From 2efe3a4f200c91a43a2c5d6fe53064898994e5a8 Mon Sep 17 00:00:00 2001
From: Josh Close <narshe@gmail.com>
Date: Thu, 29 Feb 2024 14:52:21 -0600
Subject: [PATCH] Removed dependency on System.Linq.Async. Updated package
 reference versions.

---
 src/CsvHelper/CsvHelper.csproj                | 31 ++++++++-----------
 src/CsvHelper/CsvWriter.cs                    |  7 +++--
 .../Compatibility/IsExternalInit.cs           |  6 ++++
 tests/CsvHelper.Tests/CsvHelper.Tests.csproj  |  6 ++--
 4 files changed, 27 insertions(+), 23 deletions(-)
 create mode 100644 tests/CsvHelper.Tests/Compatibility/IsExternalInit.cs

diff --git a/src/CsvHelper/CsvHelper.csproj b/src/CsvHelper/CsvHelper.csproj
index f080bc528..3d821abd2 100644
--- a/src/CsvHelper/CsvHelper.csproj
+++ b/src/CsvHelper/CsvHelper.csproj
@@ -48,46 +48,41 @@
 		<None Include="Icon.png" Pack="true" PackagePath="\" />
 	</ItemGroup>
 
-	<!-- All .NET Versions-->
-	<ItemGroup>
-		<PackageReference Include="System.Linq.Async" Version="4.0.0" />
-	</ItemGroup>
-
 	<!-- .NET 4.6.2 -->
 	<ItemGroup Condition="'$(TargetFramework)' == 'net462'">
-		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.0.0" />
-		<PackageReference Include="Microsoft.CSharp" Version="4.3.0" />
+		<PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="7.0.0" />
+		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.1.1" />
+		<PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
 		<PackageReference Include="System.Memory" Version="4.5.0" />
-		<PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
 	</ItemGroup>
 
 	<!-- .NET 4.7 -->
 	<ItemGroup Condition="'$(TargetFramework)' == 'net47'">
-		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.0.0" />
-		<PackageReference Include="Microsoft.CSharp" Version="4.3.0" />
+		<PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="7.0.0" />
+		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.1.1" />
+		<PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
 		<PackageReference Include="System.Memory" Version="4.5.0" />
-		<PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
 	</ItemGroup>
 
 	<!-- .NET 4.8 -->
 	<ItemGroup Condition="'$(TargetFramework)' == 'net48'">
-		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.0.0" />
-		<PackageReference Include="Microsoft.CSharp" Version="4.3.0" />
+		<PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="7.0.0" />
+		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.1.1" />
+		<PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
 		<PackageReference Include="System.Memory" Version="4.5.0" />
-		<PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
 	</ItemGroup>
 
 	<!-- .NET Standard 2.0 -->
 	<ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.0'">
-		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.0.0" />
-		<PackageReference Include="Microsoft.CSharp" Version="4.3.0" />
+		<PackageReference Include="Microsoft.Bcl.AsyncInterfaces" Version="7.0.0" />
+		<PackageReference Include="Microsoft.Bcl.HashCode" Version="1.1.1" />
+		<PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
 		<PackageReference Include="System.Memory" Version="4.5.0" />
-		<PackageReference Include="System.Threading.Tasks.Extensions" Version="4.5.2" />
 	</ItemGroup>
 
 	<!-- .NET Standard 2.1 -->
 	<ItemGroup Condition="'$(TargetFramework)' == 'netstandard2.1'">
-		<PackageReference Include="Microsoft.CSharp" Version="4.3.0" />
+		<PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
 	</ItemGroup>
 
 	<ItemGroup>
diff --git a/src/CsvHelper/CsvWriter.cs b/src/CsvHelper/CsvWriter.cs
index e3db3db8b..b5d3f1dd3 100644
--- a/src/CsvHelper/CsvWriter.cs
+++ b/src/CsvHelper/CsvWriter.cs
@@ -6,7 +6,6 @@
 using CsvHelper.Expressions;
 using CsvHelper.TypeConversion;
 using System;
-using System.Buffers;
 using System.Collections;
 using System.Collections.Generic;
 using System.Dynamic;
@@ -773,7 +772,11 @@ private async Task<bool> WriteHeaderAsync<T>(IAsyncEnumerable<T> records)
 				return hasHeaderBeenWritten;
 			}
 
-			return WriteHeader(await records.FirstOrDefaultAsync());
+			var enumerator = records.GetAsyncEnumerator();
+			await enumerator.MoveNextAsync().ConfigureAwait(false);
+			var header = enumerator.Current;
+
+			return WriteHeader(header);
 		}
 
 		private bool WriteHeader<T>(IEnumerable<T> records)
diff --git a/tests/CsvHelper.Tests/Compatibility/IsExternalInit.cs b/tests/CsvHelper.Tests/Compatibility/IsExternalInit.cs
new file mode 100644
index 000000000..b2942b517
--- /dev/null
+++ b/tests/CsvHelper.Tests/Compatibility/IsExternalInit.cs
@@ -0,0 +1,6 @@
+#if NETFRAMEWORK
+namespace System.Runtime.CompilerServices
+{
+	internal static class IsExternalInit { }
+}
+#endif
diff --git a/tests/CsvHelper.Tests/CsvHelper.Tests.csproj b/tests/CsvHelper.Tests/CsvHelper.Tests.csproj
index ce060e13c..720f7cfb6 100644
--- a/tests/CsvHelper.Tests/CsvHelper.Tests.csproj
+++ b/tests/CsvHelper.Tests/CsvHelper.Tests.csproj
@@ -1,8 +1,8 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
 	<PropertyGroup>
-		<!--<TargetFrameworks>net8.0;net7.0;net6.0;net48;net47;net462</TargetFrameworks>-->
-		<TargetFrameworks>net8.0</TargetFrameworks>
+		<TargetFrameworks>net8.0;net7.0;net6.0;net48;net47;net462</TargetFrameworks>
+		<!--<TargetFrameworks>net8.0</TargetFrameworks>-->
 		<LangVersion>preview</LangVersion>
 		<SignAssembly>True</SignAssembly>
 		<AssemblyOriginatorKeyFile>CsvHelper.snk</AssemblyOriginatorKeyFile>
@@ -16,7 +16,7 @@
 		<PackageReference Include="Castle.Core" Version="4.4.1" />
 		<PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.10.0" />
 		<PackageReference Include="Microsoft.CSharp" Version="4.7.0" />
-		<PackageReference Include="System.Linq.Async" Version="5.0.0" />
+		<PackageReference Include="System.Linq.Async" Version="6.0.1" />
 		<PackageReference Include="xunit" Version="2.4.1" />
 		<PackageReference Include="xunit.runner.visualstudio" Version="2.4.3">
 			<IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>