public void WithWrites_ExpandsBufferWhenNeeded()
{
// Arrange
var origBuffer = new byte[15];
var offset = 6;
origBuffer[0] = 123; // So we can check it was retained during expansion
// Act/Assert
using (var stream = new MessagePackBinaryBlockStream(origBuffer, offset))
{
// We can fit the 6-byte offset plus 5-byte header plus 3 written bytes
// into the original 15-byte buffer
stream.Write(new byte[] { 10, 20, 30 }, 0, 3);
Assert.Same(origBuffer, stream.Buffer);
// Trying to add two more exceeds the capacity, so the buffer expands
stream.Write(new byte[] { 40, 50 }, 0, 2);
Assert.NotSame(origBuffer, stream.Buffer);
Assert.True(stream.Buffer.Length > origBuffer.Length);
// Check the expanded buffer has the expected contents
stream.Close();
Assert.Equal(123, stream.Buffer[0]); // Retains other values from original buffer
Assert.Equal(MessagePackCode.Bin32, stream.Buffer[offset]);
Assert.Equal(5, ReadBigEndianInt32(stream.Buffer, offset + 1));
Assert.Equal(10, stream.Buffer[offset + 5]);
Assert.Equal(20, stream.Buffer[offset + 6]);
Assert.Equal(30, stream.Buffer[offset + 7]);
Assert.Equal(40, stream.Buffer[offset + 8]);
Assert.Equal(50, stream.Buffer[offset + 9]);
}
}
public void LengthIncludesHeaderButPositionDoesNot()
{
// Arrange
var buffer = new byte[20];
var offset = 3;
// Act/Assert
using (var stream = new MessagePackBinaryBlockStream(buffer, offset))
{
stream.Write(new byte[] { 0x01, 0x02 }, 0, 2);
Assert.Equal(7, stream.Length);
Assert.Equal(2, stream.Position);
}
}
public void WithWrites_WritesToUnderlyingBuffer()
{
// Arrange
var buffer = new byte[100];
var offset = 58; // Arbitrary
// Act/Assert
using (var stream = new MessagePackBinaryBlockStream(buffer, offset))
{
stream.Write(new byte[] { 10, 20, 30, 40 }, 1, 2); // Write 2 bytes
stream.Write(new byte[] { 101 }, 0, 1); // Write another 1 byte
stream.Close();
Assert.Equal(MessagePackCode.Bin32, buffer[offset]);
Assert.Equal(3, ReadBigEndianInt32(buffer, offset + 1));
Assert.Equal(20, buffer[offset + 5]);
Assert.Equal(30, buffer[offset + 6]);
Assert.Equal(101, buffer[offset + 7]);
}
}
