# HG changeset patch
# User Augie Fackler <augie@google.com>
# Date 1539506245 14400
# Node ID 96164fb9b9130bc2148fc454cf4c6eed0797c001
# Parent  46b55f279571b31f5869062db73fa8105b675683
logcmdutil: add a helpful assertion to catch mistyped templates early

This would have made a defect in test-notify.t much easier to figure out.

Differential Revision: https://phab.mercurial-scm.org/D5097

diff -r 46b55f279571 -r 96164fb9b913 mercurial/logcmdutil.py
--- a/mercurial/logcmdutil.py	Sun Oct 14 05:28:01 2018 -0400
+++ b/mercurial/logcmdutil.py	Sun Oct 14 04:37:25 2018 -0400
@@ -460,6 +460,8 @@
                 self.footer = self.t.render(self._parts['footer'], props)
 
 def templatespec(tmpl, mapfile):
+    if pycompat.ispy3:
+        assert not isinstance(tmpl, str), 'tmpl must not be a str'
     if mapfile:
         return formatter.templatespec('changeset', tmpl, mapfile)
     else: