feat: method DataTypeName returns the field type as defined in the source

PocketCsvReader.Testing/CsvRawRecordTest.cs

@@ -0,0 +1,25 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using NUnit.Framework;
+using PocketCsvReader.Configuration;
+
+namespace PocketCsvReader.Testing;
+public class CsvRawRecordTest
+{
+    [Test]
+    public void GetDataTypeName_WithIndexedSchema_CorrectNames()
+    {
+        var schema = new SchemaDescriptorBuilder()
+                            .Indexed()   
+                            .WithNumericField<decimal>((f) => f.WithDataSourceTypeName("number"))
+                            .WithField<string>((f) => f.WithDataSourceTypeName("string"))
+                            .Build();
+        var profile = new CsvProfile(new DialectDescriptor(), schema);
+        var rawRecord = new CsvRawRecord(profile);
+        Assert.That(rawRecord.GetDataTypeName(0), Is.EqualTo("number"));
+        Assert.That(rawRecord.GetDataTypeName(1), Is.EqualTo("string"));
+    }
+}

PocketCsvReader/Configuration/FieldDescriptor.cs

@@ -12,5 +12,6 @@ Type RuntimeType
     , string? Name = null
     , string? Format = null
     , ImmutableSequenceCollection? Sequences = null
+    , string DataSourceTypeName = ""
 )
 { }

PocketCsvReader/Configuration/FieldDescriptorBuilder.cs

@@ -14,6 +14,7 @@ public class FieldDescriptorBuilder
     protected string? _format;
     protected string? _name;
     protected SequenceCollection? _sequences;
+    protected string? _dataSourceTypeName;
 
     protected internal FieldDescriptorBuilder(Type runtimeType)
     {
@@ -38,8 +39,14 @@ public FieldDescriptorBuilder WithSequence(string pattern, string? value)
         return this;
     }
 
+    public FieldDescriptorBuilder WithDataSourceTypeName(string typeName)
+    {
+        _dataSourceTypeName = typeName;
+        return this;
+    }
+
     public virtual FieldDescriptor Build()
     {
-        return new FieldDescriptor(_runtimeType, _name, _format, _sequences?.ToImmutable());
+        return new FieldDescriptor(_runtimeType, _name, _format, _sequences?.ToImmutable(), _dataSourceTypeName ?? string.Empty);
     }
 }

PocketCsvReader/Configuration/NumericFieldDescriptorBuilder.cs

@@ -41,6 +41,9 @@ public NumericFieldDescriptorBuilder WithoutGroupChar()
     public new NumericFieldDescriptorBuilder WithSequence(string pattern, string? value)
         => (NumericFieldDescriptorBuilder)base.WithSequence(pattern, value);
 
+    public new NumericFieldDescriptorBuilder WithDataSourceTypeName(string typeName)
+        => (NumericFieldDescriptorBuilder)base.WithDataSourceTypeName(typeName);
+
     public override FieldDescriptor Build()
-        => new NumericFieldDescriptor(_runtimeType, _name, _format, _sequences?.ToImmutable(), _decimalChar, _groupChar);
+        => new NumericFieldDescriptor(_runtimeType, _name, _format, _sequences?.ToImmutable(), _dataSourceTypeName ?? string.Empty, _decimalChar, _groupChar);
 }