templater: drop redundant type conversion when evaluating integer argument

A function argument may be an integer. In this case, it isn't necessary to
convert a value to string and back to integer.

Because an argument may be an arbitrary object (e.g. date tuple), TypeError
should be caught as well.

mercurial/templater.py

@@ -221,9 +221,10 b' def evalfuncarg(context, mapping, arg):'
     return thing
 
 def evalinteger(context, mapping, arg, err):
+    v = evalfuncarg(context, mapping, arg)
     try:
-        return int(stringify(arg[0](context, mapping, arg[1])))
-    except ValueError:
+        return int(v)
+    except (TypeError, ValueError):
         raise error.ParseError(err)
 
 def runinteger(context, mapping, data):

tests/test-command-template.t

@@ -3148,6 +3148,9 b' Test recursive evaluation:'
   text.1:be wrapped
   text.1:desc to be
   text.1:wrapped (no-eol)
+  $ hg log -l1 -T '{fill(desc, date, "", "")}\n'
+  hg: parse error: fill expects an integer width
+  [255]
 
   $ hg log -l 1 --template '{sub(r"[0-9]", "-", author)}'
   {node|short} (no-eol)