public void ParamExtractionWorks()
{
var ast = new MessageParser().Parse(@"{gender_of_host, select,
female {{
num_guests, plural, offset:1
=0 {{host} does not give a party.}
=1 {{host} invites {guest} to her party.}
=2 {{host} invites {guest} and one other person to her party.}
other {{host} invites {guest} and # other people to her party.}
}}
male {{
num_guests, plural, offset:1
=0 {{host} does not give a party.}
=1 {{host} invites {guest} to his party.}
=2 {{host} invites {guest} and one other person to his party.}
other {{host} invites {guest} and # other people to his party.}
}}
other {{
num_guests, plural, offset:1
=0 {{host} does not give a party.}
=1 {{host} invites {guest} to their party.}
=2 {{host} invites {guest} and one other person to their party.}
other {{host} invites {guest} and # other people to their party.}
}}
}");
var pars = new HashSet <string>();
ast.GatherParams(pars);
Assert.Equal(new List <string> {
"gender_of_host", "guest", "host", "num_guests"
}, pars.OrderBy(s => s));
}