gh-152638: Deprecate tkinter.filedialog.askopenfiles()

Doc/deprecations/pending-removal-in-3.18.rst

@@ -11,6 +11,14 @@ Pending removal in Python 3.18
     C implementation, has been deprecated since Python 3.13.
     (Contributed by Serhiy Storchaka in :gh:`89902`.)
 
+* :mod:`tkinter`:
+
+  * :func:`tkinter.filedialog.askopenfiles` has been deprecated since Python
+    3.16.  Iterate over the names returned by
+    :func:`~tkinter.filedialog.askopenfilenames` and open them one by one
+    instead.
+    (Contributed by Serhiy Storchaka in :gh:`152638`.)
+
 * Deprecations defined by :pep:`829`:
 
   * ``import`` lines in :file:`{name}.pth` files are silently ignored.

Doc/library/dialog.rst

@@ -165,15 +165,23 @@ versions, so test the result for truth rather than comparing it with a
 specific value.
 
 .. function:: askopenfile(mode="r", **options)
-              askopenfiles(mode="r", **options)
 
-   Create an :class:`Open` dialog.
-   :func:`askopenfile` returns the opened file object, or ``None`` if the
-   dialog is cancelled.
-   :func:`askopenfiles` returns a list of the opened file objects, or an empty
-   tuple if cancelled.
+   Create an :class:`Open` dialog and return the opened file object, or
+   ``None`` if the dialog is cancelled.
+   The file is opened in mode *mode* (read-only ``'r'`` by default).
+
+.. function:: askopenfiles(mode="r", **options)
+
+   Create an :class:`Open` dialog and return a list of the opened file
+   objects, or an empty tuple if cancelled.
    The files are opened in mode *mode* (read-only ``'r'`` by default).
 
+   .. deprecated-removed:: next 3.18
+      Opening several files at once is error-prone, and the returned list
+      cannot be used in a :keyword:`with` statement.
+      Iterate over the names returned by :func:`askopenfilenames` and open
+      them one by one instead.
+
 .. function:: asksaveasfile(mode="w", **options)
 
    Create a :class:`SaveAs` dialog and return the opened file object, or

Doc/whatsnew/3.16.rst

@@ -550,6 +550,15 @@ New deprecations
     3.9, now issues a deprecation warning on use. This property is slated for
     removal in 3.21. Use ``ast.Tuple.elts`` instead.
 
+* :mod:`tkinter`:
+
+  * :func:`tkinter.filedialog.askopenfiles` is deprecated and slated for
+    removal in Python 3.18.  Opening several files at once is error-prone, and
+    the returned list cannot be used in a :keyword:`with` statement.  Iterate
+    over the names returned by :func:`~tkinter.filedialog.askopenfilenames` and
+    open them one by one instead.
+    (Contributed by Serhiy Storchaka in :gh:`152638`.)
+
 .. Add deprecations above alphabetically, not here at the end.
 
 .. include:: ../deprecations/pending-removal-in-3.17.rst

Lib/test/test_tkinter/test_filedialog.py

@@ -69,5 +69,13 @@ def test_subclasses(self):
                 self.assertEqual(d.top.title(), cls.title)
 
 
+class DeprecationTest(unittest.TestCase):
+
+    def test_askopenfiles_deprecated(self):
+        with swap_attr(filedialog, 'askopenfilenames', lambda **kw: ()):
+            with self.assertWarns(DeprecationWarning):
+                filedialog.askopenfiles()
+
+
 if __name__ == "__main__":
     unittest.main()

Lib/tkinter/filedialog.py

@@ -18,6 +18,7 @@
 
 import fnmatch
 import os
+import warnings
 from tkinter import (
     Frame, LEFT, YES, BOTTOM, Entry, TOP, Button, Tk, X,
     Toplevel, RIGHT, Y, END, Listbox, BOTH, Scrollbar,
@@ -418,6 +419,11 @@ def askopenfiles(mode = "r", **options):
     returns a list of open file objects or an empty list if
     cancel selected
     """
+    warnings._deprecated(
+        "tkinter.filedialog.askopenfiles",
+        message=f"{warnings._DEPRECATED_MSG}; iterate over the names returned "
+                "by askopenfilenames() and open them instead",
+        remove=(3, 18))
 
     files = askopenfilenames(**options)
     if files:

Misc/NEWS.d/next/Library/2026-06-29-21-59-08.gh-issue-152638.92dpzo.rst

@@ -0,0 +1,4 @@
+Deprecate :func:`tkinter.filedialog.askopenfiles`.  Opening several files at
+once is error-prone and the returned list cannot be used in a :keyword:`with`
+statement; iterate over the names returned by
+:func:`tkinter.filedialog.askopenfilenames` and open them one by one instead.