commit 3b3be1fe10f6c15e57360cac9d9dbc660666e655
author Miss Islington (bot) <31488909+miss-islington@users.noreply.github.com> Tue Apr 17 14:58:34 2018 -0700
committer GitHub <noreply@github.com> Tue Apr 17 14:58:34 2018 -0700
tree b7bce74cd03b91a1ab688465d708d236b95f0ba7
parent 902bb62d5af21526b68892a1032c63aa86ded247

bpo-11594: Ensure line-endings are respected when using 2to3 (GH-6483)

(cherry picked from commit c127a86e1862df88ec6f9d15b79c627fc616766e)

Co-authored-by: Aaron Ang <aaronang@users.noreply.github.com>

Lib/lib2to3/refactor.py

diff --git a/Lib/lib2to3/refactor.py b/Lib/lib2to3/refactor.py
index db2e38d..7c4e064 100644
--- a/Lib/lib2to3/refactor.py
+++ b/Lib/lib2to3/refactor.py
@@ -314,7 +314,7 @@
             encoding = tokenize.detect_encoding(f.readline)[0]
         finally:
             f.close()
-        with io.open(filename, "r", encoding=encoding) as f:
+        with io.open(filename, "r", encoding=encoding, newline='') as f:
             return f.read(), encoding
 
     def refactor_file(self, filename, write=False, doctests_only=False):