StreamExtensions mit UnitTests versehen

AMWD.Common.Tests/Extensions/StreamExtensionsTests.cs

@@ -0,0 +1,138 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace AMWD.Common.Tests.Extensions
+{
+	[TestClass]
+	public class StreamExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReadLineFromStreamSynchronous()
+		{
+			// arrange
+			var sb = new StringBuilder();
+			sb.AppendLine("First Line");
+			sb.AppendLine("Second Line");
+			byte[] buffer = Encoding.UTF8.GetBytes(sb.ToString().Trim());
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = stream.ReadLine();
+
+			// assert
+			Assert.AreEqual("First Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public void ShouldReadUntilEndAsLineSynchronous()
+		{
+			// arrange
+			byte[] buffer = Encoding.UTF8.GetBytes("Single Line");
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = stream.ReadLine();
+
+			// assert
+			Assert.AreEqual("Single Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public void ShouldReturnNullWhenNotReadableSynchronous()
+		{
+			// arrange
+			var stream = new WriteOnlyStream();
+
+			// act
+			string line = stream.ReadLine();
+
+			// assert
+			Assert.IsNull(line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public async Task ShouldReadLineFromStreamAsynchronous()
+		{
+			// arrange
+			var sb = new StringBuilder();
+			sb.AppendLine("First Line");
+			sb.AppendLine("Second Line");
+			byte[] buffer = Encoding.UTF8.GetBytes(sb.ToString().Trim());
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = await stream.ReadLineAsync();
+
+			// assert
+			Assert.AreEqual("First Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public async Task ShouldReadUntilEndAsLineAsynchronous()
+		{
+			// arrange
+			byte[] buffer = Encoding.UTF8.GetBytes("Single Line");
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = await stream.ReadLineAsync();
+
+			// assert
+			Assert.AreEqual("Single Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public async Task ShouldReturnNullWhenNotReadableAsynchronous()
+		{
+			// arrange
+			var stream = new WriteOnlyStream();
+
+			// act
+			string line = await stream.ReadLineAsync();
+
+			// assert
+			Assert.IsNull(line);
+
+			stream.Dispose();
+		}
+
+		private class WriteOnlyStream : Stream
+		{
+			public override bool CanRead => false;
+
+			public override bool CanSeek => false;
+
+			public override bool CanWrite => true;
+
+			public override long Length => 0;
+
+			public override long Position { get => 0; set => throw new NotImplementedException(); }
+
+			public override void Flush()
+			{ }
+
+			public override int Read(byte[] buffer, int offset, int count) => 0;
+
+			public override long Seek(long offset, SeekOrigin origin) => 0;
+
+			public override void SetLength(long value)
+			{ }
+
+			public override void Write(byte[] buffer, int offset, int count)
+			{ }
+		}
+	}
+}

AMWD.Common/Extensions/StreamExtensions.cs

@@ -1,27 +1,36 @@
-using System;
-using System.Collections.Generic;
-using System.IO;
+using System.Collections.Generic;
+using System.Linq;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
 
-namespace AMWD.Common.Extensions
+namespace System.IO
 {
+	/// <summary>
+	/// Provides extension methods for the <see cref="Stream"/>.
+	/// </summary>
 	public static class StreamExtensions
 	{
-		public static string ReadLine(this Stream stream, Encoding encoding = null, string eol = null)
+		/// <summary>
+		/// Reads a line from a <see cref="Stream"/>.
+		/// </summary>
+		/// <param name="stream">The stream to read from.</param>
+		/// <param name="encoding">The encoding to use.</param>
+		/// <param name="eol">The character determinating a line end.</param>
+		/// <returns></returns>
+		public static string ReadLine(this Stream stream, Encoding encoding = null, char? eol = null)
 		{
 			if (encoding == null)
 				encoding = Encoding.Default;
 
 			if (eol == null)
-				eol = Environment.NewLine;
+				eol = Environment.NewLine.Last();
 
 			if (!stream.CanRead)
 				return null;
 
 			var bytes = new List<byte>();
-			string s;
+			char ch;
 			do
 			{
 				int result = stream.ReadByte();
@@ -30,37 +39,45 @@ namespace AMWD.Common.Extensions
 
 				byte b = (byte)result;
 				bytes.Add(b);
-				s = encoding.GetString(new[] { b });
+				ch = (char)result;
 			}
-			while (!eol.Contains(s));
+			while (ch != eol);
 
 			return encoding.GetString(bytes.ToArray()).Trim();
 		}
 
-		public static async Task<string> ReadLineAsync(this Stream stream, Encoding encoding = null, string eol = null, CancellationToken cancellationToken = default)
+		/// <summary>
+		/// Reads a line from a <see cref="Stream"/> asynchronous.
+		/// </summary>
+		/// <param name="stream">The stream to read from.</param>
+		/// <param name="encoding">The encoding to use.</param>
+		/// <param name="eol">The character determinating a line end.</param>
+		/// <param name="cancellationToken">The token to monitor for cancellation requests. The default value is <see cref="CancellationToken.None"/>.</param>
+		/// <returns></returns>
+		public static async Task<string> ReadLineAsync(this Stream stream, Encoding encoding = null, char? eol = null, CancellationToken cancellationToken = default)
 		{
 			if (encoding == null)
 				encoding = Encoding.Default;
 
 			if (eol == null)
-				eol = Environment.NewLine;
+				eol = Environment.NewLine.Last();
 
 			if (!stream.CanRead)
 				return null;
 
 			var bytes = new List<byte>();
-			string s;
+			char ch;
 			do
 			{
 				byte[] buffer = new byte[1];
-				int count = await stream.ReadAsync(buffer, 0, buffer.Length);
+				int count = await stream.ReadAsync(buffer, 0, buffer.Length, cancellationToken);
 				if (count == 0)
 					break;
 
 				bytes.Add(buffer[0]);
-				s = encoding.GetString(buffer);
+				ch = (char)buffer[0];
 			}
-			while (!eol.Contains(s));
+			while (ch != eol);
 
 			return encoding.GetString(bytes.ToArray()).Trim();
 		}

CHANGELOG.md

@@ -8,6 +8,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 - CHANGELOG
 - `HtmlHelper.IsDarkColor` to classify a color as dark or light one (by luminance)
+- `ReadLine` and `ReadLineAsync` as `StreamExtensions`
+
 
 ### Changed
 - Unit-Tests enhanced