public void PerformWriteOpOnReadOnlyWrapper()
{
byte[] buf = new byte[10];
using (FileStreamWrapper fsw = new FileStreamWrapper())
{
// If:
// ... I have a readonly file stream wrapper
// Then:
// ... Attempting to perform any write operation should result in an exception
Assert.Throws <InvalidOperationException>(() => fsw.WriteData(buf, 1));
Assert.Throws <InvalidOperationException>(() => fsw.Flush());
}
}
public void PerformOpWithoutInit()
{
byte[] buf = new byte[10];
using (FileStreamWrapper fsw = new FileStreamWrapper())
{
// If:
// ... I have a file stream wrapper that hasn't been initialized
// Then:
// ... Attempting to perform any operation will result in an exception
Assert.Throws <InvalidOperationException>(() => fsw.ReadData(buf, 1));
Assert.Throws <InvalidOperationException>(() => fsw.ReadData(buf, 1, 0));
Assert.Throws <InvalidOperationException>(() => fsw.WriteData(buf, 1));
Assert.Throws <InvalidOperationException>(() => fsw.Flush());
}
}
[InlineData(10)] // Internal buffer too small, forces a flush
public void WriteData(int internalBufferLength)
{
string fileName = Path.GetTempFileName();
byte[] bytesToWrite = Encoding.Unicode.GetBytes("hello");
try
{
// If:
// ... I have a file stream that has been initialized
// ... And I write some bytes to it
using (FileStreamWrapper fsw = new FileStreamWrapper())
{
fsw.Init(fileName, internalBufferLength, FileAccess.ReadWrite);
int bytesWritten = fsw.WriteData(bytesToWrite, bytesToWrite.Length);
Assert.Equal(bytesToWrite.Length, bytesWritten);
}
// Then:
// ... The file I wrote to should contain only the bytes I wrote out
using (FileStream fs = File.OpenRead(fileName))
{
byte[] readBackBytes = new byte[1024];
int bytesRead = fs.Read(readBackBytes, 0, readBackBytes.Length);
Assert.Equal(bytesToWrite.Length, bytesRead); // If bytes read is not equal, then more or less of the original string was written to the file
Assert.True(bytesToWrite.SequenceEqual(readBackBytes.Take(bytesRead)));
}
}
finally
{
// Cleanup:
// ... Delete the test file
CleanupTestFile(fileName);
}
}