@Test
    public void testArgument() {
        assertFalse(FeatureNames.argumentOf("foo(bar)").isPresent());
        assertFalse(FeatureNames.argumentOf("foo(bar.baz)").isPresent());
        assertEquals("bar", FeatureNames.argumentOf("query(bar)").get());
        assertEquals("bar.baz", FeatureNames.argumentOf("query(bar.baz)").get());
        assertEquals("bar", FeatureNames.argumentOf("attribute(bar)").get());
        assertEquals("bar.baz", FeatureNames.argumentOf("attribute(bar.baz)").get());
        assertEquals("bar", FeatureNames.argumentOf("constant(bar)").get());
        assertEquals("bar.baz", FeatureNames.argumentOf("constant(bar.baz)").get());
    }
Tests rank feature names.

@author bratseth
searchlib/src/test/java/com/yahoo/searchlib/ranking/features/FeatureNamesTestCase.java