Merge branch 'Rob-Hague-columncount'

JoshClose · Jan 24, 2024 · 356f84e · 356f84e
2 parents 1415c93 + 4814452
commit 356f84e
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Showing 2 changed files with 47 additions and 6 deletions.
diff --git a/src/CsvHelper/CsvReader.cs b/src/CsvHelper/CsvReader.cs
@@ -41,13 +41,13 @@ public class CsvReader : IReader
 		private CsvContext context;
 		private bool disposed;
 		private IParser parser;
-		private int columnCount;
+		private int prevColumnCount;
 		private int currentIndex = -1;
 		private bool hasBeenRead;
 		private string[] headerRecord;
 
 		/// <inheritdoc/>
-		public virtual int ColumnCount => columnCount;
+		public virtual int ColumnCount => parser.Count;
 
 		/// <inheritdoc/>
 		public virtual int CurrentIndex => currentIndex;
@@ -260,7 +260,7 @@ public virtual bool Read()
 
 			if (detectColumnCountChanges && hasMoreRecords)
 			{
-				if (columnCount > 0 && columnCount != parser.Count)
+				if (prevColumnCount > 0 && prevColumnCount != parser.Count)
 				{
 					var csvException = new BadDataException(string.Empty, parser.RawRecord, context, "An inconsistent number of columns has been detected.");
 
@@ -271,7 +271,7 @@ public virtual bool Read()
 					}
 				}
 
-				columnCount = parser.Count;
+				prevColumnCount = parser.Count;
 			}
 
 			return hasMoreRecords;
@@ -292,7 +292,7 @@ public virtual async Task<bool> ReadAsync()
 
 			if (detectColumnCountChanges && hasMoreRecords)
 			{
-				if (columnCount > 0 && columnCount != parser.Count)
+				if (prevColumnCount > 0 && prevColumnCount != parser.Count)
 				{
 					var csvException = new BadDataException(string.Empty, parser.RawRecord, context, "An inconsistent number of columns has been detected.");
 
@@ -303,7 +303,7 @@ public virtual async Task<bool> ReadAsync()
 					}
 				}
 
-				columnCount = parser.Count;
+				prevColumnCount = parser.Count;
 			}
 
 			return hasMoreRecords;

diff --git a/tests/CsvHelper.Tests/CsvReaderTests.cs b/tests/CsvHelper.Tests/CsvReaderTests.cs
@@ -50,6 +50,47 @@ public void HasHeaderRecordTest()
 			Assert.Equal(Convert.ToInt32("2"), reader.GetField<int>(1));
 		}
 
+		[Theory]
+		[InlineData(true)]
+		[InlineData(false)]
+		public void ColumnCountTest(bool detectColumnCountChanges)
+		{
+			var config = new CsvConfiguration(CultureInfo.InvariantCulture)
+			{
+				DetectColumnCountChanges = detectColumnCountChanges,
+				ReadingExceptionOccurred = _ => false
+			};
+
+			string csvString = """
+				1
+				1,2
+				1,2,3
+				1,2
+				1
+				""";
+			var reader = new CsvReader(new StringReader(csvString), config);
+
+			Assert.True(reader.Read());
+			Assert.Equal(1, reader.ColumnCount);
+			Assert.Equal(reader.Parser.Count, reader.ColumnCount);
+
+			Assert.True(reader.Read());
+			Assert.Equal(2, reader.ColumnCount);
+			Assert.Equal(reader.Parser.Count, reader.ColumnCount);
+
+			Assert.True(reader.Read());
+			Assert.Equal(3, reader.ColumnCount);
+			Assert.Equal(reader.Parser.Count, reader.ColumnCount);
+
+			Assert.True(reader.Read());
+			Assert.Equal(2, reader.ColumnCount);
+			Assert.Equal(reader.Parser.Count, reader.ColumnCount);
+
+			Assert.True(reader.Read());
+			Assert.Equal(1, reader.ColumnCount);
+			Assert.Equal(reader.Parser.Count, reader.ColumnCount);
+		}
+
 		[Fact]
 		public void GetTypeTest()
 		{