public void TestSignaturesV2_3_X()
        {
            DataFrameReader dfr = _spark.Read();

            Assert.IsType <DataFrameReader>(dfr.Format("json"));

            Assert.IsType <DataFrameReader>(
                dfr.Schema(
                    new StructType(new[]
            {
                new StructField("age", new IntegerType()),
                new StructField("name", new StringType())
            })));
            Assert.IsType <DataFrameReader>(dfr.Schema("age INT, name STRING"));

            Assert.IsType <DataFrameReader>(dfr.Option("stringOption", "value"));
            Assert.IsType <DataFrameReader>(dfr.Option("boolOption", true));
            Assert.IsType <DataFrameReader>(dfr.Option("longOption", 1L));
            Assert.IsType <DataFrameReader>(dfr.Option("doubleOption", 3D));

            Assert.IsType <DataFrameReader>(
                dfr.Options(
                    new Dictionary <string, string>
            {
                { "option1", "value1" },
                { "option2", "value2" }
            }));

            string jsonFile = $"{TestEnvironment.ResourceDirectory}people.json";

            Assert.IsType <DataFrame>(dfr.Load());
            Assert.IsType <DataFrame>(dfr.Load(jsonFile));
            Assert.IsType <DataFrame>(dfr.Load(jsonFile, jsonFile));

            Assert.IsType <DataFrame>(dfr.Json(jsonFile));
            Assert.IsType <DataFrame>(dfr.Json(jsonFile, jsonFile));

            string csvFile = $"{TestEnvironment.ResourceDirectory}people.csv";

            Assert.IsType <DataFrame>(dfr.Csv(csvFile));
            Assert.IsType <DataFrame>(dfr.Csv(csvFile, csvFile));

            string parquetFile = $"{TestEnvironment.ResourceDirectory}users.parquet";

            Assert.IsType <DataFrame>(dfr.Parquet(parquetFile));
            Assert.IsType <DataFrame>(dfr.Parquet(parquetFile, parquetFile));

            string orcFile = $"{TestEnvironment.ResourceDirectory}users.orc";

            Assert.IsType <DataFrame>(dfr.Orc(orcFile));
            Assert.IsType <DataFrame>(dfr.Orc(orcFile, orcFile));

            dfr = _spark.Read();
            string textFile = $"{TestEnvironment.ResourceDirectory}people.txt";

            Assert.IsType <DataFrame>(dfr.Text(textFile));
            Assert.IsType <DataFrame>(dfr.Text(textFile, textFile));
        }
        public void TestParquet()
        {
            // arrange
            mockDataFrameReaderProxy.Setup(m => m.Parquet(It.IsAny <string[]>()));
            var dataFrameReader = new DataFrameReader(mockDataFrameReaderProxy.Object, sparkContext);

            // act
            const string path1  = "path/to/json";
            const string path2  = "path/to/json";
            var          reader = dataFrameReader.Parquet(path1, path2);

            // Assert
            Assert.IsNotNull(reader);
            mockDataFrameReaderProxy.Verify(m => m.Parquet(
                                                It.Is <string[]>(strArray => strArray.Length == 2 && strArray[0] == path1 && strArray[1] == path2)), Times.Once);
        }