commit ea9835c5d154ab6a54eed627958473b6768b28cc
author Inada Naoki <songofacandy@gmail.com> Wed Nov 27 22:22:06 2019 +0900
committer GitHub <noreply@github.com> Wed Nov 27 22:22:06 2019 +0900
tree e65f74eab9ca75f936121582111232d970aa159c
parent 1bddf890e595a865414645c6041733043c4081f8

bpo-26730: Fix SpooledTemporaryFile data corruption (GH-17400)

SpooledTemporaryFile.rollback() might cause data corruption
when it is in text mode.

Co-Authored-By: Serhiy Storchaka <storchaka@gmail.com>

Lib/test/test_tempfile.py

diff --git a/Lib/test/test_tempfile.py b/Lib/test/test_tempfile.py
index f995f6c..232c5da 100644
--- a/Lib/test/test_tempfile.py
+++ b/Lib/test/test_tempfile.py
@@ -1114,7 +1114,8 @@
     def test_text_mode(self):
         # Creating a SpooledTemporaryFile with a text mode should produce
         # a file object reading and writing (Unicode) text strings.
-        f = tempfile.SpooledTemporaryFile(mode='w+', max_size=10)
+        f = tempfile.SpooledTemporaryFile(mode='w+', max_size=10,
+                                          encoding="utf-8")
         f.write("abc\n")
         f.seek(0)
         self.assertEqual(f.read(), "abc\n")
@@ -1124,9 +1125,9 @@
         self.assertFalse(f._rolled)
         self.assertEqual(f.mode, 'w+')
         self.assertIsNone(f.name)
-        self.assertIsNone(f.newlines)
-        self.assertIsNone(f.encoding)
-        self.assertIsNone(f.errors)
+        self.assertEqual(f.newlines, os.linesep)
+        self.assertEqual(f.encoding, "utf-8")
+        self.assertEqual(f.errors, "strict")
 
         f.write("xyzzy\n")
         f.seek(0)
@@ -1139,8 +1140,8 @@
         self.assertEqual(f.mode, 'w+')
         self.assertIsNotNone(f.name)
         self.assertEqual(f.newlines, os.linesep)
-        self.assertIsNotNone(f.encoding)
-        self.assertIsNotNone(f.errors)
+        self.assertEqual(f.encoding, "utf-8")
+        self.assertEqual(f.errors, "strict")
 
     def test_text_newline_and_encoding(self):
         f = tempfile.SpooledTemporaryFile(mode='w+', max_size=10,
@@ -1152,13 +1153,15 @@
         self.assertFalse(f._rolled)
         self.assertEqual(f.mode, 'w+')
         self.assertIsNone(f.name)
-        self.assertIsNone(f.newlines)
-        self.assertIsNone(f.encoding)
-        self.assertIsNone(f.errors)
+        self.assertIsNotNone(f.newlines)
+        self.assertEqual(f.encoding, "utf-8")
+        self.assertEqual(f.errors, "ignore")
 
-        f.write("\u039B" * 20 + "\r\n")
+        f.write("\u039C" * 10 + "\r\n")
+        f.write("\u039D" * 20)
         f.seek(0)
-        self.assertEqual(f.read(), "\u039B\r\n" + ("\u039B" * 20) + "\r\n")
+        self.assertEqual(f.read(),
+                "\u039B\r\n" + ("\u039C" * 10) + "\r\n" + ("\u039D" * 20))
         self.assertTrue(f._rolled)
         self.assertEqual(f.mode, 'w+')
         self.assertIsNotNone(f.name)