public void DirectoryExists()
{
Assert.ThrowsExact <ArgumentNullException>(() => Assert.DirectoryExists(null as string));
Assert.ThrowsExact <ArgumentNullException>(() => Assert.DirectoryExists(null as DirectoryInfo));
Assert.ThrowsExact <AssertionException>(() => Assert.DirectoryExists(NonExistingDirectory));
Assert.ThrowsExact <AssertionException>(() => Assert.DirectoryExists(NonExistingDirectoryInfo));
Assert.ThrowsExact <AssertionException>(() => Assert.DirectoryExists(new DirectoryInfo(NonExistingDirectory)));
Assert.DoesNotThrow(() => Assert.DirectoryExists(ExistingDirectory));
Assert.DoesNotThrow(() => Assert.DirectoryExists(ExistingDirectoryInfo));
}