diff --git a/contrib/python3-whitelist b/contrib/python3-whitelist
--- a/contrib/python3-whitelist
+++ b/contrib/python3-whitelist
@@ -261,6 +261,7 @@
 test-hgk.t
 test-hgrc.t
 test-hgweb-annotate-whitespace.t
+test-hgweb-auth.py
 test-hgweb-bundle.t
 test-hgweb-commands.t
 test-hgweb-csp.t
diff --git a/tests/test-hgweb-auth.py b/tests/test-hgweb-auth.py
--- a/tests/test-hgweb-auth.py
+++ b/tests/test-hgweb-auth.py
@@ -24,16 +24,26 @@
 def writeauth(items):
     ui = origui.copy()
     for name, value in items.items():
-        ui.setconfig('auth', name, value)
+        ui.setconfig(b'auth', name, value)
     return ui
 
+def _stringifyauthinfo(ai):
+    if ai is None:
+        return ai
+    realm, authuris, user, passwd = ai
+    return (pycompat.strurl(realm),
+            [pycompat.strurl(u) for u in authuris],
+            pycompat.strurl(user),
+            pycompat.strurl(passwd),
+    )
+
 def test(auth, urls=None):
     print('CFG:', pycompat.sysstr(stringutil.pprint(auth, bprefix=True)))
     prefixes = set()
     for k in auth:
-        prefixes.add(k.split('.', 1)[0])
+        prefixes.add(k.split(b'.', 1)[0])
     for p in prefixes:
-        for name in ('.username', '.password'):
+        for name in (b'.username', b'.password'):
             if (p + name) not in auth:
                 auth[p + name] = p
     auth = dict((k, v) for k, v in auth.items() if v is not None)
@@ -41,106 +51,109 @@
     ui = writeauth(auth)
 
     def _test(uri):
-        print('URI:', uri)
+        print('URI:', pycompat.strurl(uri))
         try:
             pm = url.passwordmgr(ui, urlreq.httppasswordmgrwithdefaultrealm())
             u, authinfo = util.url(uri).authinfo()
             if authinfo is not None:
-                pm.add_password(*authinfo)
-            print('    ', pm.find_user_password('test', u))
+                pm.add_password(*_stringifyauthinfo(authinfo))
+            print('    ', tuple(pycompat.strurl(a) for a in
+                                pm.find_user_password('test',
+                                                      pycompat.strurl(u))))
         except error.Abort:
             print('    ','abort')
 
     if not urls:
         urls = [
-            'http://example.org/foo',
-            'http://example.org/foo/bar',
-            'http://example.org/bar',
-            'https://example.org/foo',
-            'https://example.org/foo/bar',
-            'https://example.org/bar',
-            'https://x@example.org/bar',
-            'https://y@example.org/bar',
+            b'http://example.org/foo',
+            b'http://example.org/foo/bar',
+            b'http://example.org/bar',
+            b'https://example.org/foo',
+            b'https://example.org/foo/bar',
+            b'https://example.org/bar',
+            b'https://x@example.org/bar',
+            b'https://y@example.org/bar',
             ]
     for u in urls:
         _test(u)
 
 
 print('\n*** Test in-uri schemes\n')
-test({'x.prefix': 'http://example.org'})
-test({'x.prefix': 'https://example.org'})
-test({'x.prefix': 'http://example.org', 'x.schemes': 'https'})
-test({'x.prefix': 'https://example.org', 'x.schemes': 'http'})
+test({b'x.prefix': b'http://example.org'})
+test({b'x.prefix': b'https://example.org'})
+test({b'x.prefix': b'http://example.org', b'x.schemes': b'https'})
+test({b'x.prefix': b'https://example.org', b'x.schemes': b'http'})
 
 print('\n*** Test separately configured schemes\n')
-test({'x.prefix': 'example.org', 'x.schemes': 'http'})
-test({'x.prefix': 'example.org', 'x.schemes': 'https'})
-test({'x.prefix': 'example.org', 'x.schemes': 'http https'})
+test({b'x.prefix': b'example.org', b'x.schemes': b'http'})
+test({b'x.prefix': b'example.org', b'x.schemes': b'https'})
+test({b'x.prefix': b'example.org', b'x.schemes': b'http https'})
 
 print('\n*** Test prefix matching\n')
-test({'x.prefix': 'http://example.org/foo',
-      'y.prefix': 'http://example.org/bar'})
-test({'x.prefix': 'http://example.org/foo',
-      'y.prefix': 'http://example.org/foo/bar'})
-test({'x.prefix': '*', 'y.prefix': 'https://example.org/bar'})
+test({b'x.prefix': b'http://example.org/foo',
+      b'y.prefix': b'http://example.org/bar'})
+test({b'x.prefix': b'http://example.org/foo',
+      b'y.prefix': b'http://example.org/foo/bar'})
+test({b'x.prefix': b'*', b'y.prefix': b'https://example.org/bar'})
 
