public void TestOperations()
{
var stream = CreateStream("ABCDE");
var sub = new Substream(stream, 1, 3);
// invalid operations
AssertException(() => sub.Seek(0, (SeekOrigin)(Int32)42));
AssertException(() => sub.Write(new Byte[10], 0, 10));
// seek
sub.Position = 0;
for (var i = 0; i < sub.Length; i++)
{
sub.Seek(i, SeekOrigin.Begin);
Assert.AreEqual(stream.Position, 1 + i);
}
sub.Position = 0;
for (var i = 0; i < sub.Length; i++)
{
sub.Seek(-i, SeekOrigin.End);
Assert.AreEqual(stream.Position, 4 - i);
}
sub.Position = 0;
for (var i = 0; i < sub.Length; i++)
{
sub.Seek(1, SeekOrigin.Current);
Assert.AreEqual(stream.Position, 2 + i);
}
for (var i = 0; i < sub.Length; i++)
{
sub.Seek(-1, SeekOrigin.Current);
Assert.AreEqual(stream.Position, 3 - i);
}
sub.Position = 0;
sub.Seek(3, SeekOrigin.Current);
Assert.AreEqual(stream.Position, 4);
sub.Seek(-3, SeekOrigin.Current);
Assert.AreEqual(stream.Position, 1);
// read
sub.Position = 0;
Assert.AreEqual(ReadChar(sub), 'B');
Assert.AreEqual(sub.Position, 1);
Assert.AreEqual(ReadChar(sub), 'C');
Assert.AreEqual(sub.Position, 2);
Assert.AreEqual(ReadChar(sub), 'D');
Assert.AreEqual(sub.Position, 3);
Assert.AreEqual(ReadChar(sub), 0);
sub.Position = 0;
Assert.AreEqual(ReadString(sub), "BCD");
Assert.AreEqual(ReadString(sub), "");
sub.Position = 1;
Assert.AreEqual(ReadString(sub), "CD");
Assert.AreEqual(ReadString(sub), "");
sub.Position = 2;
Assert.AreEqual(ReadString(sub), "D");
Assert.AreEqual(ReadString(sub), "");
sub.Position = 3;
Assert.AreEqual(ReadString(sub), "");
}
public void TestProperties()
{
// stream flags
Assert.IsTrue(new Substream(CreateStream(""), 0, 0).CanSeek);
Assert.IsTrue(new Substream(CreateStream(""), 0, 0).CanRead);
Assert.IsFalse(new Substream(CreateStream(""), 0, 0).CanWrite);
// stream position
Assert.AreEqual(new Substream(CreateStream(""), 0, 0).Position, 0);
Assert.AreEqual(new Substream(CreateStream("A"), 0, 1).Position, 0);
Assert.AreEqual(new Substream(CreateStream("A"), 1, 0).Position, 0);
Assert.AreEqual(new Substream(CreateStream("ABC"), 0, 3).Position, 0);
Assert.AreEqual(new Substream(CreateStream("ABC"), 1, 2).Position, 0);
Assert.AreEqual(new Substream(CreateStream("ABC"), 2, 1).Position, 0);
Assert.AreEqual(new Substream(CreateStream("ABC"), 3, 0).Position, 0);
using (var stream = CreateStream("ABCDE"))
using (var sub = new Substream(stream, 1, 3))
{
for (var i = 0; i < 7; i++)
{
sub.Position = i;
Assert.AreEqual(sub.Position, i);
Assert.AreEqual(stream.Position, i + 1);
}
}
// stream length
AssertException(() => new Substream(CreateStream("ABC"), 0, 3).SetLength(2));
Assert.AreEqual(new Substream(CreateStream(""), 0, 0).Length, 0);
Assert.AreEqual(new Substream(CreateStream("A"), 0, 1).Length, 1);
Assert.AreEqual(new Substream(CreateStream("A"), 1, 0).Length, 0);
Assert.AreEqual(new Substream(CreateStream("ABC"), 0, 3).Length, 3);
Assert.AreEqual(new Substream(CreateStream("ABC"), 0, 2).Length, 2);
Assert.AreEqual(new Substream(CreateStream("ABC"), 0, 1).Length, 1);
Assert.AreEqual(new Substream(CreateStream("ABC"), 1, 2).Length, 2);
Assert.AreEqual(new Substream(CreateStream("ABC"), 1, 1).Length, 1);
Assert.AreEqual(new Substream(CreateStream("ABC"), 2, 1).Length, 1);
Assert.AreEqual(new Substream(CreateStream("ABC"), 3, 0).Length, 0);
}