templater: drop \ when handling escaped {

mercurial/templater.py

@@ -121,7 +121,7 b' class engine(object):'
                 break
             if n > 0 and tmpl[n - 1] == '\\':
                 # escaped
-                parsed.append((None, tmpl[pos:n + 1]))
+                parsed.append((None, tmpl[pos:n - 1] + "{"))
                 pos = n + 1
                 continue
             if n > pos: