add tests for OnGetValue override

csharp/src/Client/AdbcDataReader.cs

@@ -54,7 +54,7 @@ public sealed class AdbcDataReader : DbDataReader, IDbColumnSchemaGenerator
         private int recordsAffected = -1;
 
         /// <summary>
-        /// An event that is raised when a value is read from an Arrow array.
+        /// An event that is raised when a value is read from an IArrowArray.
         /// </summary>
         /// <remarks>
         /// Callers may opt to provide overrides for parsing values.
@@ -86,7 +86,7 @@ internal AdbcDataReader(AdbcCommand adbcCommand, QueryResult adbcQueryResult, De
 
         public override object this[int ordinal] => GetValue(ordinal);
 
-        public override object this[string name] => GetValue(this.RecordBatch.Column(name), GetOrdinal(name)) ?? DBNull.Value;
+        public override object this[string name] => GetValue(this.RecordBatch.Column(name)) ?? DBNull.Value;
 
         public override int Depth => 0;
 
@@ -247,7 +247,7 @@ public override string GetString(int ordinal)
 
         public override object GetValue(int ordinal)
         {
-            object? value = GetValue(this.RecordBatch.Column(ordinal), ordinal);
+            object? value = GetValue(this.RecordBatch.Column(ordinal));
 
             if (value == null)
                 return DBNull.Value;
@@ -362,10 +362,10 @@ public ReadOnlyCollection<AdbcColumn> GetAdbcColumnSchema()
         /// </summary>
         /// <param name="arrowArray"></param>
         /// <returns></returns>
-        public object? GetValue(IArrowArray arrowArray, int ordinal)
+        private object? GetValue(IArrowArray arrowArray)
         {
             // if the OnGetValue event is set, call it
-            object? result = OnGetValue?.Invoke(arrowArray, ordinal);
+            object? result = OnGetValue?.Invoke(arrowArray, this.currentRowInRecordBatch);
 
             // if the value is null, try to get the value from the ArrowArray
             result = result ?? arrowArray.ValueAt(this.currentRowInRecordBatch);

csharp/test/Apache.Arrow.Adbc.Tests/Client/ClientTests.cs

@@ -18,6 +18,7 @@
 using System;
 using System.Collections.Generic;
 using System.Data.SqlTypes;
+using System.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Apache.Arrow.Adbc.Client;
@@ -43,6 +44,56 @@ public void TestDecimalValues(DecimalBehavior decimalBehavior, string value, int
             Assert.True(rdrValue.GetType().Equals(expectedType));
         }
 
+        /// <summary>
+        /// Demonstrates the OnGetValue method of an AdbcDataReader.
+        /// </summary>
+        /// <param name="treatIntegersAsStrings">True/False to treat integers as strings.</param>
+        [Theory]
+        [InlineData(true)]
+        [InlineData(false)]
+        public void TestOnGetValue(bool treatIntegersAsStrings)
+        {
+            AdbcDataReader rdr = GetMoqDataReaderForIntegers();
+
+            if (treatIntegersAsStrings)
+            {
+                rdr.OnGetValue += (o, e) =>
+                {
+                    if (o != null)
+                    {
+                        Int32Array? ints = o as Int32Array;
+
+                        if (ints != null)
+                        {
+                            int? value = ints.GetValue(e);
+
+                            if (value.HasValue)
+                                return value.Value.ToString();
+                            else
+                                return string.Empty;
+                        }
+                    }
+
+                    return string.Empty;
+                };
+            }
+
+            while (rdr.Read())
+            {
+                object? rdrValue = rdr.GetValue(0);
+
+                if (treatIntegersAsStrings)
+                {
+                    Assert.True(rdrValue.GetType().Equals(typeof(string)));
+                }
+                else
+                {
+                    if (rdrValue != DBNull.Value)
+                        Assert.True(rdrValue.GetType().Equals(typeof(int)));
+                }
+            }
+        }
+
         private AdbcDataReader GetMoqDataReader(DecimalBehavior decimalBehavior, string value, int precision, int scale)
         {
             SqlDecimal sqlDecimal = SqlDecimal.Parse(value);
@@ -80,6 +131,41 @@ private AdbcDataReader GetMoqDataReader(DecimalBehavior decimalBehavior, string
             AdbcDataReader reader = cmd.ExecuteReader();
             return reader;
         }
+
+        private AdbcDataReader GetMoqDataReaderForIntegers()
+        {
+            List<KeyValuePair<string, string>> metadata = new List<KeyValuePair<string, string>>();
+            List<Field> fields = new List<Field>();
+            fields.Add(new Field("TestIntegers", new Int32Type(), true, metadata));
+
+            Schema schema = new Schema(fields, metadata);
+            Int32Array.Builder numbersBuilder = new Int32Array.Builder();
+            numbersBuilder.AppendRange(new List<int>() { 1, 2, 3 });
+            numbersBuilder.AppendNull(); //null for #4
+            numbersBuilder.Append(5);
+
+            Int32Array numbersArray = numbersBuilder.Build();
+
+            List<IArrowArray> values = new List<IArrowArray>() { numbersArray };
+
+            List<RecordBatch> records = new List<RecordBatch>()
+            {
+                new RecordBatch(schema, values, numbersArray.Count())
+            };
+
+            MockArrayStream mockArrayStream = new MockArrayStream(schema, records);
+            QueryResult queryResult = new QueryResult(1, mockArrayStream);
+
+            Mock<AdbcStatement> mockStatement = new Mock<AdbcStatement>();
+            mockStatement.Setup(x => x.ExecuteQuery()).Returns(queryResult); ;
+
+            Adbc.Client.AdbcConnection mockConnection = new Adbc.Client.AdbcConnection();
+
+            AdbcCommand cmd = new AdbcCommand(mockStatement.Object, mockConnection);
+
+            AdbcDataReader reader = cmd.ExecuteReader();
+            return reader;
+        }
     }
 
     class MockArrayStream : IArrowArrayStream