Issue #28227: gzip now supports pathlib

Patch by Ethan Furman.

Lib/test/test_gzip.py

@@ -5,6 +5,7 @@ import unittest
 from test import support
 from test.support import bigmemtest, _4G
 import os
+import pathlib
 import io
 import struct
 import array
@@ -67,6 +68,18 @@ class TestGzip(BaseTest):
         # Test multiple close() calls.
         f.close()
 
+    def test_write_read_with_pathlike_file(self):
+        filename = pathlib.Path(self.filename)
+        with gzip.GzipFile(filename, 'w') as f:
+            f.write(data1 * 50)
+        self.assertIsInstance(f.name, str)
+        with gzip.GzipFile(filename, 'a') as f:
+            f.write(data1)
+        with gzip.GzipFile(filename) as f:
+            d = f.read()
+        self.assertEqual(d, data1 * 51)
+        self.assertIsInstance(f.name, str)
+
     # The following test_write_xy methods test that write accepts
     # the corresponding bytes-like object type as input
     # and that the data written equals bytes(xy) in all cases.
@@ -521,6 +534,15 @@ class TestOpen(BaseTest):
             file_data = gzip.decompress(f.read())
             self.assertEqual(file_data, uncompressed)
 
+    def test_pathlike_file(self):
+        filename = pathlib.Path(self.filename)
+        with gzip.open(filename, "wb") as f:
+            f.write(data1 * 50)
+        with gzip.open(filename, "ab") as f:
+            f.write(data1)
+        with gzip.open(filename) as f:
+            self.assertEqual(f.read(), data1 * 51)
+
     def test_implicit_binary_modes(self):
         # Test implicit binary modes (no "b" or "t" in mode string).
         uncompressed = data1 * 50