// check length and position (position will be in the truncated space. without a write, this leaves thile file trunaceted)
public static void TestStreamWrite_SetLengthTruncate()
{
DebugStream stm = StmInit("0123456789");
stm.SetLength(5);
Assert.AreEqual(10, stm.Position);
Assert.AreEqual(5, stm.Length);
byte[] rgbExpected = Encoding.UTF8.GetBytes("01234");
byte[] rgbRead = new byte[5];
// try to read from beyond the end
Assert.AreEqual(0, stm.Read(rgbRead, 0, 5));
//now reposition and read
stm.Position = 0;
Assert.AreEqual(5, stm.Read(rgbRead, 0, 5));
Assert.AreEqual(rgbExpected, rgbRead);
}
public static void TestStreamSetLength_SeekIntoSpace_WriteIntoSpaceNoGrow()
{
DebugStream stm = new DebugStream();
stm.SetLength(20);
stm.Position = 10;
Assert.AreEqual(10, stm.Position);
Assert.AreEqual(20, stm.Length);
byte[] rgbWrite = new byte[2] {
65, 66
};
stm.Write(rgbWrite, 0, 2);
Assert.AreEqual(12, stm.Position);
Assert.AreEqual(20, stm.Length);
stm.Position = 10;
byte[] rgbRead = new byte[2];
Assert.AreEqual(2, stm.Read(rgbRead, 0, 2));
Assert.AreEqual(rgbWrite, rgbRead);
}
public static void TestStreamSetLength_SeekIntoSpace_WriteIntoSpaceGrow()
{
DebugStream stm = new DebugStream();
stm.SetLength(20);
stm.Position = 18;
Assert.AreEqual(18, stm.Position);
Assert.AreEqual(20, stm.Length);
byte[] rgbWrite = new byte[6] {
65, 66, 67, 68, 69, 70
};
stm.Write(rgbWrite, 0, 6);
Assert.AreEqual(24, stm.Position);
Assert.AreEqual(24, stm.Length);
stm.Position = 18;
byte[] rgbRead = new byte[6];
Assert.AreEqual(6, stm.Read(rgbRead, 0, 6));
Assert.AreEqual(rgbWrite, rgbRead);
}
public static void TestStreamWrite_SetLengthTruncate_Write()
{
DebugStream stm = StmInit("0123456789");
stm.SetLength(5);
Assert.AreEqual(10, stm.Position);
Assert.AreEqual(5, stm.Length);
byte[] rgbWrite = new byte[2] {
65, 66
};
stm.Write(rgbWrite, 0, 2);
Assert.AreEqual(12, stm.Position);
Assert.AreEqual(12, stm.Length);
stm.Position = 0;
byte[] rgbRead = new byte[12];
Assert.AreEqual(12, stm.Read(rgbRead, 0, 12));
byte[] rgbExpected = new byte[] { 48, 49, 50, 51, 52, 0, 0, 0, 0, 0, 65, 66 };
Assert.AreEqual(rgbExpected, rgbRead);
}
public static void TestStreamWrite_SetLengthGrowFile() // check length and position
{
DebugStream stm = StmInit("0123456789");
stm.SetLength(20);
Assert.AreEqual(10, stm.Position);
Assert.AreEqual(20, stm.Length);
stm.Seek(-4, SeekOrigin.Current);
byte[] rgbWrite = new byte[2] {
65, 66
};
stm.Write(rgbWrite, 0, 2);
Assert.AreEqual(8, stm.Position);
Assert.AreEqual(20, stm.Length);
stm.Position = 0;
byte[] rgbExpected = Encoding.UTF8.GetBytes("012345AB89");
byte[] rgbRead = new byte[10];
Assert.AreEqual(10, stm.Read(rgbRead, 0, 10));
Assert.AreEqual(rgbExpected, rgbRead);
}