public void Lz4Legacy_Flush()
{
// Verify behavior of flushing a compression stream
using (MemoryStream compressed = new MemoryStream())
{
using (Lz4LegacyWriter stream = new Lz4LegacyWriter(compressed, true))
{
stream.Write(s_sampledata, 0, s_sampledata.Length);
// Get the unflushed length of the compressed stream and flush it
long unflushed = compressed.Length;
stream.Flush();
// The expectation is that the output stream will be longer after the flush
long flushedonce = compressed.Length;
Assert.IsTrue(compressed.Length > unflushed);
// Flushing the same data a second time should not have any impact at all
stream.Flush();
Assert.AreEqual(compressed.Length, flushedonce);
// The stream should still be writable after a flush operation
stream.Write(s_sampledata, 0, s_sampledata.Length / 10);
}
}
// Verify behavior of flushing a decompression stream
using (Lz4LegacyReader stream = new Lz4LegacyReader(new MemoryStream(s_sampledata)))
{
// Flush has no effect on decompression streams, just ensure it doesn't throw
stream.Flush();
}
}
public void Lz4Legacy_Read()
{
byte[] buffer = new byte[8192]; // 8KiB data buffer
using (MemoryStream compressed = new MemoryStream())
{
// Start with a compressed MemoryStream created from the sample data
using (Lz4LegacyWriter compressor = new Lz4LegacyWriter(compressed, CompressionLevel.Optimal, true))
{
try { compressor.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
compressor.Write(s_sampledata, 0, s_sampledata.Length);
compressor.Flush();
}
// Check the constructor for ArgumentNullException while we're here
try { using (Lz4LegacyReader decompressor = new Lz4LegacyReader(null, false)) { }; Assert.Fail("Constructor should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
// Create a decompressor to test some of the error cases
using (Lz4LegacyReader decompressor = new Lz4LegacyReader(compressed, true))
{
// Send in some bum arguments to Read() to check they are caught
try { decompressor.Read(null, 0, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
try { decompressor.Read(buffer, -1, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { decompressor.Read(buffer, 0, -1); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { decompressor.Read(buffer, 0, buffer.Length + 1024); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentException)); }
// Attempting to read from the end of the compressed stream should throw an InvalidDataException
try { decompressor.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(InvalidDataException)); }
// Attempting to read from the middle of the compressed stream should throw an InvalidDataException
compressed.Position = compressed.Position / 2;
try { decompressor.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(InvalidDataException)); }
}
// Create a new decompressor against the same stream and make sure it doesn't throw
compressed.Position = 0;
using (Lz4LegacyReader decompressor = new Lz4LegacyReader(compressed, true))
{
// Reading zero bytes should not throw an exception
decompressor.Read(buffer, 0, 0);
while (decompressor.Read(buffer, 0, 8192) != 0)
{
}
}
}
}
public void Lz4Legacy_CompressExternal()
{
// This method generates an output file that can be tested externally; "thethreemusketeers.txt" is
// set to Copy Always to the output directory, it can be diffed after running the external tool
using (Lz4LegacyWriter writer = new Lz4LegacyWriter(File.Create(Path.Combine(Environment.CurrentDirectory, "thethreemusketeers.lz4-legacy"))))
{
writer.Write(s_sampledata);
writer.Flush();
}
}
public void Lz4Legacy_Write()
{
byte[] buffer = new byte[8192]; // 8KiB data buffer
// Compress the sample data using a call to Write directly
using (MemoryStream compressed = new MemoryStream())
{
// Check the constructor for ArgumentNullException while we're here
try { using (Lz4LegacyWriter compressor = new Lz4LegacyWriter(null)) { }; Assert.Fail("Constructor should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
using (Lz4LegacyWriter compressor = new Lz4LegacyWriter(compressed, CompressionLevel.Optimal, true))
{
// Send in some bum arguments to Write() to check they are caught
try { compressor.Write(null); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
try { compressor.Write(null, 0, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentNullException)); }
try { compressor.Write(s_sampledata, -1, 0); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { compressor.Write(s_sampledata, 0, -1); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
try { compressor.Write(s_sampledata, 0, s_sampledata.Length + 1024); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentException)); }
// Not writing anything shouldn't throw an exception
compressor.Write(s_sampledata, 0, 0);
// Compress the data; there really isn't much that can go wrong with Write() itself
compressor.Write(s_sampledata, 0, s_sampledata.Length);
compressor.Flush();
}
using (Lz4LegacyReader reader = new Lz4LegacyReader(compressed, true))
{
try { reader.Write(buffer, 0, buffer.Length); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
}
}
public void Lz4Legacy_CompressionLevel()
{
using (MemoryStream source = new MemoryStream(s_sampledata))
{
long fastest, optimal; // Size of compressed streams
// CompressionLevel.NoCompression is not valid
try { using (Lz4LegacyWriter stream = new Lz4LegacyWriter(source, CompressionLevel.NoCompression)) Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ArgumentOutOfRangeException)); }
// Compress using CompressionLevel.Fastest
using (MemoryStream compressed = new MemoryStream())
{
using (Lz4LegacyWriter compressor = new Lz4LegacyWriter(compressed, CompressionLevel.Fastest))
{
compressor.Write(s_sampledata, 0, s_sampledata.Length);
compressor.Flush();
fastest = compressed.Length;
}
}
// Compress using CompressionLevel.Optimal
using (MemoryStream compressed = new MemoryStream())
{
using (Lz4LegacyWriter compressor = new Lz4LegacyWriter(compressed, CompressionLevel.Optimal))
{
compressor.Write(s_sampledata, 0, s_sampledata.Length);
compressor.Flush();
optimal = compressed.Length;
}
}
// Optimal compression should result in a smaller output stream than fastest
// and fastest should result in a smaller output stream than uncompressed
Assert.IsTrue(optimal < fastest);
Assert.IsTrue(fastest < source.Length);
}
}
public void Lz4Legacy_WriterDispose()
{
byte[] buffer = new byte[8192]; // 8KiB data buffer
// Create a dummy stream and immediately dispose of it
Lz4LegacyWriter stream = new Lz4LegacyWriter(new MemoryStream(s_sampledata), CompressionLevel.Optimal);
stream.Dispose();
// Test double dispose
stream.Dispose();
// All properties and methods should throw an ObjectDisposedException
try { var bs = stream.BaseStream; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var b = stream.CanRead; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var b = stream.CanSeek; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var b = stream.CanWrite; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Flush(); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var l = stream.Length; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { var l = stream.Position; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Position = 12345L; Assert.Fail("Property access should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Read(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Seek(0, SeekOrigin.Current); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.SetLength(12345L); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Write(buffer); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
try { stream.Write(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
// Ensure that an underlying stream is disposed of properly if leaveopen is not set
MemoryStream ms = new MemoryStream(s_sampledata);
using (Lz4LegacyWriter compressor = new Lz4LegacyWriter(ms, CompressionLevel.Fastest)) { }
try { ms.Write(buffer, 0, 8192); Assert.Fail("Method call should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(ObjectDisposedException)); }
// Ensure that an underlying stream is not disposed of if leaveopen is set
ms = new MemoryStream(s_sampledata);
using (Lz4LegacyWriter compressor = new Lz4LegacyWriter(ms, CompressionLevel.Fastest, true)) { }
ms.Write(buffer, 0, 8192);
ms.Dispose();
}