@Test
    void testSimplePositive() {
        PhraseItem root = new PhraseItem();
        root.addItem(new WordItem("abc"));
        assertEquals("abc", transformQuery(root));
    }
Check CollapsePhraseSearcher works and only is triggered when it
should.

@author Steinar Knutsen
container-search/src/test/java/com/yahoo/prelude/querytransform/test/CollapsePhraseSearcherTestCase.java