Jason Mastaler's patch to break the dependence on rfc822.py for the
address parsing routines.  Closes SF patch #613434.
diff --git a/Lib/email/_parseaddr.py b/Lib/email/_parseaddr.py
new file mode 100644
index 0000000..cb2869a
--- /dev/null
+++ b/Lib/email/_parseaddr.py
@@ -0,0 +1,441 @@
+# Copyright (C) 2002 Python Software Foundation
+
+"""Email address parsing code.
+
+Lifted directly from rfc822.py.  This should eventually be rewritten.
+"""
+
+import time
+
+# Parse a date field
+_monthnames = ['jan', 'feb', 'mar', 'apr', 'may', 'jun', 'jul',
+               'aug', 'sep', 'oct', 'nov', 'dec',
+               'january', 'february', 'march', 'april', 'may', 'june', 'july',
+               'august', 'september', 'october', 'november', 'december']
+
+_daynames = ['mon', 'tue', 'wed', 'thu', 'fri', 'sat', 'sun']
+
+# The timezone table does not include the military time zones defined
+# in RFC822, other than Z.  According to RFC1123, the description in
+# RFC822 gets the signs wrong, so we can't rely on any such time
+# zones.  RFC1123 recommends that numeric timezone indicators be used
+# instead of timezone names.
+
+_timezones = {'UT':0, 'UTC':0, 'GMT':0, 'Z':0,
+              'AST': -400, 'ADT': -300,  # Atlantic (used in Canada)
+              'EST': -500, 'EDT': -400,  # Eastern
+              'CST': -600, 'CDT': -500,  # Central
+              'MST': -700, 'MDT': -600,  # Mountain
+              'PST': -800, 'PDT': -700   # Pacific
+              }
+
+
+def parsedate_tz(data):
+    """Convert a date string to a time tuple.
+
+    Accounts for military timezones.
+    """
+    data = data.split()
+    if data[0][-1] in (',', '.') or data[0].lower() in _daynames:
+        # There's a dayname here. Skip it
+        del data[0]
+    if len(data) == 3: # RFC 850 date, deprecated
+        stuff = data[0].split('-')
+        if len(stuff) == 3:
+            data = stuff + data[1:]
+    if len(data) == 4:
+        s = data[3]
+        i = s.find('+')
+        if i > 0:
+            data[3:] = [s[:i], s[i+1:]]
+        else:
+            data.append('') # Dummy tz
+    if len(data) < 5:
+        return None
+    data = data[:5]
+    [dd, mm, yy, tm, tz] = data
+    mm = mm.lower()
+    if not mm in _monthnames:
+        dd, mm = mm, dd.lower()
+        if not mm in _monthnames:
+            return None
+    mm = _monthnames.index(mm)+1
+    if mm > 12: mm = mm - 12
+    if dd[-1] == ',':
+        dd = dd[:-1]
+    i = yy.find(':')
+    if i > 0:
+        yy, tm = tm, yy
+    if yy[-1] == ',':
+        yy = yy[:-1]
+    if not yy[0].isdigit():
+        yy, tz = tz, yy
+    if tm[-1] == ',':
+        tm = tm[:-1]
+    tm = tm.split(':')
+    if len(tm) == 2:
+        [thh, tmm] = tm
+        tss = '0'
+    elif len(tm) == 3:
+        [thh, tmm, tss] = tm
+    else:
+        return None
+    try:
+        yy = int(yy)
+        dd = int(dd)
+        thh = int(thh)
+        tmm = int(tmm)
+        tss = int(tss)
+    except ValueError:
+        return None
+    tzoffset = None
+    tz = tz.upper()
+    if _timezones.has_key(tz):
+        tzoffset = _timezones[tz]
+    else:
+        try:
+            tzoffset = int(tz)
+        except ValueError:
+            pass
+    # Convert a timezone offset into seconds ; -0500 -> -18000
+    if tzoffset:
+        if tzoffset < 0:
+            tzsign = -1
+            tzoffset = -tzoffset
+        else:
+            tzsign = 1
+        tzoffset = tzsign * ( (tzoffset/100)*3600 + (tzoffset % 100)*60)
+    tuple = (yy, mm, dd, thh, tmm, tss, 0, 0, 0, tzoffset)
+    return tuple
+
+
+def parsedate(data):
+    """Convert a time string to a time tuple."""
+    t = parsedate_tz(data)
+    if type(t) == type( () ):
+        return t[:9]
+    else: return t
+
+
+def mktime_tz(data):
+    """Turn a 10-tuple as returned by parsedate_tz() into a UTC timestamp."""
+    if data[9] is None:
+        # No zone info, so localtime is better assumption than GMT
+        return time.mktime(data[:8] + (-1,))
+    else:
+        t = time.mktime(data[:8] + (0,))
+        return t - data[9] - time.timezone
+
+
+def quote(str):
+    """Add quotes around a string."""
