1496,6 +1495,10 @@ For now these keys are useful:
                 (buffer-undo-list t)
                 (dv-bfn doc-view--buffer-file-name))
             (erase-buffer)
+            ;; FIXME: Replacing the buffer's PDF content with its txt rendering
+            ;; is pretty risky.  We should probably use *another*
+            ;; buffer instead, so there's much less risk of
+            ;; overwriting the PDF file with some text rendering.
             (set-buffer-multibyte t)
             (insert-file-contents txt)
             (doc-view--text-view-mode)
@@ -1504,6 +1507,9 @@ For now these keys are useful:
             (doc-view-minor-mode)
             (add-hook 'write-file-functions
                       (lambda ()
+                        ;; FIXME: If the user changes major mode and then
+                        ;; saves the buffer, the PDF file will be clobbered
+                        ;; with its txt rendering!
                         (when (eq major-mode 'doc-view--text-view-mode)
                           (error "Cannot save text contents of document %s"
                                  buffer-file-name)))