Address review feedback

Author: barneygale

Lib/pathlib/_os.py

@@ -219,7 +219,7 @@ def vfsopen(obj, mode='r', buffering=-1, encoding=None, errors=None,
     text = 'b' not in mode
     if buffering != -1:
         raise ValueError("buffer size can't be customized")
-    elif text:
+    if text:
         # Call io.text_encoding() here to ensure any warning is raised at an
         # appropriate stack level.
         encoding = text_encoding(encoding)

Lib/test/test_pathlib/test_read.py

@@ -36,6 +36,12 @@ def test_open_r(self):
             self.assertIsInstance(f, io.TextIOBase)
             self.assertEqual(f.read(), 'this is file A\n')
 
+    def test_open_r_buffering_error(self):
+        p = self.root / 'fileA'
+        self.assertRaises(ValueError, vfsopen, p, 'r', buffering=0)
+        self.assertRaises(ValueError, vfsopen, p, 'r', buffering=1)
+        self.assertRaises(ValueError, vfsopen, p, 'r', buffering=1024)
+
     @unittest.skipIf(
         not getattr(sys.flags, 'warn_default_encoding', 0),
         "Requires warn_default_encoding",

Lib/test/test_pathlib/test_write.py

@@ -36,6 +36,12 @@ def test_open_w(self):
             f.write('this is file A\n')
         self.assertEqual(self.ground.readtext(p), 'this is file A\n')
 
+    def test_open_w_buffering_error(self):
+        p = self.root / 'fileA'
+        self.assertRaises(ValueError, vfsopen, p, 'w', buffering=0)
+        self.assertRaises(ValueError, vfsopen, p, 'w', buffering=1)
+        self.assertRaises(ValueError, vfsopen, p, 'w', buffering=1024)
+
     @unittest.skipIf(
         not getattr(sys.flags, 'warn_default_encoding', 0),
         "Requires warn_default_encoding",