@ParameterizedTest
    @ValueSource(strings = {"Hello", "HeLlo", "HELLO"})
    public void testWithUpperCaseWord(String wordWithUpperCase) {
        var result = searchWord(
                wordWithUpperCase,
                Optional.of(Language.ENGLISH),
                Optional.empty(),
                Optional.empty(),
                Optional.empty()
        );
        var resultWord = getFirstWord(result);

        var lowerCaseWord = "hello";
        var documentFrequency = getModelDocumentFrequencyWithEnglish(lowerCaseWord);

        assertEquals(documentFrequency, resultWord.getDocumentFrequency());
    }
Tests significance term in the search chain.

@author MariusArhaug
container-search/src/test/java/com/yahoo/search/significance/test/SignificanceSearcherTest.java