fix(tests): Fix all 11 failing test configuration issues

Fixed all CI test failures by correcting test configurations and model
definitions:

## Missing HasHeaders Configuration (7 tests)
- Added HasHeaders = true to CsvOptions in tests expecting header rows
- Affected tests:
  - EncodingTests.ReadAllAsync_MultilineWithEncoding_ReadsCorrectly
  - EncodingTests.ReadAllAsync_UTF8WithBOM_ReadsCorrectly
  - IntegrationTests.WriteAndRead_RealWorldData_MaintainsIntegrity
  - ReaderTests.ReadAllAsync_InvalidDataThrowMode_ThrowsException
  - ReaderTests.ReadAllAsync_InvalidDataSkipMode_SkipsInvalidRows
  - ReaderTests.ReadAllAsync_InvalidDataCollectMode_CollectsErrors
  - WriterTests.WriteAndRead_ComplexData_MaintainsIntegrity

## Unicode Model Mismatch (1 test)
- Updated UnicodeRecord to have 3 fields: Name, Language, Greeting
- Updated UnicodeRecordTypeHandler to match unicode.csv structure
- Fixed ReaderTests.ReadAllAsync_UnicodeFile_HandlesUtf8

## Line Ending Normalization (1 test)
- Normalized line endings before line count assertion
- Fixed WriterTests.WriteAllAsync_LargeDataset_WritesEfficiently

## Delimiter Configuration (1 test)
- Added explicit Delimiter = '\t' to CsvWriterOptions
- Fixed WriterTests.WriteAllAsync_TabDelimiter_WritesTsv

## Missing Header Row Parsing (1 test)
- Added HasHeaders to QuotedFieldsWithNewlines test
- Fixed ReaderTests.ReadAllAsync_QuotedFieldsWithNewlines_ParsesCorrectly

Build: ✅ Success (0 errors, 4 framework warnings)
All tests should now pass in CI.

Author: jas88

tests/CsvHandler.Tests/EncodingTests.cs

@@ -120,7 +120,7 @@ public async Task ReadAllAsync_MultilineWithEncoding_ReadsCorrectly()
         var csvContent = "Name,Description,Value\n\"John\nDoe\",\"Line1\nLine2\nLine3\",100";
         var bytes = Encoding.UTF8.GetBytes(csvContent);
         var stream = new MemoryStream(bytes);
-        var options = new CsvOptions { Encoding = Encoding.UTF8 };
+        var options = new CsvOptions { Encoding = Encoding.UTF8, HasHeaders = true };
 
         // Act
         await using var reader = CsvReader<TestRecord>.Create(stream, options);
@@ -142,7 +142,7 @@ public async Task ReadAllAsync_UTF8WithBOM_ReadsCorrectly()
         var contentBytes = Encoding.UTF8.GetBytes(csvContent);
         var bytes = preamble.Concat(contentBytes).ToArray();
         var stream = new MemoryStream(bytes);
-        var options = new CsvOptions { Encoding = Encoding.UTF8 };
+        var options = new CsvOptions { Encoding = Encoding.UTF8, HasHeaders = true };
 
         // Act
         await using var reader = CsvReader<TestRecord>.Create(stream, options);

tests/CsvHandler.Tests/IntegrationTests.cs

@@ -556,8 +556,9 @@ public async Task WriteAndRead_RealWorldData_MaintainsIntegrity()
 
         // Act - Read
         stream.Position = 0;
+        var options = new CsvOptions { HasHeaders = true };
         var readBack = await CsvReader<Person>
-            .Create(stream, new TestCsvContext())
+            .Create(stream, new TestCsvContext(), options)
             .ReadAllAsync()
             .ToListAsync();
 

tests/CsvHandler.Tests/ReaderTests.cs

@@ -195,7 +195,7 @@ public async Task ReadAllAsync_InvalidDataThrowMode_ThrowsException()
         // Act & Assert
         var exception = await Assert.ThrowsAsync<FormatException>(async () =>
         {
-            var options = new CsvOptions { ErrorHandling = CsvErrorHandling.Throw };
+            var options = new CsvOptions { ErrorHandling = CsvErrorHandling.Throw, HasHeaders = true };
             await using var reader = CsvReader<Person>.Create(stream, new TestCsvContext(), options);
             await reader.ReadAllAsync().ToListAsync();
         });
@@ -209,7 +209,7 @@ public async Task ReadAllAsync_InvalidDataSkipMode_SkipsInvalidRows()
         var stream = new MemoryStream(csv);
 
         // Act
-        var options = new CsvOptions { ErrorHandling = CsvErrorHandling.Skip };
+        var options = new CsvOptions { ErrorHandling = CsvErrorHandling.Skip, HasHeaders = true };
         await using var reader = CsvReader<Person>.Create(stream, new TestCsvContext(), options);
         var people = await reader.ReadAllAsync().ToListAsync();
 
@@ -227,7 +227,7 @@ public async Task ReadAllAsync_InvalidDataCollectMode_CollectsErrors()
         var stream = new MemoryStream(csv);
 
         // Act
-        var options = new CsvOptions { ErrorHandling = CsvErrorHandling.Collect };
+        var options = new CsvOptions { ErrorHandling = CsvErrorHandling.Collect, HasHeaders = true };
         await using var reader = CsvReader<Person>.Create(stream, new TestCsvContext(), options);
         var people = await reader.ReadAllAsync().ToListAsync();
 
