From 05b7631c17670a5b221f88161aad23c741b5be79 Mon Sep 17 00:00:00 2001
From: "R. David Murray" <rdmurray@bitdance.com>
Date: Sat, 17 Jul 2010 01:35:16 +0000
Subject: [PATCH] Merged revisions 82922 via svnmerge from
 svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r82922 | r.david.murray | 2010-07-16 21:19:57 -0400 (Fri, 16 Jul 2010) | 4 lines

  #1555570: correctly handle a \r\n that is split by the read buffer.

  Patch and test by Tony Nelson.
........
---
 Lib/email/feedparser.py      |  4 ++++
 Lib/email/test/test_email.py | 33 +++++++++++++++++++++++++++++++++
 Misc/NEWS                    |  2 ++
 3 files changed, 39 insertions(+)

diff --git a/Lib/email/feedparser.py b/Lib/email/feedparser.py
index 163fadafd4a..5ff266fa30a 100644
--- a/Lib/email/feedparser.py
+++ b/Lib/email/feedparser.py
@@ -104,6 +104,10 @@ class BufferedSubFile(object):
         # data after the final RE.  In the case of a NL/CR terminated string,
         # this is the empty string.
         self._partial = parts.pop()
+        #GAN 29Mar09  bugs 1555570, 1721862  Confusion at 8K boundary ending with \r:
+        # is there a \n to follow later?
+        if not self._partial and parts and parts[-1].endswith('\r'):
+            self._partial = parts.pop(-2)+parts.pop()
         # parts is a list of strings, alternating between the line contents
         # and the eol character(s).  Gather up a list of lines after
         # re-attaching the newlines.
diff --git a/Lib/email/test/test_email.py b/Lib/email/test/test_email.py
index 4ce98481369..067937a9757 100644
--- a/Lib/email/test/test_email.py
+++ b/Lib/email/test/test_email.py
@@ -2465,6 +2465,39 @@ Do you like this message?
 -Me
 """)
 
+    def test_pushCR_LF(self):
+        '''FeedParser BufferedSubFile.push() assumed it received complete
+           line endings.  A CR ending one push() followed by a LF starting
+           the next push() added an empty line.
+        '''
+        imt = [
+            ("a\r \n",  2),
+            ("b",       0),
+            ("c\n",     1),
+            ("",        0),
+            ("d\r\n",   1),
+            ("e\r",     0),
+            ("\nf",     1),
+            ("\r\n",    1),
+          ]
+        from email.feedparser import BufferedSubFile, NeedMoreData
+        bsf = BufferedSubFile()
+        om = []
+        nt = 0
+        for il, n in imt:
+            bsf.push(il)
+            nt += n
+            n1 = 0
+            while True:
+                ol = bsf.readline()
+                if ol == NeedMoreData:
+                    break
+                om.append(ol)
+                n1 += 1
+            self.assertTrue(n == n1)
+        self.assertTrue(len(om) == nt)
+        self.assertTrue(''.join([il for il, n in imt]) == ''.join(om))
+
 
 
 class TestParsers(TestEmailBase):
diff --git a/Misc/NEWS b/Misc/NEWS
index bc48622e21d..17fb0724adb 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -833,6 +833,8 @@ Core and Builtins
 
 Library
 -------
+- Issue #1555570: email no longer inserts extra blank lines when a \r\n
+  combo crosses an 8192 byte boundary.
 
 - Issue #6906: Tk should not set Unicode environment variables on Windows.