diff --git a/mercurial/pycompat.py b/mercurial/pycompat.py
--- a/mercurial/pycompat.py
+++ b/mercurial/pycompat.py
@@ -314,150 +314,3 @@
     stringio = cStringIO.StringIO
     maplist = map
     rawinput = raw_input
-
-class _pycompatstub(object):
-    def __init__(self):
-        self._aliases = {}
-
-    def _registeraliases(self, origin, items):
-        """Add items that will be populated at the first access"""
-        items = map(sysstr, items)
-        self._aliases.update(
-            (item.replace(sysstr('_'), sysstr('')).lower(), (origin, item))
-            for item in items)
-
-    def _registeralias(self, origin, attr, name):
-        """Alias ``origin``.``attr`` as ``name``"""
-        self._aliases[sysstr(name)] = (origin, sysstr(attr))
-
-    def __getattr__(self, name):
-        try:
-            origin, item = self._aliases[name]
-        except KeyError:
-            raise AttributeError(name)
-        self.__dict__[name] = obj = getattr(origin, item)
-        return obj
-
-httpserver = _pycompatstub()
-urlreq = _pycompatstub()
-urlerr = _pycompatstub()
-if not ispy3:
-    import BaseHTTPServer
-    import CGIHTTPServer
-    import SimpleHTTPServer
-    import urllib2
-    import urllib
-    import urlparse
-    urlreq._registeraliases(urllib, (
-        "addclosehook",
-        "addinfourl",
-        "ftpwrapper",
-        "pathname2url",
-        "quote",
-        "splitattr",
-        "splitpasswd",
-        "splitport",
-        "splituser",
-        "unquote",
-        "url2pathname",
-        "urlencode",
-    ))
-    urlreq._registeraliases(urllib2, (
-        "AbstractHTTPHandler",
-        "BaseHandler",
-        "build_opener",
-        "FileHandler",
-        "FTPHandler",
-        "HTTPBasicAuthHandler",
-        "HTTPDigestAuthHandler",
-        "HTTPHandler",
-        "HTTPPasswordMgrWithDefaultRealm",
-        "HTTPSHandler",
-        "install_opener",
-        "ProxyHandler",
-        "Request",
-        "urlopen",
-    ))
-    urlreq._registeraliases(urlparse, (
-        "urlparse",
-        "urlunparse",
-    ))
-    urlerr._registeraliases(urllib2, (
-        "HTTPError",
-        "URLError",
-    ))
-    httpserver._registeraliases(BaseHTTPServer, (
-        "HTTPServer",
-        "BaseHTTPRequestHandler",
-    ))
-    httpserver._registeraliases(SimpleHTTPServer, (
-        "SimpleHTTPRequestHandler",
-    ))
-    httpserver._registeraliases(CGIHTTPServer, (
-        "CGIHTTPRequestHandler",
-    ))
-
-else:
-    import urllib.parse
-    urlreq._registeraliases(urllib.parse, (
-        "splitattr",
-        "splitpasswd",
-        "splitport",
-        "splituser",
-        "urlparse",
-        "urlunparse",
-    ))
-    urlreq._registeralias(urllib.parse, "unquote_to_bytes", "unquote")
-    import urllib.request
-    urlreq._registeraliases(urllib.request, (
-        "AbstractHTTPHandler",
-        "BaseHandler",
-        "build_opener",
-        "FileHandler",
-        "FTPHandler",
-        "ftpwrapper",
-        "HTTPHandler",
-        "HTTPSHandler",
-        "install_opener",
-        "pathname2url",
-        "HTTPBasicAuthHandler",
-        "HTTPDigestAuthHandler",
-        "HTTPPasswordMgrWithDefaultRealm",
-        "ProxyHandler",
-        "Request",
-        "url2pathname",
-        "urlopen",
-    ))
-    import urllib.response
-    urlreq._registeraliases(urllib.response, (
-        "addclosehook",
-        "addinfourl",
-    ))
-    import urllib.error
-    urlerr._registeraliases(urllib.error, (
-        "HTTPError",
-        "URLError",
-    ))
-    import http.server
-    httpserver._registeraliases(http.server, (
-        "HTTPServer",
-        "BaseHTTPRequestHandler",
-        "SimpleHTTPRequestHandler",
-        "CGIHTTPRequestHandler",
-    ))
-
-    # urllib.parse.quote() accepts both str and bytes, decodes bytes
-    # (if necessary), and returns str. This is wonky. We provide a custom
-    # implementation that only accepts bytes and emits bytes.
-    def quote(s, safe=r'/'):
-        s = urllib.parse.quote_from_bytes(s, safe=safe)
-        return s.encode('ascii', 'strict')
-
-    # urllib.parse.urlencode() returns str. We use this function to make
-    # sure we return bytes.
-    def urlencode(query, doseq=False):
-            s = urllib.parse.urlencode(query, doseq=doseq)
-            return s.encode('ascii')
-
-    urlreq.quote = quote
-    urlreq.urlencode = urlencode
diff --git a/mercurial/urllibcompat.py b/mercurial/urllibcompat.py
--- a/mercurial/urllibcompat.py
+++ b/mercurial/urllibcompat.py
@@ -8,7 +8,99 @@
 