 print('\n*** Test user matching\n')
-test({'x.prefix': 'http://example.org/foo',
-      'x.username': None,
-      'x.password': 'xpassword'},
-     urls=['http://y@example.org/foo'])
-test({'x.prefix': 'http://example.org/foo',
-      'x.username': None,
-      'x.password': 'xpassword',
-      'y.prefix': 'http://example.org/foo',
-      'y.username': 'y',
-      'y.password': 'ypassword'},
-     urls=['http://y@example.org/foo'])
-test({'x.prefix': 'http://example.org/foo/bar',
-      'x.username': None,
-      'x.password': 'xpassword',
-      'y.prefix': 'http://example.org/foo',
-      'y.username': 'y',
-      'y.password': 'ypassword'},
-     urls=['http://y@example.org/foo/bar'])
+test({b'x.prefix': b'http://example.org/foo',
+      b'x.username': None,
+      b'x.password': b'xpassword'},
+     urls=[b'http://y@example.org/foo'])
+test({b'x.prefix': b'http://example.org/foo',
+      b'x.username': None,
+      b'x.password': b'xpassword',
+      b'y.prefix': b'http://example.org/foo',
+      b'y.username': b'y',
+      b'y.password': b'ypassword'},
+     urls=[b'http://y@example.org/foo'])
+test({b'x.prefix': b'http://example.org/foo/bar',
+      b'x.username': None,
+      b'x.password': b'xpassword',
+      b'y.prefix': b'http://example.org/foo',
+      b'y.username': b'y',
+      b'y.password': b'ypassword'},
+     urls=[b'http://y@example.org/foo/bar'])
 
 print('\n*** Test user matching with name in prefix\n')
 
 # prefix, username and URL have the same user
-test({'x.prefix': 'https://example.org/foo',
-      'x.username': None,
-      'x.password': 'xpassword',
-      'y.prefix': 'http://y@example.org/foo',
-      'y.username': 'y',
-      'y.password': 'ypassword'},
-     urls=['http://y@example.org/foo'])
+test({b'x.prefix': b'https://example.org/foo',
+      b'x.username': None,
+      b'x.password': b'xpassword',
+      b'y.prefix': b'http://y@example.org/foo',
+      b'y.username': b'y',
+      b'y.password': b'ypassword'},
+     urls=[b'http://y@example.org/foo'])
 # Prefix has a different user from username and URL
-test({'y.prefix': 'http://z@example.org/foo',
-      'y.username': 'y',
-      'y.password': 'ypassword'},
-     urls=['http://y@example.org/foo'])
+test({b'y.prefix': b'http://z@example.org/foo',
+      b'y.username': b'y',
+      b'y.password': b'ypassword'},
+     urls=[b'http://y@example.org/foo'])
 # Prefix has a different user from URL; no username
-test({'y.prefix': 'http://z@example.org/foo',
-      'y.password': 'ypassword'},
-     urls=['http://y@example.org/foo'])
+test({b'y.prefix': b'http://z@example.org/foo',
+      b'y.password': b'ypassword'},
+     urls=[b'http://y@example.org/foo'])
 # Prefix and URL have same user, but doesn't match username
-test({'y.prefix': 'http://y@example.org/foo',
-      'y.username': 'z',
-      'y.password': 'ypassword'},
-     urls=['http://y@example.org/foo'])
+test({b'y.prefix': b'http://y@example.org/foo',
+      b'y.username': b'z',
+      b'y.password': b'ypassword'},
+     urls=[b'http://y@example.org/foo'])
 # Prefix and URL have the same user; no username
-test({'y.prefix': 'http://y@example.org/foo',
-      'y.password': 'ypassword'},
-     urls=['http://y@example.org/foo'])
+test({b'y.prefix': b'http://y@example.org/foo',
+      b'y.password': b'ypassword'},
+     urls=[b'http://y@example.org/foo'])
 # Prefix user, but no URL user or username
-test({'y.prefix': 'http://y@example.org/foo',
-      'y.password': 'ypassword'},
-     urls=['http://example.org/foo'])
+test({b'y.prefix': b'http://y@example.org/foo',
+      b'y.password': b'ypassword'},
+     urls=[b'http://example.org/foo'])
 
 def testauthinfo(fullurl, authurl):
     print('URIs:', fullurl, authurl)
     pm = urlreq.httppasswordmgrwithdefaultrealm()
-    pm.add_password(*util.url(fullurl).authinfo()[1])
+    ai = _stringifyauthinfo(util.url(pycompat.bytesurl(fullurl)).authinfo()[1])
+    pm.add_password(*ai)
     print(pm.find_user_password('test', authurl))
 
 print('\n*** Test urllib2 and util.url\n')