templater: add no-op template function 'label'

mercurial/templater.py

@@ -265,6 +265,15 b' def ifeq(context, mapping, args):'
         t = stringify(args[3][0](context, mapping, args[3][1]))
         yield runtemplate(context, mapping, compiletemplate(t, context))
 
+def label(context, mapping, args):
+    if len(args) != 2:
+        # i18n: "label" is a keyword
+        raise error.ParseError(_("label expects two arguments"))
+
+    # ignore args[0] (the label string) since this is supposed to be a a no-op
+    t = stringify(args[1][0](context, mapping, args[1][1]))
+    yield runtemplate(context, mapping, compiletemplate(t, context))
+
 methods = {
     "string": lambda e, c: (runstring, e[1]),
     "symbol": lambda e, c: (runsymbol, e[1]),
@@ -280,6 +289,7 b' funcs = {'
     "ifeq": ifeq,
     "join": join,
     "sub": sub,
+    "label": label,
 }
 
 # template engine