From 93265d2453e7904d8153d0c0a546943857d9cc76 Mon Sep 17 00:00:00 2001
From: Richard Webb <webby@beardmouse.co.uk>
Date: Mon, 1 Mar 2021 15:18:28 +0000
Subject: [PATCH] add a simple async read test for ZipFile

---
 .../Zip/ZipFileHandling.cs                    | 24 +++++++++++
 .../Zip/ZipTests.cs                           | 43 ++++++++++++++++++-
 2 files changed, 66 insertions(+), 1 deletion(-)

diff --git a/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipFileHandling.cs b/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipFileHandling.cs
index c92dae280..9d50fb844 100644
--- a/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipFileHandling.cs
+++ b/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipFileHandling.cs
@@ -5,6 +5,7 @@
 using System;
 using System.IO;
 using System.Text;
+using System.Threading.Tasks;
 
 namespace ICSharpCode.SharpZipLib.Tests.Zip
 {
@@ -582,6 +583,29 @@ public void RoundTripInMemory()
 			}
 		}
 
+		/// <summary>
+		/// Simple async round trip test for ZipFile class
+		/// </summary>
+		[TestCase(CompressionMethod.Stored)]
+		[TestCase(CompressionMethod.Deflated)]
+		[TestCase(CompressionMethod.BZip2)]
+		[Category("Zip")]
+		[Category("Async")]
+		public async Task RoundTripInMemoryAsync(CompressionMethod compressionMethod)
+		{
+			var storage = new MemoryStream();
+			MakeZipFile(storage, compressionMethod, false, "", 10, 1024, "");
+
+			using (ZipFile zipFile = new ZipFile(storage))
+			{
+				foreach (ZipEntry e in zipFile)
+				{
+					Stream instream = zipFile.GetInputStream(e);
+					await CheckKnownEntryAsync(instream, 1024);
+				}
+			}
+		}
+
 		[Test]
 		[Category("Zip")]
 		public void AddToEmptyArchive()
diff --git a/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipTests.cs b/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipTests.cs
index eff2e007b..4a0c9954f 100644
--- a/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipTests.cs
+++ b/test/ICSharpCode.SharpZipLib.Tests/Zip/ZipTests.cs
@@ -7,6 +7,7 @@
 using System.IO;
 using System.Security;
 using System.Text;
+using System.Threading.Tasks;
 
 namespace ICSharpCode.SharpZipLib.Tests.Zip
 {
@@ -288,7 +289,7 @@ protected static byte ScatterValue(byte rhs)
 			return (byte)((rhs * 253 + 7) & 0xff);
 		}
 
-		private static void AddKnownDataToEntry(ZipOutputStream zipStream, int size)
+		private static void AddKnownDataToEntry(Stream zipStream, int size)
 		{
 			if (size > 0)
 			{
@@ -387,6 +388,27 @@ protected void MakeZipFile(Stream storage, bool isOwner,
 			}
 		}
 
+		protected void MakeZipFile(Stream storage, CompressionMethod compressionMethod,  bool isOwner,
+			string entryNamePrefix, int entries, int size, string comment)
+		{
+			using (ZipFile f = new ZipFile(storage, leaveOpen: !isOwner))
+			{
+				f.BeginUpdate();
+				f.SetComment(comment);
+
+				for (int i = 0; i < entries; ++i)
+				{
+					var data = new MemoryStream();
+					AddKnownDataToEntry(data, size);
+
+					var m = new MemoryDataSource(data.ToArray());
+					f.Add(m, entryNamePrefix + (i + 1), compressionMethod);
+				}
+
+				f.CommitUpdate();
+			}
+		}
+
 		#endregion MakeZipFile Entries
 
 		protected static void CheckKnownEntry(Stream inStream, int expectedCount)
@@ -408,6 +430,25 @@ protected static void CheckKnownEntry(Stream inStream, int expectedCount)
 			Assert.AreEqual(expectedCount, total, "Wrong number of bytes read from entry");
 		}
 
+		protected static async Task CheckKnownEntryAsync(Stream inStream, int expectedCount)
+		{
+			byte[] buffer = new byte[1024];
+
+			int bytesRead;
+			int total = 0;
+			byte nextValue = 0;
+			while ((bytesRead = await inStream.ReadAsync(buffer, 0, buffer.Length)) > 0)
+			{
+				total += bytesRead;
+				for (int i = 0; i < bytesRead; ++i)
+				{
+					Assert.AreEqual(nextValue, buffer[i], "Wrong value read from entry");
+					nextValue = ScatterValue(nextValue);
+				}
+			}
+			Assert.AreEqual(expectedCount, total, "Wrong number of bytes read from entry");
+		}
+
 		protected byte ReadByteChecked(Stream stream)
 		{
 			int rawValue = stream.ReadByte();