public void CompressAndDecompressShouldBeAssociativeOperations()
{
// Given
var compressor = new GZipDataCompressor();
var originalData = new MemoryStream(new byte[] { 1, 2, 3 });
// When
var compressSource1 = originalData;
var compressDestination1 = new MemoryStream();
compressor.Compress(compressSource1, compressDestination1);
var decompressSource1 = compressDestination1;
var decompressDestination1 = new MemoryStream();
compressor.Decompress(decompressSource1, decompressDestination1);
var compressSource2 = decompressDestination1;
var compressDestination2 = new MemoryStream();
compressor.Compress(compressSource2, compressDestination2);
var decompressSource2 = compressDestination2;
var decompressDestination2 = new MemoryStream();
compressor.Decompress(decompressSource2, decompressDestination2);
// Then
CollectionAssert.AreEquivalent(originalData.ToArray(), decompressDestination1.ToArray());
CollectionAssert.AreEquivalent(originalData.ToArray(), decompressDestination2.ToArray());
CollectionAssert.AreEquivalent(compressDestination1.ToArray(), compressDestination2.ToArray());
}
public void GZipCompressorTest(int len)
{
var compressor = new GZipDataCompressor();
var str = new string('a', len);
var bytes = Encoding.UTF8.GetBytes(str);
var compressedBytes = compressor.Compress(bytes);
var decompressedBytes = compressor.Decompress(compressedBytes);
var text = Encoding.UTF8.GetString(decompressedBytes);
Assert.Equal(str, text);
}
public void DecompressPerformanceTest(long size, int iterations)
{
// Given
var compressor = new GZipDataCompressor();
var stopwatch = new Stopwatch();
var compressSource = new byte[size];
new Random(DateTime.Now.Millisecond).NextBytes(compressSource);
var compressSourceStream = new MemoryStream(compressSource);
var decompressSourceStream = new MemoryStream();
compressor.Compress(compressSourceStream, decompressSourceStream);
// When
compressor.Decompress(new MemoryStream(), new MemoryStream()); // JIT
for (var i = 0; i < iterations; ++i)
{
using (var decompressResultStream = new MemoryStream())
{
stopwatch.Start();
compressor.Decompress(decompressSourceStream, decompressResultStream);
stopwatch.Stop();
}
}
// Then
Console.WriteLine("Size: {0:N0} Kb", size / 1024.0);
Console.WriteLine("Iterations: {0} times", iterations);
Console.WriteLine("Compress speed: {0:N4} Kbytes/sec", (size * iterations / 1024.0) / stopwatch.Elapsed.TotalSeconds);
}
public void DecompressShouldNotCloseSourceStream()
{
// Given
var source = new MemoryStream();
var compressor = new GZipDataCompressor();
// When
TestDelegate decompressSourceStreamTwice
= () =>
{
var destination1 = new MemoryStream();
compressor.Decompress(source, destination1);
var destination2 = new MemoryStream();
compressor.Decompress(source, destination2);
};
// Then
Assert.DoesNotThrow(decompressSourceStreamTwice);
}
public void DecompressResultShouldBeImmutable()
{
// Given
var source = new MemoryStream();
var compressor = new GZipDataCompressor();
// When
compressor.Compress(new MemoryStream(new byte[] { 1, 2, 3 }), source);
source.Position = 0;
var destination1 = new MemoryStream();
compressor.Decompress(source, destination1);
var destination2 = new MemoryStream();
compressor.Decompress(source, destination2);
// Then
CollectionAssert.AreEquivalent(destination1.ToArray(), destination2.ToArray());
}
public void CanDecompressEmptyStream()
{
// Given
var source = new MemoryStream();
var compressor = new GZipDataCompressor();
// When
var destination = new MemoryStream();
TestDelegate decompressEmptyStream
= () => compressor.Decompress(source, destination);
// Then
Assert.DoesNotThrow(decompressEmptyStream);
Assert.AreEqual(0, destination.Length);
}
public void DecompressMemoryTest(long size, int iterations)
{
// Given
var compressor = new GZipDataCompressor();
var compressSource = new byte[size];
new Random(DateTime.Now.Millisecond).NextBytes(compressSource);
var compressSourceStream = new MemoryStream(compressSource);
var decompressSourceStream = new MemoryStream();
compressor.Compress(compressSourceStream, decompressSourceStream);
// When
var memoryBefore = GC.GetTotalMemory(true);
for (var i = 0; i < iterations; ++i)
{
using (var decompressResultStream = new MemoryStream())
{
compressor.Decompress(decompressSourceStream, decompressResultStream);
}
}
GC.Collect();
GC.WaitForPendingFinalizers();
var memoryAfter = GC.GetTotalMemory(true);
// Then
var memoryLeak = memoryAfter - memoryBefore;
var memeryLeakFactor = (double)memoryLeak / size;
Console.WriteLine(@"Size: {0:N0} Kb", size / 1024.0);
Console.WriteLine(@"Iterations: {0} times", iterations);
Console.WriteLine(@"Memory leak: {0:N4} Kb", memoryLeak / 1024.0);
Console.WriteLine(@"Memory leak factor: {0:N4}", memeryLeakFactor);
Assert.Less(memeryLeakFactor, 2.5);
}
public void DecompressShouldNotCloseDestinationStream()
{
// Given
var source = new MemoryStream();
var compressor = new GZipDataCompressor();
// When
compressor.Compress(new MemoryStream(new byte[] { 1, 2, 3 }), source);
source.Position = 0;
var destination = new MemoryStream();
compressor.Decompress(source, destination);
// Then
Assert.IsTrue(destination.CanSeek);
Assert.IsTrue(destination.CanRead);
Assert.IsTrue(destination.CanWrite);
}