public void AggregateEnvironmentVariablesTest()
        {
            var         launcher = new Launcher();
            LaunchGroup group    =
                new LaunchGroup(null,
                                new[]
            {
                new LaunchGroup(null,
                                null,
                                new[]
                {
                    launcher
                }),
            });

            group.EnvironmentVariables.UpdateWith(
                new EnvironmentVariable("A", "A"),
                new EnvironmentVariable("B", "B"),
                new EnvironmentVariable("D", "D"));

            group.Groups[0].EnvironmentVariables.UpdateWith(
                new EnvironmentVariable("C", "C"),
                new EnvironmentVariable("B", "B2"));

            launcher.EnvironmentVariables.UpdateWith(
                new EnvironmentVariable("D", "D2"),
                new EnvironmentVariable("E", "E"));

            var envVars = launcher.AggregateEnvironmentVariables();

            Assert.That(envVars, Contains.Item(new EnvironmentVariable("A", "A")));
            Assert.That(envVars, Contains.Item(new EnvironmentVariable("B", "B2")));
            Assert.That(envVars, Contains.Item(new EnvironmentVariable("C", "C")));
            Assert.That(envVars, Contains.Item(new EnvironmentVariable("D", "D2")));
            Assert.That(envVars, Contains.Item(new EnvironmentVariable("E", "E")));
        }