public void Gzip_CompressDecompress()
{
// Start with a MemoryStream created from the sample data
using (MemoryStream source = new MemoryStream(s_sampledata))
{
using (MemoryStream dest = new MemoryStream())
{
// Compress the data into the destination memory stream instance
using (GzipWriter compressor = new GzipWriter(dest, CompressionLevel.Optimal, true)) source.CopyTo(compressor);
// The compressed data should be smaller than the source data
Assert.IsTrue(dest.Length < source.Length);
source.SetLength(0); // Clear the source stream
dest.Position = 0; // Reset the destination stream
// Decompress the data back into the source memory stream
using (GzipReader decompressor = new GzipReader(dest, true)) decompressor.CopyTo(source);
// Ensure that the original data has been restored
Assert.AreEqual(source.Length, s_sampledata.Length);
Assert.IsTrue(s_sampledata.SequenceEqual(source.ToArray()));
}
}
}
public void Gzip_DecompressExternal()
{
// Decompress a stream created externally to this library
using (GzipReader reader = new GzipReader(Assembly.GetExecutingAssembly().GetManifestResourceStream("zuki.io.compression.test.thethreemusketeers.gz")))
{
using (MemoryStream dest = new MemoryStream())
{
reader.CopyTo(dest);
dest.Flush();
// Verify that the output matches the sample data byte-for-byte
Assert.IsTrue(Enumerable.SequenceEqual(s_sampledata, dest.ToArray()));
}
}
}
public void Gzip_Position()
{
// Start with a MemoryStream created from the sample data
using (MemoryStream source = new MemoryStream(s_sampledata))
{
using (MemoryStream dest = new MemoryStream())
{
// Test a compression stream
using (GzipWriter compressor = new GzipWriter(dest, CompressionLevel.Optimal, true))
{
// The stream should report position zero prior to compression
Assert.AreEqual(0L, compressor.Position);
source.CopyTo(compressor);
// The stream should report non-zero after compression
Assert.AreNotEqual(0L, compressor.Position);
// Attempting to set the position on the stream should throw
try { compressor.Position = 12345L; Assert.Fail("Property should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
source.SetLength(0); // Clear the source stream
dest.Position = 0; // Reset the destination stream
// Test a decompression stream
using (GzipReader decompressor = new GzipReader(dest, true))
{
// The stream should report position zero prior to compression
Assert.AreEqual(0L, decompressor.Position);
decompressor.CopyTo(source);
// The stream should report non-zero after compression
Assert.AreNotEqual(0L, decompressor.Position);
// Attempting to set the position on the stream should throw
try { decompressor.Position = 12345L; Assert.Fail("Property should have thrown an exception"); }
catch (Exception ex) { Assert.IsInstanceOfType(ex, typeof(NotSupportedException)); }
}
}
}
}
