Merge: #14645: Generator now emits correct linesep for all parts.

Previously the parts of the message retained whatever linesep they had on
read, which means if the messages weren't read in univeral newline mode, the
line endings could well be inconsistent.  In general sending it via smtplib
would result in them getting fixed, but it is better to generate them
correctly to begin with.  Also, the new send_message method of smtplib does
not do the fixup, so that method is producing rfc-invalid output without this
fix.

1 files changed, 34 insertions, 0 deletions

diff --git a/Lib/test/test_email/test_email.py b/Lib/test/test_email/test_email.py
index 593d27b..dd54a1c 100644
--- a/Lib/test/test_email/test_email.py
+++ b/Lib/test/test_email/test_email.py
@@ -3111,6 +3111,40 @@ multipart/report
             email.utils.make_msgid(domain='testdomain-string')[-19:],
             '@testdomain-string>')
 
+    def test_Generator_linend(self):
+        # Issue 14645.
+        with openfile('msg_26.txt', newline='\n') as f:
+            msgtxt = f.read()
+        msgtxt_nl = msgtxt.replace('\r\n', '\n')
+        msg = email.message_from_string(msgtxt)
+        s = StringIO()
+        g = email.generator.Generator(s)
+        g.flatten(msg)
+        self.assertEqual(s.getvalue(), msgtxt_nl)
+
+    def test_BytesGenerator_linend(self):
+        # Issue 14645.
+        with openfile('msg_26.txt', newline='\n') as f:
+            msgtxt = f.read()
+        msgtxt_nl = msgtxt.replace('\r\n', '\n')
+        msg = email.message_from_string(msgtxt_nl)
+        s = BytesIO()
+        g = email.generator.BytesGenerator(s)
+        g.flatten(msg, linesep='\r\n')
+        self.assertEqual(s.getvalue().decode('ascii'), msgtxt)
+
+    def test_BytesGenerator_linend_with_non_ascii(self):
+        # Issue 14645.
+        with openfile('msg_26.txt', 'rb') as f:
+            msgtxt = f.read()
+        msgtxt = msgtxt.replace(b'with attachment', b'fo\xf6')
+        msgtxt_nl = msgtxt.replace(b'\r\n', b'\n')
+        msg = email.message_from_bytes(msgtxt_nl)
+        s = BytesIO()
+        g = email.generator.BytesGenerator(s)
+        g.flatten(msg, linesep='\r\n')
+        self.assertEqual(s.getvalue(), msgtxt)
+
 
 # Test the iterator/generators
 class TestIterators(TestEmailBase):