--- a/mercurial/templatefuncs.py	Sun Apr 29 14:29:09 2018 -0700
+++ b/mercurial/templatefuncs.py	Mon May 07 09:15:29 2018 -0700
@@ -12,6 +12,7 @@
 from .i18n import _
 from .node import (
     bin,
+    wdirid,
 )
 from . import (
     color,
@@ -601,7 +602,9 @@
     else:
         try:
             node = scmutil.resolvehexnodeidprefix(repo, hexnode)
-        except (error.LookupError, error.WdirUnsupported):
+        except error.WdirUnsupported:
+            node = wdirid
+        except error.LookupError:
             return hexnode
         if not node:
             return hexnode