Sync pre-release CPython 3.15 branch from GitHub (2026-06-07)

Summary:
Imported python/cpython `3.15.0b2+dev` from upstream rev [`a642d1a`](https://www.github.com/python/cpython/commit/a642d1ab38cb3199c16898875e86cd13a99b687a) (committed 2026-06-07 13:27:26+00:00).

# Commit Info

- Base: (`3.15.0b2+dev`) - [`934ae3e`](https://www.github.com/python/cpython/commit/934ae3ed153bc01ac44d43c5ad0fc3e01027f98f) (commit date: 2026-06-06 02:46:55+00:00)
- Imported: (`3.15.0b2+dev`) - [`a642d1a`](https://www.github.com/python/cpython/commit/a642d1ab38cb3199c16898875e86cd13a99b687a) (commit date: 2026-06-07 13:27:26+00:00)

# Noteworthy file changes

- Low-signal files (5 added) (NEWS.d, docs, .github)

Complete list of added/removed files: https://www.internalfb.com/intern/everpaste/?color=0&handle=GFcsVCmNtdvoePYFACDOUv0SJ08sbr0LAAAz

Differential Revision: D107809662

fbshipit-source-id: d7f7966363b280b415d6f37008df326281c75b0f

Author: generatedunixname1734921407115435

Doc/c-api/long.rst

@@ -71,6 +71,12 @@ distinguished from a number.  Use :c:func:`PyErr_Occurred` to disambiguate.
    on failure.
 
 
+.. c:function:: PyObject* PyLong_FromUnsignedLongLong(unsigned long long v)
+
+   Return a new :c:type:`PyLongObject` object from a C :c:expr:`unsigned long long`,
+   or ``NULL`` on failure.
+
+
 .. c:function:: PyObject* PyLong_FromInt32(int32_t value)
                 PyObject* PyLong_FromInt64(int64_t value)
 
@@ -81,12 +87,6 @@ distinguished from a number.  Use :c:func:`PyErr_Occurred` to disambiguate.
    .. versionadded:: 3.14
 
 
-.. c:function:: PyObject* PyLong_FromUnsignedLongLong(unsigned long long v)
-
-   Return a new :c:type:`PyLongObject` object from a C :c:expr:`unsigned long long`,
-   or ``NULL`` on failure.
-
-
 .. c:function:: PyObject* PyLong_FromUInt32(uint32_t value)
                 PyObject* PyLong_FromUInt64(uint64_t value)
 

Doc/library/importlib.resources.rst

@@ -240,7 +240,6 @@ For all the following functions:
 
     .. versionchanged:: 3.13
         Multiple *path_names* are accepted.
-        *encoding* and *errors* must be given as keyword arguments.
 
 
 .. function:: is_resource(anchor, *path_names)

Lib/idlelib/iomenu.py

@@ -61,6 +61,7 @@ def set_filename_change_hook(self, hook):
         self.filename_change_hook = hook
 
     filename = None
+    file_timestamp = None
     dirname = None
 
     def set_filename(self, filename):
@@ -127,6 +128,7 @@ def loadfile(self, filename):
                     chars = f.read()
                     fileencoding = f.encoding
                     eol_convention = f.newlines
+                    file_timestamp = self.getmtime(filename)
                     converted = False
             except (UnicodeDecodeError, SyntaxError):
                 # Wait for the editor window to appear
@@ -142,6 +144,7 @@ def loadfile(self, filename):
                     chars = f.read()
                     fileencoding = f.encoding
                     eol_convention = f.newlines
+                    file_timestamp = self.getmtime(filename)
                     converted = True
         except OSError as err:
             messagebox.showerror("I/O Error", str(err), parent=self.text)
@@ -170,6 +173,7 @@ def loadfile(self, filename):
         self.text.insert("1.0", chars)
         self.reset_undo()
         self.set_filename(filename)
+        self.file_timestamp = file_timestamp
         if converted:
             # We need to save the conversion results first
             # before being able to execute the code
@@ -206,7 +210,26 @@ def save(self, event):
         if not self.filename:
             self.save_as(event)
         else:
+            # Check the time of most recent content modification so the
+            # user doesn't accidentally overwrite a newer version of the file.
+            try:
+                file_timestamp = self.getmtime(self.filename)
+            except OSError:
+                pass
+            else:
+                if self.file_timestamp != file_timestamp:
+                    confirm = messagebox.askokcancel(
+                        title="File has changed",
+                        message=(
+                            "The file has changed on disk since reading it!\n\n"
+                            "Do you really want to overwrite it?"),
+                        default=messagebox.CANCEL,
+                        parent=self.text)
+                    if not confirm:
+                        return "break"
+
             if self.writefile(self.filename):
+                self.file_timestamp = self.getmtime(self.filename)
                 self.set_saved(True)
                 try:
                     self.editwin.store_file_breaks()
@@ -219,6 +242,7 @@ def save_as(self, event):
         filename = self.asksavefile()
         if filename:
             if self.writefile(filename):
+                self.file_timestamp = self.getmtime(filename)
                 self.set_filename(filename)
                 self.set_saved(1)
                 try:
@@ -251,6 +275,9 @@ def writefile(self, filename):
                                    parent=self.text)
             return False
 
+    def getmtime(self, filename):
+        return os.stat(filename).st_mtime
+
     def fixnewlines(self):
         """Return text with os eols.