From 131a489903cd03706c3cc571b94ea702e0f29c2e Mon Sep 17 00:00:00 2001
From: Antoine Pitrou <solipsis@pitrou.net>
Date: Tue, 16 Oct 2012 22:57:11 +0200
Subject: [PATCH 1/2] Add tests for the writelines() method of file objects.
 Original patch by Felipe Cruz.

---
 Lib/test/test_fileio.py | 22 ++++++++++++++++++++++
 Lib/test/test_io.py     | 25 ++++++++++++++++++++++++-
 2 files changed, 46 insertions(+), 1 deletion(-)

diff --git a/Lib/test/test_fileio.py b/Lib/test/test_fileio.py
index 5504ea321b5..b5bd8d45ad8 100644
--- a/Lib/test/test_fileio.py
+++ b/Lib/test/test_fileio.py
@@ -9,6 +9,7 @@ from weakref import proxy
 from functools import wraps
 
 from test.support import TESTFN, check_warnings, run_unittest, make_bad_fd
+from collections import UserList
 
 from _io import FileIO as _FileIO
 
@@ -67,6 +68,27 @@ class AutoFileTests(unittest.TestCase):
         n = self.f.readinto(a)
         self.assertEqual(array('b', [1, 2]), a[:n])
 
+    def testWritelinesList(self):
+        l = [b'123', b'456']
+        self.f.writelines(l)
+        self.f.close()
+        self.f = _FileIO(TESTFN, 'rb')
+        buf = self.f.read()
+        self.assertEqual(buf, b'123456')
+
+    def testWritelinesUserList(self):
+        l = UserList([b'123', b'456'])
+        self.f.writelines(l)
+        self.f.close()
+        self.f = _FileIO(TESTFN, 'rb')
+        buf = self.f.read()
+        self.assertEqual(buf, b'123456')
+
+    def testWritelinesError(self):
+        self.assertRaises(TypeError, self.f.writelines, [1, 2, 3])
+        self.assertRaises(TypeError, self.f.writelines, None)
+        self.assertRaises(TypeError, self.f.writelines, "abc")
+
     def test_none_args(self):
         self.f.write(b"hi\nbye\nabc")
         self.f.close()
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 0c3e0b88d81..6fc3c734b87 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -32,7 +32,7 @@ import errno
 import warnings
 import pickle
 from itertools import cycle, count
-from collections import deque
+from collections import deque, UserList
 from test import support
 
 import codecs
@@ -1177,6 +1177,29 @@ class BufferedWriterTest(unittest.TestCase, CommonBufferedTests):
         bufio.flush()
         self.assertEqual(b"abc", writer._write_stack[0])
 
+    def test_writelines(self):
+        l = [b'ab', b'cd', b'ef']
+        writer = self.MockRawIO()
+        bufio = self.tp(writer, 8)
+        bufio.writelines(l)
+        bufio.flush()
+        self.assertEqual(b''.join(writer._write_stack), b'abcdef')
+
+    def test_writelines_userlist(self):
+        l = UserList([b'ab', b'cd', b'ef'])
+        writer = self.MockRawIO()
+        bufio = self.tp(writer, 8)
+        bufio.writelines(l)
+        bufio.flush()
+        self.assertEqual(b''.join(writer._write_stack), b'abcdef')
+
+    def test_writelines_error(self):
+        writer = self.MockRawIO()
+        bufio = self.tp(writer, 8)
+        self.assertRaises(TypeError, bufio.writelines, [1, 2, 3])
+        self.assertRaises(TypeError, bufio.writelines, None)
+        self.assertRaises(TypeError, bufio.writelines, 'abc')
+
     def test_destructor(self):
         writer = self.MockRawIO()
         bufio = self.tp(writer, 8)

From 3ed2cb5520fe1ad05664db41f7bac96438efc7d2 Mon Sep 17 00:00:00 2001
From: Antoine Pitrou <solipsis@pitrou.net>
Date: Tue, 16 Oct 2012 23:02:27 +0200
Subject: [PATCH 2/2] Also add tests for TextIOWrapper.writelines() (issue
 #15744).

---
 Lib/test/test_io.py | 22 ++++++++++++++++++++++
 1 file changed, 22 insertions(+)

diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 6fc3c734b87..56ac2c8a792 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -2287,6 +2287,28 @@ class TextIOWrapperTest(unittest.TestCase):
             reads += c
         self.assertEqual(reads, "A"*127+"\nB")
 
+    def test_writelines(self):
+        l = ['ab', 'cd', 'ef']
+        buf = self.BytesIO()
+        txt = self.TextIOWrapper(buf)
+        txt.writelines(l)
+        txt.flush()
+        self.assertEqual(buf.getvalue(), b'abcdef')
+
+    def test_writelines_userlist(self):
+        l = UserList(['ab', 'cd', 'ef'])
+        buf = self.BytesIO()
+        txt = self.TextIOWrapper(buf)
+        txt.writelines(l)
+        txt.flush()
+        self.assertEqual(buf.getvalue(), b'abcdef')
+
+    def test_writelines_error(self):
+        txt = self.TextIOWrapper(self.BytesIO())
+        self.assertRaises(TypeError, txt.writelines, [1, 2, 3])
+        self.assertRaises(TypeError, txt.writelines, None)
+        self.assertRaises(TypeError, txt.writelines, b'abc')
+
     def test_issue1395_1(self):
         txt = self.TextIOWrapper(self.BytesIO(self.testdata), encoding="ascii")