diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -1484,7 +1484,7 @@ def help_(ui, name=None, with_version=Fa
                 ui.write(' %-*s   %s\n' % (m, f, h[f]))
 
         if name != 'shortlist':
-            exts, maxlength = help.enabledextensions()
+            exts, maxlength = extensions.enabled()
             ui.write(help.extensionslisting(_('enabled extensions:'),
                                             exts, maxlength))
 
diff --git a/mercurial/extensions.py b/mercurial/extensions.py
--- a/mercurial/extensions.py
+++ b/mercurial/extensions.py
@@ -5,9 +5,9 @@
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2, incorporated herein by reference.
 
-import imp, os
-import util, cmdutil
-from i18n import _
+import imp, os, sys
+import util, cmdutil, help
+from i18n import _, gettext
 
 _extensions = {}
 _order = []
@@ -117,3 +117,75 @@ def wrapfunction(container, funcname, wr
     origfn = getattr(container, funcname)
     setattr(container, funcname, wrap)
     return origfn
+
+def pathdirs():
+    '''convert sys.path into a list of absolute, existing, unique paths
+    (taken from pydoc)'''
+    dirs = []
+    normdirs = []
+    for dir in sys.path:
+        dir = os.path.abspath(dir or '.')
+        normdir = os.path.normcase(dir)
+        if normdir not in normdirs and os.path.isdir(dir):
+            dirs.append(dir)
+            normdirs.append(normdir)
+    return dirs
+
+def disabled():
+    '''find disabled extensions from hgext
+    returns a dict of {name: desc}, and the max name length'''
+    exts = {}
+    maxlength = 0
+    for dir in filter(os.path.isdir,
+                      (os.path.join(pd, 'hgext') for pd in pathdirs())):
+        for e in os.listdir(dir):
+            if e.endswith('.py'):
+                name = e.rsplit('.', 1)[0]
+                path = os.path.join(dir, e)
+            else:
+                name = e
+                path = os.path.join(dir, e, '__init__.py')
+
+            if name in exts or name == '__init__' or not os.path.exists(path):
+                continue
+
+            try:
+                find(name)
+            except KeyError:
+                pass
+            else:
+                continue # enabled extension
+
+            try:
+                file = open(path)
+            except IOError:
+                continue
+            else:
+                doc = help.moduledoc(file)
+                file.close()
+
+            if doc: # extracting localized synopsis
+                exts[name] = gettext(doc).splitlines()[0]
+            else:
+                exts[name] = _('(no help text available)')
+            if len(name) > maxlength:
+                maxlength = len(name)
+
+    return exts, maxlength
+
+def enabled():
+    '''return a dict of {name: desc} of extensions, and the max name length'''
+
+    if not enabled:
+        return {}, 0
+
+    exts = {}
+    maxlength = 0
+    exthelps = []
+    for ename, ext in extensions():
+        doc = (gettext(ext.__doc__) or _('(no help text available)'))
+        ename = ename.split('.')[-1]
+        maxlength = max(len(ename), maxlength)
+        exts[ename] = doc.splitlines(0)[0].strip()
+
+    return exts, maxlength
diff --git a/mercurial/help.py b/mercurial/help.py
--- a/mercurial/help.py
+++ b/mercurial/help.py
@@ -5,24 +5,10 @@
 # This software may be used and distributed according to the terms of the
 # GNU General Public License version 2, incorporated herein by reference.
 
-import os, sys
-from i18n import _, gettext
+from i18n import _
 import extensions
 
 
-# borrowed from pydoc
-def pathdirs():
-    '''Convert sys.path into a list of absolute, existing, unique paths.'''
-    dirs = []
-    normdirs = []
-    for dir in sys.path:
-        dir = os.path.abspath(dir or '.')
-        normdir = os.path.normcase(dir)
-        if normdir not in normdirs and os.path.isdir(dir):
-            dirs.append(dir)
-            normdirs.append(normdir)
-    return dirs
-
 # loosely inspired by pydoc.source_synopsis()
 # rewritten to handle ''' as well as """
 # and to return the whole text instead of just the synopsis
@@ -53,67 +39,6 @@ def moduledoc(file):
 
     return ''.join(result)
 
-def additionalextensions():
-    '''Find the extensions shipped with Mercurial but not enabled
-
-    Returns extensions names and descriptions, and the max name length
-    '''
-    exts = {}
-    maxlength = 0
-
-    for dir in filter(os.path.isdir,
-                      (os.path.join(pd, 'hgext') for pd in pathdirs())):
-        for e in os.listdir(dir):
-            if e.endswith('.py'):
-                name = e.rsplit('.', 1)[0]
-                path = os.path.join(dir, e)
-            else:
-                name = e
-                path = os.path.join(dir, e, '__init__.py')
-
-            if name in exts or name == '__init__' or not os.path.exists(path):
-                continue
-
-            try:
-                extensions.find(name)
-            except KeyError:
-                pass
-            else:
-                continue # enabled extension
-
-            try:
-                file = open(path)
-            except IOError:
-                continue
-            else:
-                doc = moduledoc(file)
-                file.close()
-
-            if doc: # extracting localized synopsis
-                exts[name] = gettext(doc).splitlines()[0]
-            else:
-                exts[name] = _('(no help text available)')
-            if len(name) > maxlength:
-                maxlength = len(name)
-
-    return exts, maxlength
-
-def enabledextensions():
-    '''Return the list of enabled extensions, and max name length'''
-    enabled = list(extensions.extensions())
-    exts = {}
-    maxlength = 0
-
-    if enabled:
-        exthelps = []
-        for ename, ext in enabled:
-            doc = (gettext(ext.__doc__) or _('(no help text available)'))
-            ename = ename.split('.')[-1]
-            maxlength = max(len(ename), maxlength)
-            exts[ename] = doc.splitlines(0)[0].strip()
-
-    return exts, maxlength
-
 def extensionslisting(header, exts, maxlength):
     '''Return a text listing of the given extensions'''
     result = ''
@@ -160,10 +85,10 @@ def topicextensions():
       hgext.baz = !
     ''')
 
-    exts, maxlength = enabledextensions()
+    exts, maxlength = extensions.enabled()
     doc += extensionslisting(_('enabled extensions:'), exts, maxlength)
 
-    exts, maxlength = additionalextensions()
+    exts, maxlength = extensions.disabled()
     doc += extensionslisting(_('non-enabled extensions:'), exts, maxlength)
 
     return doc