+    return str.replace('\\', '\\\\').replace('"', '\\"')
+
+
+class AddrlistClass:
+    """Address parser class by Ben Escoto.
+
+    To understand what this class does, it helps to have a copy of
+    RFC-822 in front of you.
+
+    Note: this class interface is deprecated and may be removed in the future.
+    Use rfc822.AddressList instead.
+    """
+
+    def __init__(self, field):
+        """Initialize a new instance.
+
+        `field' is an unparsed address header field, containing
+        one or more addresses.
+        """
+        self.specials = '()<>@,:;.\"[]'
+        self.pos = 0
+        self.LWS = ' \t'
+        self.CR = '\r\n'
+        self.atomends = self.specials + self.LWS + self.CR
+        self.field = field
+        self.commentlist = []
+
+    def gotonext(self):
+        """Parse up to the start of the next address."""
+        while self.pos < len(self.field):
+            if self.field[self.pos] in self.LWS + '\n\r':
+                self.pos = self.pos + 1
+            elif self.field[self.pos] == '(':
+                self.commentlist.append(self.getcomment())
+            else: break
+
+    def getaddrlist(self):
+        """Parse all addresses.
+
+        Returns a list containing all of the addresses.
+        """
+        ad = self.getaddress()
+        if ad:
+            return ad + self.getaddrlist()
+        else: return []
+
+    def getaddress(self):
+        """Parse the next address."""
+        self.commentlist = []
+        self.gotonext()
+
+        oldpos = self.pos
+        oldcl = self.commentlist
+        plist = self.getphraselist()
+
+        self.gotonext()
+        returnlist = []
+
+        if self.pos >= len(self.field):
+            # Bad email address technically, no domain.
+            if plist:
+                returnlist = [(' '.join(self.commentlist), plist[0])]
+
+        elif self.field[self.pos] in '.@':
+            # email address is just an addrspec
+            # this isn't very efficient since we start over
+            self.pos = oldpos
+            self.commentlist = oldcl
+            addrspec = self.getaddrspec()
+            returnlist = [(' '.join(self.commentlist), addrspec)]
+
+        elif self.field[self.pos] == ':':
+            # address is a group
+            returnlist = []
+
+            fieldlen = len(self.field)
+            self.pos = self.pos + 1
+            while self.pos < len(self.field):
+                self.gotonext()
+                if self.pos < fieldlen and self.field[self.pos] == ';':
+                    self.pos = self.pos + 1
+                    break
+                returnlist = returnlist + self.getaddress()
+
+        elif self.field[self.pos] == '<':
+            # Address is a phrase then a route addr
+            routeaddr = self.getrouteaddr()
+
+            if self.commentlist:
+                returnlist = [(' '.join(plist) + ' (' + \
+                         ' '.join(self.commentlist) + ')', routeaddr)]
+            else: returnlist = [(' '.join(plist), routeaddr)]
+
+        else:
+            if plist:
+                returnlist = [(' '.join(self.commentlist), plist[0])]
+            elif self.field[self.pos] in self.specials:
+                self.pos = self.pos + 1
+
+        self.gotonext()
+        if self.pos < len(self.field) and self.field[self.pos] == ',':
+            self.pos = self.pos + 1
+        return returnlist
+
+    def getrouteaddr(self):
+        """Parse a route address (Return-path value).
+
+        This method just skips all the route stuff and returns the addrspec.
+        """
+        if self.field[self.pos] != '<':
+            return
+
+        expectroute = 0
+        self.pos = self.pos + 1
+        self.gotonext()
+        adlist = ""
+        while self.pos < len(self.field):
+            if expectroute:
+                self.getdomain()
+                expectroute = 0
+            elif self.field[self.pos] == '>':
+                self.pos = self.pos + 1
+                break
+            elif self.field[self.pos] == '@':
+                self.pos = self.pos + 1
+                expectroute = 1
+            elif self.field[self.pos] == ':':
+                self.pos = self.pos + 1
+                expectaddrspec = 1
+            else:
+                adlist = self.getaddrspec()
+                self.pos = self.pos + 1
+                break
+            self.gotonext()
+
+        return adlist
+
+    def getaddrspec(self):
+        """Parse an RFC-822 addr-spec."""
+        aslist = []
+
+        self.gotonext()
+        while self.pos < len(self.field):
+            if self.field[self.pos] == '.':
+                aslist.append('.')
+                self.pos = self.pos + 1
+            elif self.field[self.pos] == '"':
+                aslist.append('"%s"' % self.getquote())
+            elif self.field[self.pos] in self.atomends:
+                break
+            else: aslist.append(self.getatom())
+            self.gotonext()
+
+        if self.pos >= len(self.field) or self.field[self.pos] != '@':
+            return ''.join(aslist)
+
+        aslist.append('@')
+        self.pos = self.pos + 1
+        self.gotonext()
+        return ''.join(aslist) + self.getdomain()
+
+    def getdomain(self):
+        """Get the complete domain name from an address."""
