gh-94196: Remove gzip.GzipFile.filename attribute

Doc/library/gzip.rst

@@ -165,6 +165,10 @@ The module defines the following items:
    .. versionchanged:: 3.6
       Accepts a :term:`path-like object`.
 
+   .. versionchanged:: 3.12
+      Remove the ``filename`` attribute, use the :attr:`~GzipFile.name`
+      attribute instead.
+
    .. deprecated:: 3.9
       Opening :class:`GzipFile` for writing without specifying the *mode*
       argument is deprecated.

Doc/whatsnew/3.12.rst

@@ -218,6 +218,12 @@ Removed
   use :func:`os.urandom` or :func:`ssl.RAND_bytes` instead.
   (Contributed by Victor Stinner in :gh:`94199`.)
 
+* :mod:`gzip`: Remove the ``filename`` attribute of :class:`gzip.GzipFile`,
+  deprecated since Python 2.6, use the :attr:`~gzip.GzipFile.name` attribute
+  instead. In write mode, the ``filename`` attribute added ``'.gz'`` file
+  extension if it was not present.
+  (Contributed by Victor Stinner in :gh:`94196`.)
+
 
 Porting to Python 3.12
 ======================

Lib/gzip.py

@@ -212,14 +212,6 @@ def __init__(self, filename=None, mode=None,
         if self.mode == WRITE:
             self._write_gzip_header(compresslevel)
 
-    @property
-    def filename(self):
-        import warnings
-        warnings.warn("use the name attribute", DeprecationWarning, 2)
-        if self.mode == WRITE and self.name[-3:] != ".gz":
-            return self.name + ".gz"
-        return self.name
-
     @property
     def mtime(self):
         """Last modification time read from stream, or None"""

Misc/NEWS.d/next/Library/2022-06-24-09-41-41.gh-issue-94196.r2KyfS.rst

@@ -0,0 +1,4 @@
+:mod:`gzip`: Remove the ``filename`` attribute of :class:`gzip.GzipFile`,
+deprecated since Python 2.6, use the :attr:`~gzip.GzipFile.name` attribute
+instead. In write mode, the ``filename`` attribute added ``'.gz'`` file
+extension if it was not present. Patch by Victor Stinner.