[Python-checkins] cpython (merge 3.5 -> default): Issue #25510: fileinput.FileInput.readline() now returns b'' instead of ''

Sun Nov 1 09:46:46 EST 2015

https://hg.python.org/cpython/rev/4f0e293e6eb0
changeset: 98926:4f0e293e6eb0
parent: 98923:bd6bfa5fe203
parent: 98925:321b34824020
user: Serhiy Storchaka <storchaka at gmail.com>
date: Sun Nov 01 16:45:54 2015 +0200
summary:
 Issue #25510: fileinput.FileInput.readline() now returns b'' instead of ''
at the end if the FileInput was opened with binary mode.
Patch by Ryosuke Ito.
files:
 Lib/fileinput.py | 5 ++++-
 Lib/test/test_fileinput.py | 15 +++++++++++++++
 Misc/NEWS | 4 ++++
 3 files changed, 23 insertions(+), 1 deletions(-)

diff --git a/Lib/fileinput.py b/Lib/fileinput.py
--- a/Lib/fileinput.py
+++ b/Lib/fileinput.py
@@ -315,7 +315,10 @@
 return line
 if not self._file:
 if not self._files:
- return ""
+ if 'b' in self._mode:
+ return b''
+ else:
+ return ''
 self._filename = self._files[0]
 self._files = self._files[1:]
 self._filelineno = 0
diff --git a/Lib/test/test_fileinput.py b/Lib/test/test_fileinput.py
--- a/Lib/test/test_fileinput.py
+++ b/Lib/test/test_fileinput.py
@@ -288,6 +288,21 @@
 with self.assertRaises(UnicodeDecodeError):
 # Read to the end of file.
 list(fi)
+ self.assertEqual(fi.readline(), '')
+ self.assertEqual(fi.readline(), '')
+
+ def test_readline_binary_mode(self):
+ with open(TESTFN, 'wb') as f:
+ f.write(b'A\nB\r\nC\rD')
+ self.addCleanup(safe_unlink, TESTFN)
+
+ with FileInput(files=TESTFN, mode='rb') as fi:
+ self.assertEqual(fi.readline(), b'A\n')
+ self.assertEqual(fi.readline(), b'B\r\n')
+ self.assertEqual(fi.readline(), b'C\rD')
+ # Read to the end of file.
+ self.assertEqual(fi.readline(), b'')
+ self.assertEqual(fi.readline(), b'')
 
 def test_context_manager(self):
 try:
diff --git a/Misc/NEWS b/Misc/NEWS
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -66,6 +66,10 @@
 Library
 -------
 
+- Issue #25510: fileinput.FileInput.readline() now returns b'' instead of ''
+ at the end if the FileInput was opened with binary mode.
+ Patch by Ryosuke Ito.
+
 - Issue #25503: Fixed inspect.getdoc() for inherited docstrings of properties.
 Original patch by John Mark Vandenberg.
 
-- 
Repository URL: https://hg.python.org/cpython