 from . import pycompat
 
+_sysstr = pycompat.sysstr
+
+class _pycompatstub(object):
+    def __init__(self):
+        self._aliases = {}
+
+    def _registeraliases(self, origin, items):
+        """Add items that will be populated at the first access"""
+        items = map(_sysstr, items)
+        self._aliases.update(
+            (item.replace(_sysstr('_'), _sysstr('')).lower(), (origin, item))
+            for item in items)
+
+    def _registeralias(self, origin, attr, name):
+        """Alias ``origin``.``attr`` as ``name``"""
+        self._aliases[_sysstr(name)] = (origin, _sysstr(attr))
+
+    def __getattr__(self, name):
+        try:
+            origin, item = self._aliases[name]
+        except KeyError:
+            raise AttributeError(name)
+        self.__dict__[name] = obj = getattr(origin, item)
+        return obj
+
+httpserver = _pycompatstub()
+urlreq = _pycompatstub()
+urlerr = _pycompatstub()
+
 if pycompat.ispy3:
+    import urllib.parse
+    urlreq._registeraliases(urllib.parse, (
+        "splitattr",
+        "splitpasswd",
+        "splitport",
+        "splituser",
+        "urlparse",
+        "urlunparse",
+    ))
+    urlreq._registeralias(urllib.parse, "unquote_to_bytes", "unquote")
+    import urllib.request
+    urlreq._registeraliases(urllib.request, (
+        "AbstractHTTPHandler",
+        "BaseHandler",
+        "build_opener",
+        "FileHandler",
+        "FTPHandler",
+        "ftpwrapper",
+        "HTTPHandler",
+        "HTTPSHandler",
+        "install_opener",
+        "pathname2url",
+        "HTTPBasicAuthHandler",
+        "HTTPDigestAuthHandler",
+        "HTTPPasswordMgrWithDefaultRealm",
+        "ProxyHandler",
+        "Request",
+        "url2pathname",
+        "urlopen",
+    ))
+    import urllib.response
+    urlreq._registeraliases(urllib.response, (
+        "addclosehook",
+        "addinfourl",
+    ))
+    import urllib.error
+    urlerr._registeraliases(urllib.error, (
+        "HTTPError",
+        "URLError",
+    ))
+    import http.server
+    httpserver._registeraliases(http.server, (
+        "HTTPServer",
+        "BaseHTTPRequestHandler",
+        "SimpleHTTPRequestHandler",
+        "CGIHTTPRequestHandler",
+    ))
+
+    # urllib.parse.quote() accepts both str and bytes, decodes bytes
+    # (if necessary), and returns str. This is wonky. We provide a custom
+    # implementation that only accepts bytes and emits bytes.
+    def quote(s, safe=r'/'):
+        s = urllib.parse.quote_from_bytes(s, safe=safe)
+        return s.encode('ascii', 'strict')
+
+    # urllib.parse.urlencode() returns str. We use this function to make
+    # sure we return bytes.
+    def urlencode(query, doseq=False):
+            s = urllib.parse.urlencode(query, doseq=doseq)
+            return s.encode('ascii')
+
+    urlreq.quote = quote
+    urlreq.urlencode = urlencode
 
     def getfullurl(req):
         return req.full_url
@@ -25,6 +117,60 @@
     def hasdata(req):
         return req.data is not None
 else:
+    import BaseHTTPServer
+    import CGIHTTPServer
+    import SimpleHTTPServer
+    import urllib2
+    import urllib
+    import urlparse
+    urlreq._registeraliases(urllib, (
+        "addclosehook",
+        "addinfourl",
+        "ftpwrapper",
+        "pathname2url",
+        "quote",
+        "splitattr",
+        "splitpasswd",
+        "splitport",
+        "splituser",
+        "unquote",
+        "url2pathname",
+        "urlencode",
+    ))
+    urlreq._registeraliases(urllib2, (
+        "AbstractHTTPHandler",
+        "BaseHandler",
+        "build_opener",
+        "FileHandler",
+        "FTPHandler",
+        "HTTPBasicAuthHandler",
+        "HTTPDigestAuthHandler",
+        "HTTPHandler",
+        "HTTPPasswordMgrWithDefaultRealm",
+        "HTTPSHandler",
+        "install_opener",
+        "ProxyHandler",
+        "Request",
+        "urlopen",
+    ))
+    urlreq._registeraliases(urlparse, (
+        "urlparse",
+        "urlunparse",
+    ))
+    urlerr._registeraliases(urllib2, (
+        "HTTPError",
+        "URLError",
+    ))
+    httpserver._registeraliases(BaseHTTPServer, (
+        "HTTPServer",
+        "BaseHTTPRequestHandler",
+    ))
+    httpserver._registeraliases(SimpleHTTPServer, (
+        "SimpleHTTPRequestHandler",
+    ))
+    httpserver._registeraliases(CGIHTTPServer, (
+        "CGIHTTPRequestHandler",
+    ))
 
     def gethost(req):
         return req.get_host()
diff --git a/mercurial/util.py b/mercurial/util.py
--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -50,6 +50,7 @@
     i18n,
     policy,
     pycompat,
+    urllibcompat,
 )
 
 base85 = policy.importmod(r'base85')
@@ -62,7 +63,6 @@
 cookielib = pycompat.cookielib
 empty = pycompat.empty
 httplib = pycompat.httplib
-httpserver = pycompat.httpserver
 pickle = pycompat.pickle
 queue = pycompat.queue
 socketserver = pycompat.socketserver
@@ -70,10 +70,12 @@
 stdin = pycompat.stdin
 stdout = pycompat.stdout
 stringio = pycompat.stringio
-urlerr = pycompat.urlerr
-urlreq = pycompat.urlreq
 xmlrpclib = pycompat.xmlrpclib
 
+httpserver = urllibcompat.httpserver
+urlerr = urllibcompat.urlerr
+urlreq = urllibcompat.urlreq
+
 # workaround for win32mbcs
 _filenamebytestr = pycompat.bytestr