[PATCH] py3: use email.parser module to parse email messages

[Pulkit Goyal]

# HG changeset patch
# User Pulkit Goyal <7895pulkit at gmail.com>
# Date 1514573036 -19800
#      Sat Dec 30 00:13:56 2017 +0530
# Node ID 9c8cc14cd05fa3420b1549c5369bf9b3623bd5ee
# Parent  390f860228ba909499093e0e8861c908fe15a2d0
# EXP-Topic py3
py3: use email.parser module to parse email messages

Before this patch we use email.Parser.Parser() from the email module which is
not available on Python 3.

On Python 2:

>>> import email
>>> import email.parser as emailparser
>>> email.Parser.Parser is emailparser.Parser
True

diff --git a/hgext/convert/gnuarch.py b/hgext/convert/gnuarch.py
--- a/hgext/convert/gnuarch.py
+++ b/hgext/convert/gnuarch.py
@@ -7,7 +7,7 @@
 # GNU General Public License version 2 or any later version.
 from __future__ import absolute_import
 
-import email
+import email.parser as emailparser
 import os
 import shutil
 import stat
@@ -63,7 +63,7 @@
         self.changes = {}
         self.parents = {}
         self.tags = {}
-        self.catlogparser = email.Parser.Parser()
+        self.catlogparser = emailparser.Parser()
         self.encoding = encoding.encoding
         self.archives = []
 
diff --git a/hgext/notify.py b/hgext/notify.py
--- a/hgext/notify.py
+++ b/hgext/notify.py
@@ -135,6 +135,7 @@
 from __future__ import absolute_import
 
 import email
+import email.parser as emailparser
 import fnmatch
 import socket
 import time
@@ -339,7 +340,7 @@
                           'and revset\n')
             return
 
-        p = email.Parser.Parser()
+        p = emailparser.Parser()
         try:
             msg = p.parsestr(data)
         except email.Errors.MessageParseError as inst:
diff --git a/mercurial/patch.py b/mercurial/patch.py
--- a/mercurial/patch.py
+++ b/mercurial/patch.py
@@ -12,6 +12,7 @@
 import copy
 import difflib
 import email
+import email.parser as emailparser
 import errno
 import hashlib
 import os
@@ -108,7 +109,7 @@
             cur.append(line)
         c = chunk(cur)
 
-        m = email.Parser.Parser().parse(c)
+        m = emailparser.Parser().parse(c)
         if not m.is_multipart():
             yield msgfp(m)
         else:
@@ -217,7 +218,7 @@
     fd, tmpname = tempfile.mkstemp(prefix='hg-patch-')
     tmpfp = os.fdopen(fd, pycompat.sysstr('w'))
     try:
-        msg = email.Parser.Parser().parse(fileobj)
+        msg = emailparser.Parser().parse(fileobj)
 
         subject = msg['Subject'] and mail.headdecode(msg['Subject'])
         data['user'] = msg['From'] and mail.headdecode(msg['From'])