Merge pull request #9 from xledger/fixes

Revert incorrect "fix" and improve test.

Author: isaksky

Xledger.Collections.Test/TestMemoryOwner.cs

@@ -26,15 +26,19 @@ public void TestSlice() {
 #if NET
     [Fact]
     public void TestStream_ToMemoryOwner() {
-        byte[] array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+        // This length should be larger than the default GetCopyBufferSize.
+        byte[] array = new byte[4 * 1024 * 1024 + 3];
+        new Random().NextBytes(array);
         var ms = new MemoryStream(array);
         using var memoryOwner = ms.ToOwnedMemory();
         Assert.Equal(array.AsMemory(), memoryOwner.Memory);
     }
 
     [Fact]
     public async Task TestStream_ToMemoryOwnerAsync() {
-        byte[] array = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
+        // This length should be larger than the default GetCopyBufferSize.
+        byte[] array = new byte[4 * 1024 * 1024 + 3];
+        new Random().NextBytes(array);
         var ms = new MemoryStream(array);
         using var memoryOwner = await ms.ToOwnedMemoryAsync();
         Assert.Equal(array.AsMemory(), memoryOwner.Memory);

Xledger.Collections/Memory/Extensions.cs

@@ -38,7 +38,9 @@ public static IMemoryOwner<byte> ToOwnedMemory(this Stream source, bool leaveOpe
 
         try {
             while (true) {
-                int bytesRead = source.Read(currentBuffer.Span);
+                var dest = currentBuffer.Slice(totalBytesRead);
+
+                int bytesRead = source.Read(dest.Span);
 
                 if (bytesRead == 0) {
                     break;
@@ -100,7 +102,9 @@ public static async Task<IMemoryOwner<byte>> ToOwnedMemoryAsync(this Stream sour
             while (true) {
                 tok.ThrowIfCancellationRequested();
 
-                int bytesRead = await source.ReadAsync(currentBuffer, tok).ConfigureAwait(false);
+                var dest = currentBuffer.Slice(totalBytesRead);
+
+                int bytesRead = await source.ReadAsync(dest, tok).ConfigureAwait(false);
 
                 if (bytesRead == 0) {
                     break;