diff --git a/hgext/churn.py b/hgext/churn.py
--- a/hgext/churn.py
+++ b/hgext/churn.py
@@ -135,7 +135,7 @@ def churn(ui, repo, *pats, **opts):
             except ValueError:
                 l = l.strip()
                 if l:
-                    ui.warn(_("skipping malformed alias: %s\n" % l))
+                    ui.warn(_("skipping malformed alias: %s\n") % l)
                 continue
 
     rate = countrate(ui, repo, amap, *pats, **opts).items()
diff --git a/hgext/convert/monotone.py b/hgext/convert/monotone.py
--- a/hgext/convert/monotone.py
+++ b/hgext/convert/monotone.py
@@ -113,7 +113,7 @@ class monotone_source(converter_source, 
 
         stream = self.mtnreadfp.read(1)
         if stream not in 'mewptl':
-            raise util.Abort(_('bad mtn packet - bad stream type %s' % stream))
+            raise util.Abort(_('bad mtn packet - bad stream type %s') % stream)
 
         read = self.mtnreadfp.read(1)
         if read != ':':
diff --git a/hgext/largefiles/lfcommands.py b/hgext/largefiles/lfcommands.py
--- a/hgext/largefiles/lfcommands.py
+++ b/hgext/largefiles/lfcommands.py
@@ -309,7 +309,7 @@ def _converttags(ui, revmap, data):
             newdata.append('%s %s\n' % (node.hex(revmap[newid]),
                 name))
         except KeyError:
-            ui.warn(_('no mapping for id %s\n' % id))
+            ui.warn(_('no mapping for id %s\n') % id)
             continue
     return ''.join(newdata)
 
diff --git a/hgext/largefiles/overrides.py b/hgext/largefiles/overrides.py
--- a/hgext/largefiles/overrides.py
+++ b/hgext/largefiles/overrides.py
@@ -157,7 +157,7 @@ def remove_largefiles(ui, repo, *pats, *
                 # If this is being called by addremove, notify the user that we
                 # are removing the file.
                 if getattr(repo, "_isaddremove", False):
-                    ui.status(_('removing %s\n' % f))
+                    ui.status(_('removing %s\n') % f)
                 if os.path.exists(repo.wjoin(f)):
                     util.unlinkpath(repo.wjoin(f))
             lfdirstate.remove(f)
@@ -682,7 +682,7 @@ def override_pull(orig, ui, repo, source
         for head in newheads:
             (cached, missing) = lfcommands.cachelfiles(ui, repo, head)
             numcached += len(cached)
-        ui.status(_("%d largefiles cached\n" % numcached))
+        ui.status(_("%d largefiles cached\n") % numcached)
     return result
 
 def override_rebase(orig, ui, repo, **opts):
diff --git a/hgext/mq.py b/hgext/mq.py
--- a/hgext/mq.py
+++ b/hgext/mq.py
@@ -1193,7 +1193,8 @@ class queue(object):
                 root = self.series[start]
                 target = patchheader(self.join(root), self.plainmode).parent
                 if not target:
-                    raise util.Abort(_("%s does not have a parent recorded" % root))
+                    raise util.Abort(
+                        _("%s does not have a parent recorded") % root)
                 if not repo[target] == repo['.']:
                     hg.update(repo, target)
 
diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -2908,7 +2908,7 @@ def heads(ui, repo, *branchrevs, **opts)
             headless = ', '.join(b for b in branches - haveheads)
             msg = _('no open branch heads found on branches %s')
             if opts.get('rev'):
-                msg += _(' (started at %s)' % opts['rev'])
+                msg += _(' (started at %s)') % opts['rev']
             ui.warn((msg + '\n') % headless)
 
     if not heads:
@@ -3001,7 +3001,7 @@ def help_(ui, name=None, unknowncmd=Fals
                 msg = _('use "hg help" for the full list of commands '
                         'or "hg -v" for details')
             elif name and not full:
-                msg = _('use "hg help %s" to show the full help text' % name)
+                msg = _('use "hg help %s" to show the full help text') % name
             elif aliases:
                 msg = _('use "hg -v help%s" to show builtin aliases and '
                         'global options') % (name and " " + name or "")
@@ -4284,7 +4284,7 @@ def postincoming(ui, repo, modheads, opt
         try:
             ret = hg.update(repo, checkout)
         except util.Abort, inst:
-            ui.warn(_("not updating: %s\n" % str(inst)))
+            ui.warn(_("not updating: %s\n") % str(inst))
             return 0
         if not ret and not checkout:
             if bookmarks.update(repo, [movemarkfrom], repo['.'].node()):
diff --git a/tests/test-check-code-hg.t b/tests/test-check-code-hg.t
--- a/tests/test-check-code-hg.t
+++ b/tests/test-check-code-hg.t
@@ -209,9 +209,6 @@
    >                             if os.path.exists(self.wjoin(lfutil.standin(lfile))):
    warning: line over 80 characters
   hgext/mq.py:0:
-   >                     raise util.Abort(_("%s does not have a parent recorded" % root))
-   warning: line over 80 characters
-  hgext/mq.py:0:
    >                     raise util.Abort(_("cannot push --exact with applied patches"))
    warning: line over 80 characters
   hgext/mq.py:0: