Add hasHeader flag in ColumnInference function

src/Microsoft.ML.AutoML/ColumnInference/ColumnInferenceApi.cs

@@ -36,12 +36,12 @@ public static ColumnInferenceResults InferColumns(MLContext context, string path
         }
 
         public static ColumnInferenceResults InferColumns(MLContext context, string path, ColumnInformation columnInfo,
-            char? separatorChar, bool? allowQuotedStrings, bool? supportSparse, bool trimWhitespace, bool groupColumns)
+            char? separatorChar, bool? allowQuotedStrings, bool? supportSparse, bool trimWhitespace, bool groupColumns, bool hasHeader = true)
         {
             var sample = TextFileSample.CreateFromFullFile(path);
             var splitInference = InferSplit(context, sample, separatorChar, allowQuotedStrings, supportSparse);
-            var typeInference = InferColumnTypes(context, sample, splitInference, true, null, columnInfo.LabelColumnName);
-            return InferColumns(context, path, columnInfo, true, splitInference, typeInference, trimWhitespace, groupColumns);
+            var typeInference = InferColumnTypes(context, sample, splitInference, hasHeader, null, columnInfo.LabelColumnName);
+            return InferColumns(context, path, columnInfo, hasHeader, splitInference, typeInference, trimWhitespace, groupColumns);
         }
 
         public static ColumnInferenceResults InferColumns(MLContext context, string path, ColumnInformation columnInfo, bool hasHeader,

test/Microsoft.ML.AutoML.Tests/ColumnInferenceTests.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using Microsoft.ML.Data;
@@ -91,6 +92,35 @@ public void DatasetWithBoolColumn()
             Assert.Equal(DefaultColumnNames.Label, result.ColumnInformation.LabelColumnName);
         }
 
+        [Fact]
+        public void InferDatasetWithoutHeader()
+        {
+            var context = new MLContext(1);
+            var filePath = Path.Combine("TestData", "DatasetWithoutHeader.txt");
+            var columnInfo = new ColumnInformation()
+            {
+                LabelColumnName = "col0",
+                UserIdColumnName = "col1",
+                ItemIdColumnName = "col2",
+            };
+            columnInfo.IgnoredColumnNames.Add("col4");
+            var result = ColumnInferenceApi.InferColumns(context, filePath, columnInfo, ',', null, null, false, false, false);
+            Assert.Equal(6, result.TextLoaderOptions.Columns.Count());
+
+            var labelColumn = result.TextLoaderOptions.Columns.First(c => c.Name == "col0");
+            var userColumn = result.TextLoaderOptions.Columns.First(c => c.Name == "col1");
+            var itemColumn = result.TextLoaderOptions.Columns.First(c => c.Name == "col2");
+            var ignoreColumn = result.TextLoaderOptions.Columns.First(c => c.Name == "col4");
+
+            Assert.Equal(DataKind.String, labelColumn.DataKind);
+            Assert.Equal(DataKind.Single, userColumn.DataKind);
+            Assert.Equal(DataKind.Single, itemColumn.DataKind);
+            Assert.Equal(DataKind.Single, ignoreColumn.DataKind);
+
+            Assert.Single(result.ColumnInformation.CategoricalColumnNames);
+            Assert.Empty(result.ColumnInformation.TextColumnNames);
+        }
+
         [Fact]
         public void WhereNameColumnIsOnlyFeature()
         {

test/Microsoft.ML.AutoML.Tests/Microsoft.ML.AutoML.Tests.csproj

@@ -14,6 +14,9 @@
     <None Update="TestData\DatasetWithDefaultColumnNames.txt">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>
+    <None Update="TestData\DatasetWithoutHeader.txt">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </None>
     <None Update="TestData\NameColumnIsOnlyFeatureDataset.txt">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </None>

test/Microsoft.ML.AutoML.Tests/TestData/DatasetWithoutHeader.txt

@@ -0,0 +1,20 @@
+CMT,1271,3.8,CRD,17.5,T
+CMT,474,1.5,CRD,8,T
+CMT,637,1.4,CRD,8.5,T
+CMT,181,0.6,CSH,4.5,T
+CMT,661,1.1,CRD,8.5,T
+CMT,935,9.6,CSH,27.5,T
+CMT,869,2.3,CRD,11.5,T
+CMT,454,1.4,CRD,7.5,T
+CMT,366,1.5,CSH,7.5,T
+VTS,1140,5.61,CSH,18.5,F
+VTS,120,0.67,CSH,4,F
+VTS,240,1.7,CRD,6.5,F
+VTS,660,2.52,CRD,10.5,F
+VTS,420,0.82,CSH,6,F
+VTS,420,1.04,CRD,6.5,F
+VTS,2280,18,CRD,52,F
+VTS,360,1.2,CRD,6.5,F
+VTS,660,2.22,CSH,10,F
+VTS,840,3.29,CSH,12.5,F
+VTS,540,1.85,CRD,8.5,F