Add test where comma is in header

Author: dakersnar

test/Microsoft.Data.Analysis.Tests/DataFrame.IOTests.cs

@@ -554,6 +554,51 @@ void Verify(DataFrame df)
             Verify(df);
         }
 
+        [Fact]
+        public void TestReadCsvWithCommaSeparatorsInHeaderData()
+        {
+            string data = @"""Na,me"",Age,Description
+Paul,34,""Paul lives in Vermont, VA.""
+Victor,29,""Victor: Funny guy""
+Maria,31,";
+
+            void Verify(DataFrame df)
+            {
+                Assert.Equal(3, df.Rows.Count);
+                Assert.Equal(3, df.Columns.Count);
+
+                Assert.True(typeof(string) == df.Columns[0].DataType);
+                Assert.True(typeof(int) == df.Columns[1].DataType);
+                Assert.True(typeof(string) == df.Columns[2].DataType);
+
+
+                Assert.Equal("Na,me", df.Columns[0].Name);
+                Assert.Equal("Age", df.Columns[1].Name);
+                Assert.Equal("Description", df.Columns[2].Name);
+                VerifyColumnTypes(df);
+
+                var paulRow = df.Rows[0];
+                Assert.Equal("Paul", paulRow[0]);
+                Assert.Equal(34, paulRow[1]);
+                Assert.Equal("Paul lives in Vermont, VA.", paulRow[2]);
+
+                var victorRow = df.Rows[1];
+                Assert.Equal("Victor", victorRow[0]);
+                Assert.Equal(29, victorRow[1]);
+                Assert.Equal("Victor: Funny guy", victorRow[2]);
+
+                var mariaRow = df.Rows[2];
+                Assert.Equal("Maria", mariaRow[0]);
+                Assert.Equal(31, mariaRow[1]);
+                Assert.Equal("", mariaRow[2]);
+            }
+
+            DataFrame df = DataFrame.LoadCsv(GetStream(data), dataTypes: new Type[] { typeof(string), typeof(int), typeof(string) });
+            Verify(df);
+            df = DataFrame.LoadCsvFromString(data, dataTypes: new Type[] { typeof(string), typeof(int), typeof(string) });
+            Verify(df);
+        }
+
         [Fact]
         public void TestReadCsvWithNewlinesInData()
         {