HttpRequestStreamReader overrides for Read Span, ReadAsync Memory, ReadLine and ReadLineAsync (#18802)

Author: alefranz

src/Http/WebUtilities/perf/Microsoft.AspNetCore.WebUtilities.Performance/HttpRequestStreamReaderReadLineBenchmark.cs

@@ -0,0 +1,52 @@
+using System.Diagnostics;
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using BenchmarkDotNet.Attributes;
+
+namespace Microsoft.AspNetCore.WebUtilities
+{
+    public class HttpRequestStreamReaderReadLineBenchmark
+    {
+        private MemoryStream _stream;
+
+        [Params(200, 1000, 1025, 1600)]  // Default buffer length is 1024
+        public int Length { get; set; }
+
+        [GlobalSetup]
+        public void GlobalSetup()
+        {
+            var data = new char[Length];
+
+            data[Length - 2] = '\r';
+            data[Length - 1] = '\n';
+
+            _stream = new MemoryStream(Encoding.UTF8.GetBytes(data));
+        }
+
+        [Benchmark]
+        public async Task<string> ReadLineAsync()
+        {
+            var reader = CreateReader();
+            var result = await reader.ReadLineAsync();
+            Debug.Assert(result.Length == Length - 2);
+            return result;
+        }
+
+        [Benchmark]
+        public string ReadLine()
+        {
+            var reader = CreateReader();
+            var result = reader.ReadLine();
+            Debug.Assert(result.Length == Length - 2);
+            return result;
+        }
+
+        [Benchmark]
+        public HttpRequestStreamReader CreateReader()
+        {
+            _stream.Seek(0, SeekOrigin.Begin);
+            return new HttpRequestStreamReader(_stream, Encoding.UTF8);
+        }
+    }
+}

src/Http/WebUtilities/perf/Microsoft.AspNetCore.WebUtilities.Performance/Microsoft.AspNetCore.WebUtilities.Performance.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>$(DefaultNetCoreTargetFramework)</TargetFramework>

src/Http/WebUtilities/ref/Microsoft.AspNetCore.WebUtilities.netcoreapp.cs

@@ -145,8 +145,13 @@ protected override void Dispose(bool disposing) { }
         public override int Peek() { throw null; }
         public override int Read() { throw null; }
         public override int Read(char[] buffer, int index, int count) { throw null; }
-        [System.Diagnostics.DebuggerStepThroughAttribute]
+        public override int Read(System.Span<char> buffer) { throw null; }
         public override System.Threading.Tasks.Task<int> ReadAsync(char[] buffer, int index, int count) { throw null; }
+        [System.Diagnostics.DebuggerStepThroughAttribute]
+        public override System.Threading.Tasks.ValueTask<int> ReadAsync(System.Memory<char> buffer, System.Threading.CancellationToken cancellationToken = default(System.Threading.CancellationToken)) { throw null; }
+        public override string ReadLine() { throw null; }
+        [System.Diagnostics.DebuggerStepThroughAttribute]
+        public override System.Threading.Tasks.Task<string> ReadLineAsync() { throw null; }
     }
     public partial class HttpResponseStreamWriter : System.IO.TextWriter
     {