final FunctionIdent ident = new FunctionIdent(CollectionAverageFunction.NAME,
ImmutableList.<DataType>of(new SetType(DataTypes.LONG)));
@Test
public void testLookup() throws Exception {
Injector injector = new ModulesBuilder().add(
new ScalarFunctionModule()
).createInjector();
Functions functions = injector.getInstance(Functions.class);