Lucene.Net.Search.TestBoolean2.RandBoolQuery C# (CSharp) Method

        public static BooleanQuery RandBoolQuery(Random rnd, bool allowMust, int level, string field, string[] vals, Callback cb)
        {
            BooleanQuery current = new BooleanQuery(rnd.Next() < 0);
            for (int i = 0; i < rnd.Next(vals.Length) + 1; i++)
            {
                int qType = 0; // term query
                if (level > 0)
                {
                    qType = rnd.Next(10);
                }
                Query q;
                if (qType < 3)
                {
                    q = new TermQuery(new Term(field, vals[rnd.Next(vals.Length)]));
                }
                else if (qType < 4)
                {
                    Term t1 = new Term(field, vals[rnd.Next(vals.Length)]);
                    Term t2 = new Term(field, vals[rnd.Next(vals.Length)]);
                    PhraseQuery pq = new PhraseQuery();
                    pq.Add(t1);
                    pq.Add(t2);
                    pq.Slop = 10; // increase possibility of matching
                    q = pq;
                }
                else if (qType < 7)
                {
                    q = new WildcardQuery(new Term(field, "w*"));
                }
                else
                {
                    q = RandBoolQuery(rnd, allowMust, level - 1, field, vals, cb);
                }

                int r = rnd.Next(10);
                BooleanClause.Occur occur;
                if (r < 2)
                {
                    occur = BooleanClause.Occur.MUST_NOT;
                }
                else if (r < 5)
                {
                    if (allowMust)
                    {
                        occur = BooleanClause.Occur.MUST;
                    }
                    else
                    {
                        occur = BooleanClause.Occur.SHOULD;
                    }
                }
                else
                {
                    occur = BooleanClause.Occur.SHOULD;
                }

                current.Add(q, occur);
            }
            if (cb != null)
            {
                cb.PostCreate(current);
            }
            return current;
        }
    }

        public virtual void TestRandomQueries()
        {
            const string field = "data";

            string[] vals   = new string[] { "1", "2", "3", "4", "5", "6", "A", "Z", "B", "Y", "Z", "X", "foo" };
            int      maxLev = 4;

            // callback object to set a random setMinimumNumberShouldMatch
            TestBoolean2.Callback minNrCB = new CallbackAnonymousInnerClassHelper(this, field, vals);

            // increase number of iterations for more complete testing
            int num = AtLeast(20);

            for (int i = 0; i < num; i++)
            {
                int          lev  = Random.Next(maxLev);
                int          seed = Random.Next();
                BooleanQuery q1   = TestBoolean2.RandBoolQuery(new Random(seed), true, lev, field, vals, null);
                // BooleanQuery q2 = TestBoolean2.randBoolQuery(new Random(seed), lev, field, vals, minNrCB);
                BooleanQuery q2 = TestBoolean2.RandBoolQuery(new Random(seed), true, lev, field, vals, null);
                // only set minimumNumberShouldMatch on the top level query since setting
                // at a lower level can change the score.
                minNrCB.PostCreate(q2);

                // Can't use Hits because normalized scores will mess things
                // up.  The non-sorting version of search() that returns TopDocs
                // will not normalize scores.
                TopDocs top1 = s.Search(q1, null, 100);
                TopDocs top2 = s.Search(q2, null, 100);
                if (i < 100)
                {
                    QueryUtils.Check(
#if FEATURE_INSTANCE_TESTDATA_INITIALIZATION
                        this,
#endif
                        Random, q1, s);
                    QueryUtils.Check(
#if FEATURE_INSTANCE_TESTDATA_INITIALIZATION
                        this,
#endif
                        Random, q2, s);
                }
                AssertSubsetOfSameScores(q2, top1, top2);
            }
            // System.out.println("Total hits:"+tot);
        }