diff --git a/mercurial/debugcommands.py b/mercurial/debugcommands.py
--- a/mercurial/debugcommands.py
+++ b/mercurial/debugcommands.py
@@ -560,7 +560,7 @@
         d = util.parsedate(date, util.extendeddateformats)
     else:
         d = util.parsedate(date)
-    ui.write(("internal: %s %s\n") % d)
+    ui.write(("internal: %d %d\n") % d)
     ui.write(("standard: %s\n") % util.datestr(d))
     if range:
         m = util.matchdate(range)
diff --git a/mercurial/tags.py b/mercurial/tags.py
--- a/mercurial/tags.py
+++ b/mercurial/tags.py
@@ -276,7 +276,7 @@
     count = 0
 
     def dbg(msg):
-        ui.debug("%s, line %s: %s\n" % (fn, count, msg))
+        ui.debug("%s, line %d: %s\n" % (fn, count, msg))
 
     for nline, line in enumerate(lines):
         count += 1