public void testSetAllGroups() throws Exception {
    Directory dir = newDirectory();
    RandomIndexWriter w =
        new RandomIndexWriter(
            random(),
            dir,
            newIndexWriterConfig(new MockAnalyzer(random())).setMergePolicy(newLogMergePolicy()));
    Document doc = new Document();
    doc.add(newField("group", "foo", StringField.TYPE_NOT_STORED));
    doc.add(new SortedDocValuesField("group", new BytesRef("foo")));
    w.addDocument(doc);

    IndexSearcher indexSearcher = newSearcher(w.getReader());
    w.close();

    GroupingSearch gs = new GroupingSearch("group");
    gs.setAllGroups(true);
    TopGroups<?> groups = gs.search(indexSearcher, new TermQuery(new Term("group", "foo")), 0, 10);
    assertEquals(1, groups.totalHitCount);
    // assertEquals(1, groups.totalGroupCount.intValue());
    assertEquals(1, groups.totalGroupedHitCount);
    assertEquals(1, gs.getAllMatchingGroups().size());
    indexSearcher.getIndexReader().close();
    dir.close();
  }
  private GroupingSearch createRandomGroupingSearch(
      String groupField, Sort groupSort, int docsInGroup, boolean canUseIDV) {
    GroupingSearch groupingSearch;
    if (random().nextBoolean()) {
      ValueSource vs = new BytesRefFieldSource(groupField);
      groupingSearch = new GroupingSearch(vs, new HashMap<>());
    } else {
      groupingSearch = new GroupingSearch(groupField);
    }

    groupingSearch.setGroupSort(groupSort);
    groupingSearch.setGroupDocsLimit(docsInGroup);

    if (random().nextBoolean()) {
      groupingSearch.setCachingInMB(4.0, true);
    }

    return groupingSearch;
  }
  // Tests some very basic usages...
  public void testBasic() throws Exception {

    final String groupField = "author";

    FieldType customType = new FieldType();
    customType.setStored(true);

    Directory dir = newDirectory();
    RandomIndexWriter w =
        new RandomIndexWriter(
            random(),
            dir,
            newIndexWriterConfig(new MockAnalyzer(random())).setMergePolicy(newLogMergePolicy()));
    boolean canUseIDV = true;
    List<Document> documents = new ArrayList<>();
    // 0
    Document doc = new Document();
    addGroupField(doc, groupField, "author1", canUseIDV);
    doc.add(new TextField("content", "random text", Field.Store.YES));
    doc.add(new Field("id", "1", customType));
    documents.add(doc);

    // 1
    doc = new Document();
    addGroupField(doc, groupField, "author1", canUseIDV);
    doc.add(new TextField("content", "some more random text", Field.Store.YES));
    doc.add(new Field("id", "2", customType));
    documents.add(doc);

    // 2
    doc = new Document();
    addGroupField(doc, groupField, "author1", canUseIDV);
    doc.add(new TextField("content", "some more random textual data", Field.Store.YES));
    doc.add(new Field("id", "3", customType));
    doc.add(new StringField("groupend", "x", Field.Store.NO));
    documents.add(doc);
    w.addDocuments(documents);
    documents.clear();

    // 3
    doc = new Document();
    addGroupField(doc, groupField, "author2", canUseIDV);
    doc.add(new TextField("content", "some random text", Field.Store.YES));
    doc.add(new Field("id", "4", customType));
    doc.add(new StringField("groupend", "x", Field.Store.NO));
    w.addDocument(doc);

    // 4
    doc = new Document();
    addGroupField(doc, groupField, "author3", canUseIDV);
    doc.add(new TextField("content", "some more random text", Field.Store.YES));
    doc.add(new Field("id", "5", customType));
    documents.add(doc);

    // 5
    doc = new Document();
    addGroupField(doc, groupField, "author3", canUseIDV);
    doc.add(new TextField("content", "random", Field.Store.YES));
    doc.add(new Field("id", "6", customType));
    doc.add(new StringField("groupend", "x", Field.Store.NO));
    documents.add(doc);
    w.addDocuments(documents);
    documents.clear();

    // 6 -- no author field
    doc = new Document();
    doc.add(new TextField("content", "random word stuck in alot of other text", Field.Store.YES));
    doc.add(new Field("id", "6", customType));
    doc.add(new StringField("groupend", "x", Field.Store.NO));

    w.addDocument(doc);

    IndexSearcher indexSearcher = newSearcher(w.getReader());
    w.close();

    Sort groupSort = Sort.RELEVANCE;
    GroupingSearch groupingSearch = createRandomGroupingSearch(groupField, groupSort, 5, canUseIDV);

    TopGroups<?> groups =
        groupingSearch.search(indexSearcher, new TermQuery(new Term("content", "random")), 0, 10);

    assertEquals(7, groups.totalHitCount);
    assertEquals(7, groups.totalGroupedHitCount);
    assertEquals(4, groups.groups.length);

    // relevance order: 5, 0, 3, 4, 1, 2, 6

    // the later a document is added the higher this docId
    // value
    GroupDocs<?> group = groups.groups[0];
    compareGroupValue("author3", group);
    assertEquals(2, group.scoreDocs.length);
    assertEquals(5, group.scoreDocs[0].doc);
    assertEquals(4, group.scoreDocs[1].doc);
    assertTrue(group.scoreDocs[0].score > group.scoreDocs[1].score);

    group = groups.groups[1];
    compareGroupValue("author1", group);
    assertEquals(3, group.scoreDocs.length);
    assertEquals(0, group.scoreDocs[0].doc);
    assertEquals(1, group.scoreDocs[1].doc);
    assertEquals(2, group.scoreDocs[2].doc);
    assertTrue(group.scoreDocs[0].score > group.scoreDocs[1].score);
    assertTrue(group.scoreDocs[1].score > group.scoreDocs[2].score);

    group = groups.groups[2];
    compareGroupValue("author2", group);
    assertEquals(1, group.scoreDocs.length);
    assertEquals(3, group.scoreDocs[0].doc);

    group = groups.groups[3];
    compareGroupValue(null, group);
    assertEquals(1, group.scoreDocs.length);
    assertEquals(6, group.scoreDocs[0].doc);

    Filter lastDocInBlock = new QueryWrapperFilter(new TermQuery(new Term("groupend", "x")));
    groupingSearch = new GroupingSearch(lastDocInBlock);
    groups =
        groupingSearch.search(indexSearcher, new TermQuery(new Term("content", "random")), 0, 10);

    assertEquals(7, groups.totalHitCount);
    assertEquals(7, groups.totalGroupedHitCount);
    assertEquals(4, groups.totalGroupCount.longValue());
    assertEquals(4, groups.groups.length);

    indexSearcher.getIndexReader().close();
    dir.close();
  }