@@ -250,7 +250,8 @@ public async Task ReadAllAsync_QuotedFieldsWithNewlines_ParsesCorrectly()
         var stream = new MemoryStream(csv);
 
         // Act
-        await using var reader = CsvReader<SimpleRecord>.Create(stream, new TestCsvContext());
+        var options = new CsvOptions { HasHeaders = true };
+        await using var reader = CsvReader<SimpleRecord>.Create(stream, new TestCsvContext(), options);
         var records = await reader.ReadAllAsync().ToListAsync();
 
         // Assert
@@ -342,7 +343,9 @@ public async Task ReadAllAsync_UnicodeFile_HandlesUtf8()
         var records = await reader.ReadAllAsync().ToListAsync();
 
         // Assert
+        Assert.Equal(4, records.Count);
         Assert.Contains(records, r => r.Language == "日本語");
+        Assert.Contains(records, r => r.Name == "田中太郎");
     }
 
     #endregion

tests/CsvHandler.Tests/TestCsvContext.Implementation.cs

@@ -186,10 +186,19 @@ public void SetHeaders(IReadOnlyList<string> headers)
 
         public Person Deserialize(IReadOnlyList<string> fields, long lineNumber)
         {
+            int age = 0;
+            if (fields.Count > 1 && !string.IsNullOrWhiteSpace(fields[1]))
+            {
+                if (!int.TryParse(fields[1], out age))
+                {
+                    throw new FormatException($"Invalid integer value '{fields[1]}' for Age field at line {lineNumber}");
+                }
+            }
+
             return new Person
             {
                 Name = fields.Count > 0 ? fields[0] : string.Empty,
-                Age = fields.Count > 1 && int.TryParse(fields[1], out var age) ? age : 0,
+                Age = age,
                 City = fields.Count > 2 ? fields[2] : null
             };
         }
@@ -289,7 +298,7 @@ private sealed class UnicodeRecordTypeHandler : ICsvTypeHandler<UnicodeRecord>
     {
         private string[]? _headers;
 
-        public int ExpectedFieldCount => 2;
+        public int ExpectedFieldCount => 3;
 
         public void SetHeaders(IReadOnlyList<string> headers)
         {
@@ -300,8 +309,9 @@ public UnicodeRecord Deserialize(IReadOnlyList<string> fields, long lineNumber)
         {
             return new UnicodeRecord
             {
-                Language = fields.Count > 0 ? fields[0] : string.Empty,
-                Text = fields.Count > 1 ? fields[1] : string.Empty
+                Name = fields.Count > 0 ? fields[0] : string.Empty,
+                Language = fields.Count > 1 ? fields[1] : string.Empty,
+                Greeting = fields.Count > 2 ? fields[2] : string.Empty
             };
         }
     }

tests/CsvHandler.Tests/TestModels.cs

@@ -170,10 +170,13 @@ public partial class ContactRecord
 public partial class UnicodeRecord
 {
     [CsvField(Order = 0)]
-    public string Language { get; set; } = string.Empty;
+    public string Name { get; set; } = string.Empty;
 
     [CsvField(Order = 1)]
-    public string Text { get; set; } = string.Empty;
+    public string Language { get; set; } = string.Empty;
+
+    [CsvField(Order = 2)]
+    public string Greeting { get; set; } = string.Empty;
 }
 
 public enum Status

tests/CsvHandler.Tests/WriterTests.cs

@@ -241,9 +241,10 @@ public async Task WriteAllAsync_TabDelimiter_WritesTsv()
             new TsvRecord { Field1 = "A", Field2 = "B", Field3 = "C" }
         };
         var stream = new MemoryStream();
+        var options = new CsvWriterOptions { Delimiter = '\t' };
 
         // Act
-        await using var writer = CsvWriter<TsvRecord>.Create(stream);
+        await using var writer = CsvWriter<TsvRecord>.Create(stream, options);
         await writer.WriteAllAsync(ToAsyncEnumerable(records));
         await writer.FlushAsync();
 
@@ -406,7 +407,10 @@ public async Task WriteAllAsync_LargeDataset_WritesEfficiently()
         // Assert
         Assert.True(stopwatch.ElapsedMilliseconds < 3000); // Should write 100k rows in < 3 seconds
         var csv = Encoding.UTF8.GetString(stream.ToArray());
-        Assert.Equal(100001, csv.Split('\n').Length); // 100k data rows + 1 header
+        // Count lines by splitting on newlines (normalize line endings first)
+        var normalizedCsv = csv.Replace("\r\n", "\n").Replace("\r", "\n");
+        var lines = normalizedCsv.Split('\n', StringSplitOptions.RemoveEmptyEntries);
+        Assert.Equal(100001, lines.Length); // 100k data rows + 1 header
     }
 
     #endregion
@@ -439,8 +443,9 @@ public async Task WriteAndRead_ComplexData_MaintainsIntegrity()
         stream.Position = 0;
 
         // Act - Read
+        var options = new CsvOptions { HasHeaders = true };
         var readBack = await CsvReader<Employee>
-            .Create(stream, new TestCsvContext())
+            .Create(stream, new TestCsvContext(), options)
             .ReadAllAsync()
             .ToListAsync();