public void IfCanSeekIsFalseLengthAndPositionShouldNotBeCalled()
{
var baseStream = new DelegateStream(
canReadFunc: () => true,
canSeekFunc: () => false,
readFunc: (buffer, offset, count) => 0);
var trackingStream = new CallTrackingStream(baseStream);
var dest = Stream.Null;
trackingStream.CopyTo(dest);
Assert.InRange(trackingStream.TimesCalled(nameof(trackingStream.CanSeek)), 0, 1);
Assert.Equal(0, trackingStream.TimesCalled(nameof(trackingStream.Length)));
Assert.Equal(0, trackingStream.TimesCalled(nameof(trackingStream.Position)));
// We can't override CopyTo since it's not virtual, so checking TimesCalled
// for CopyTo will result in 0. Instead, we check that Read was called,
// and validate the parameters passed there.
Assert.Equal(1, trackingStream.TimesCalled(nameof(trackingStream.Read)));
byte[] outerBuffer = trackingStream.ReadBuffer;
int outerOffset = trackingStream.ReadOffset;
int outerCount = trackingStream.ReadCount;
Assert.NotNull(outerBuffer);
Assert.InRange(outerOffset, 0, outerBuffer.Length - outerCount);
Assert.InRange(outerCount, 1, int.MaxValue); // the buffer can't be size 0
}
public void IfLengthMinusPositionPositiveOverflowsBufferSizeShouldStillBePositive(long length, long position)
{
// The new implementation of Stream.CopyTo calculates the bytes left
// in the Stream by calling Length - Position. This can overflow to a
// negative number, so this tests that if that happens we don't send
// in a negative bufferSize.
var baseStream = new DelegateStream(
canReadFunc: () => true,
canSeekFunc: () => true,
lengthFunc: () => length,
positionGetFunc: () => position,
readFunc: (buffer, offset, count) => 0);
var trackingStream = new CallTrackingStream(baseStream);
var dest = Stream.Null;
trackingStream.CopyTo(dest);
// CopyTo is not virtual, so we can't override it in
// CallTrackingStream and record the arguments directly.
// Instead, validate the arguments passed to Read.
Assert.Equal(1, trackingStream.TimesCalled(nameof(trackingStream.Read)));
byte[] outerBuffer = trackingStream.ReadBuffer;
int outerOffset = trackingStream.ReadOffset;
int outerCount = trackingStream.ReadCount;
Assert.NotNull(outerBuffer);
Assert.InRange(outerOffset, 0, outerBuffer.Length - outerCount);
Assert.InRange(outerCount, 1, int.MaxValue);
}
public void IfLengthIsLessThanOrEqualToPositionCopyToShouldStillBeCalledWithAPositiveBufferSize(long length, long position)
{
// Streams with their Lengths <= their Positions, e.g.
// new MemoryStream { Position = 3 }.SetLength(1)
// should still be called CopyTo{Async} on with a
// bufferSize of at least 1.
var baseStream = new DelegateStream(
canReadFunc: () => true,
canSeekFunc: () => true,
lengthFunc: () => length,
positionGetFunc: () => position,
readFunc: (buffer, offset, count) => 0);
var trackingStream = new CallTrackingStream(baseStream);
var dest = Stream.Null;
trackingStream.CopyTo(dest);
// CopyTo is not virtual, so we can't override it in
// CallTrackingStream and record the arguments directly.
// Instead, validate the arguments passed to Read.
Assert.Equal(1, trackingStream.TimesCalled(nameof(trackingStream.Read)));
byte[] outerBuffer = trackingStream.ReadBuffer;
int outerOffset = trackingStream.ReadOffset;
int outerCount = trackingStream.ReadCount;
Assert.NotNull(outerBuffer);
Assert.InRange(outerOffset, 0, outerBuffer.Length - outerCount);
Assert.InRange(outerCount, 1, int.MaxValue);
}
public void IfCanSeekIsTrueLengthAndPositionShouldOnlyBeCalledOnce()
{
var baseStream = new DelegateStream(
canReadFunc: () => true,
canSeekFunc: () => true,
readFunc: (buffer, offset, count) => 0,
lengthFunc: () => 0L,
positionGetFunc: () => 0L);
var trackingStream = new CallTrackingStream(baseStream);
var dest = Stream.Null;
trackingStream.CopyTo(dest);
Assert.InRange(trackingStream.TimesCalled(nameof(trackingStream.Length)), 0, 1);
Assert.InRange(trackingStream.TimesCalled(nameof(trackingStream.Position)), 0, 1);
}
public void IfLengthIsGreaterThanPositionAndDoesNotOverflowEverythingShouldGoNormally(long length, long position)
{
const int ReadLimit = 7;
// Lambda state
byte[] outerBuffer = null;
int? outerOffset = null;
int? outerCount = null;
int readsLeft = ReadLimit;
var srcBase = new DelegateStream(
canReadFunc: () => true,
canSeekFunc: () => true,
lengthFunc: () => length,
positionGetFunc: () => position,
readFunc: (buffer, offset, count) =>
{
Assert.NotNull(buffer);
Assert.InRange(offset, 0, buffer.Length - count);
Assert.InRange(count, 1, int.MaxValue);
// CopyTo should always pass in the same buffer/offset/count
if (outerBuffer != null)
{
Assert.Same(outerBuffer, buffer);
}
else
{
outerBuffer = buffer;
}
if (outerOffset != null)
{
Assert.Equal(outerOffset, offset);
}
else
{
outerOffset = offset;
}
if (outerCount != null)
{
Assert.Equal(outerCount, count);
}
else
{
outerCount = count;
}
return(--readsLeft); // CopyTo will call Read on this ReadLimit times before stopping
});
var src = new CallTrackingStream(srcBase);
var destBase = new DelegateStream(
canWriteFunc: () => true,
writeFunc: (buffer, offset, count) =>
{
Assert.Same(outerBuffer, buffer);
Assert.Equal(outerOffset, offset);
Assert.Equal(readsLeft, count);
});
var dest = new CallTrackingStream(destBase);
src.CopyTo(dest);
Assert.Equal(ReadLimit, src.TimesCalled(nameof(src.Read)));
Assert.Equal(ReadLimit - 1, dest.TimesCalled(nameof(dest.Write)));
}