+        sdlist = []
+        while self.pos < len(self.field):
+            if self.field[self.pos] in self.LWS:
+                self.pos = self.pos + 1
+            elif self.field[self.pos] == '(':
+                self.commentlist.append(self.getcomment())
+            elif self.field[self.pos] == '[':
+                sdlist.append(self.getdomainliteral())
+            elif self.field[self.pos] == '.':
+                self.pos = self.pos + 1
+                sdlist.append('.')
+            elif self.field[self.pos] in self.atomends:
+                break
+            else: sdlist.append(self.getatom())
+        return ''.join(sdlist)
+
+    def getdelimited(self, beginchar, endchars, allowcomments = 1):
+        """Parse a header fragment delimited by special characters.
+
+        `beginchar' is the start character for the fragment.
+        If self is not looking at an instance of `beginchar' then
+        getdelimited returns the empty string.
+
+        `endchars' is a sequence of allowable end-delimiting characters.
+        Parsing stops when one of these is encountered.
+
+        If `allowcomments' is non-zero, embedded RFC-822 comments
+        are allowed within the parsed fragment.
+        """
+        if self.field[self.pos] != beginchar:
+            return ''
+
+        slist = ['']
+        quote = 0
+        self.pos = self.pos + 1
+        while self.pos < len(self.field):
+            if quote == 1:
+                slist.append(self.field[self.pos])
+                quote = 0
+            elif self.field[self.pos] in endchars:
+                self.pos = self.pos + 1
+                break
+            elif allowcomments and self.field[self.pos] == '(':
+                slist.append(self.getcomment())
+            elif self.field[self.pos] == '\\':
+                quote = 1
+            else:
+                slist.append(self.field[self.pos])
+            self.pos = self.pos + 1
+
+        return ''.join(slist)
+
+    def getquote(self):
+        """Get a quote-delimited fragment from self's field."""
+        return self.getdelimited('"', '"\r', 0)
+
+    def getcomment(self):
+        """Get a parenthesis-delimited fragment from self's field."""
+        return self.getdelimited('(', ')\r', 1)
+
+    def getdomainliteral(self):
+        """Parse an RFC-822 domain-literal."""
+        return '[%s]' % self.getdelimited('[', ']\r', 0)
+
+    def getatom(self):
+        """Parse an RFC-822 atom."""
+        atomlist = ['']
+
+        while self.pos < len(self.field):
+            if self.field[self.pos] in self.atomends:
+                break
+            else: atomlist.append(self.field[self.pos])
+            self.pos = self.pos + 1
+
+        return ''.join(atomlist)
+
+    def getphraselist(self):
+        """Parse a sequence of RFC-822 phrases.
+
+        A phrase is a sequence of words, which are in turn either
+        RFC-822 atoms or quoted-strings.  Phrases are canonicalized
+        by squeezing all runs of continuous whitespace into one space.
+        """
+        plist = []
+
+        while self.pos < len(self.field):
+            if self.field[self.pos] in self.LWS:
+                self.pos = self.pos + 1
+            elif self.field[self.pos] == '"':
+                plist.append(self.getquote())
+            elif self.field[self.pos] == '(':
+                self.commentlist.append(self.getcomment())
+            elif self.field[self.pos] in self.atomends:
+                break
+            else: plist.append(self.getatom())
+
+        return plist
+
+class AddressList(AddrlistClass):
+    """An AddressList encapsulates a list of parsed RFC822 addresses."""
+    def __init__(self, field):
+        AddrlistClass.__init__(self, field)
+        if field:
+            self.addresslist = self.getaddrlist()
+        else:
+            self.addresslist = []
+
+    def __len__(self):
+        return len(self.addresslist)
+
+    def __str__(self):
+        return ", ".join(map(dump_address_pair, self.addresslist))
+
+    def __add__(self, other):
+        # Set union
+        newaddr = AddressList(None)
+        newaddr.addresslist = self.addresslist[:]
+        for x in other.addresslist:
+            if not x in self.addresslist:
+                newaddr.addresslist.append(x)
+        return newaddr
+
+    def __iadd__(self, other):
+        # Set union, in-place
+        for x in other.addresslist:
+            if not x in self.addresslist:
+                self.addresslist.append(x)
+        return self
+
+    def __sub__(self, other):
+        # Set difference
+        newaddr = AddressList(None)
+        for x in self.addresslist:
+            if not x in other.addresslist:
+                newaddr.addresslist.append(x)
+        return newaddr
+
+    def __isub__(self, other):
+        # Set difference, in-place
+        for x in other.addresslist:
+            if x in self.addresslist:
+                self.addresslist.remove(x)
+        return self
+
+    def __getitem__(self, index):
+        # Make indexing, slices, and 'in' work
+        return self.addresslist[index]