public async Task FileBufferingReadStream_UsingMemoryStream_RentsAndReturnsRentedBuffer_WhenCopyingFromMemoryStreamDuringReadAsync()
{
var inner = MakeStream(1024 * 1024 + 25);
string tempFileName;
var arrayPool = new Mock <ArrayPool <byte> >();
arrayPool.Setup(p => p.Rent(It.IsAny <int>()))
.Returns((int m) => ArrayPool <byte> .Shared.Rent(m));
arrayPool.Setup(p => p.Return(It.IsAny <byte[]>(), It.IsAny <bool>()))
.Callback((byte[] bytes, bool clear) => ArrayPool <byte> .Shared.Return(bytes, clear));
using (var stream = new FileBufferingReadStream(inner, 1024 * 1024 + 1, 2 * 1024 * 1024, GetCurrentDirectory(), arrayPool.Object))
{
arrayPool.Verify(v => v.Rent(It.IsAny <int>()), Times.Never());
await stream.ReadAsync(new byte[1024 * 1024]);
Assert.False(File.Exists(stream.TempFileName), "tempFile should not be created as yet");
await stream.ReadAsync(new byte[4]);
Assert.True(File.Exists(stream.TempFileName), "tempFile should be created");
tempFileName = stream.TempFileName !;
arrayPool.Verify(v => v.Rent(It.IsAny <int>()), Times.Once());
arrayPool.Verify(v => v.Return(It.IsAny <byte[]>(), It.IsAny <bool>()), Times.Once());
}
Assert.False(File.Exists(tempFileName));
}
public async Task FileBufferingReadStream_AsyncReadWithOnDiskLimit_EnforcesLimit()
{
var inner = MakeStream(1024 * 2);
string tempFileName;
using (var stream = new FileBufferingReadStream(inner, 512, 1024, GetCurrentDirectory()))
{
var bytes = new byte[500];
var read0 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(bytes.Length, read0);
Assert.Equal(read0, stream.Length);
Assert.Equal(read0, stream.Position);
Assert.True(stream.InMemory);
Assert.Null(stream.TempFileName);
var read1 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(bytes.Length, read1);
Assert.Equal(read0 + read1, stream.Length);
Assert.Equal(read0 + read1, stream.Position);
Assert.False(stream.InMemory);
Assert.NotNull(stream.TempFileName);
tempFileName = stream.TempFileName !;
Assert.True(File.Exists(tempFileName));
var exception = await Assert.ThrowsAsync <IOException>(() => stream.ReadAsync(bytes, 0, bytes.Length));
Assert.Equal("Buffer limit exceeded.", exception.Message);
Assert.False(stream.InMemory);
Assert.NotNull(stream.TempFileName);
}
Assert.False(File.Exists(tempFileName));
}
public async Task FileBufferingReadStream_AsyncReadOverThreshold_CreatesFile()
{
var inner = MakeStream(1024 * 2);
string tempFileName;
using (var stream = new FileBufferingReadStream(inner, 1024, null, GetCurrentDirectory()))
{
var bytes = new byte[1000];
var read0 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(bytes.Length, read0);
Assert.Equal(read0, stream.Length);
Assert.Equal(read0, stream.Position);
Assert.True(stream.InMemory);
Assert.Null(stream.TempFileName);
var read1 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(bytes.Length, read1);
Assert.Equal(read0 + read1, stream.Length);
Assert.Equal(read0 + read1, stream.Position);
Assert.False(stream.InMemory);
Assert.NotNull(stream.TempFileName);
tempFileName = stream.TempFileName !;
Assert.True(File.Exists(tempFileName));
var read2 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(inner.Length - read0 - read1, read2);
Assert.Equal(read0 + read1 + read2, stream.Length);
Assert.Equal(read0 + read1 + read2, stream.Position);
Assert.False(stream.InMemory);
Assert.NotNull(stream.TempFileName);
Assert.True(File.Exists(tempFileName));
var read3 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(0, read3);
}
Assert.False(File.Exists(tempFileName));
}
public async Task PartialReadAsyncThenSeekReplaysBuffer()
{
var data = Enumerable.Range(0, 1024).Select(b => (byte)b).ToArray();
var inner = new MemoryStream(data);
using var stream = new FileBufferingReadStream(inner, 1024 * 1024, bufferLimit: null, GetCurrentDirectory());
var withoutBufferMs = new MemoryStream();
var buffer = new byte[100];
var read1 = await stream.ReadAsync(buffer);
stream.Position = 0;
var buffer2 = new byte[200];
var read2 = await stream.ReadAsync(buffer2);
Assert.Equal(100, read1);
Assert.Equal(100, read2);
Assert.Equal(data.AsMemory(0, read1).ToArray(), buffer);
Assert.Equal(data.AsMemory(0, read2).ToArray(), buffer2.AsMemory(0, read2).ToArray());
}
public async Task FileBufferingReadStream_AsyncReadUnderThreshold_DoesntCreateFile()
{
var inner = MakeStream(1024 * 2);
using (var stream = new FileBufferingReadStream(inner, 1024 * 3, null, Directory.GetCurrentDirectory()))
{
var bytes = new byte[1000];
var read0 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(bytes.Length, read0);
Assert.Equal(read0, stream.Length);
Assert.Equal(read0, stream.Position);
Assert.True(stream.InMemory);
Assert.Null(stream.TempFileName);
var read1 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(bytes.Length, read1);
Assert.Equal(read0 + read1, stream.Length);
Assert.Equal(read0 + read1, stream.Position);
Assert.True(stream.InMemory);
Assert.Null(stream.TempFileName);
var read2 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(inner.Length - read0 - read1, read2);
Assert.Equal(read0 + read1 + read2, stream.Length);
Assert.Equal(read0 + read1 + read2, stream.Position);
Assert.True(stream.InMemory);
Assert.Null(stream.TempFileName);
var read3 = await stream.ReadAsync(bytes, 0, bytes.Length);
Assert.Equal(0, read3);
}
}
public async Task ReadAsyncThenCopyToAsyncWorks()
{
var data = Enumerable.Range(0, 1024).Select(b => (byte)b).ToArray();
var inner = new MemoryStream(data);
using var stream = new FileBufferingReadStream(inner, 1024 * 1024, bufferLimit: null, GetCurrentDirectory());
var withoutBufferMs = new MemoryStream();
var buffer = new byte[100];
await stream.ReadAsync(buffer);
await stream.CopyToAsync(withoutBufferMs);
Assert.Equal(data.AsMemory(0, 100).ToArray(), buffer);
Assert.Equal(data.AsMemory(100).ToArray(), withoutBufferMs.ToArray());
}
