public void PromptsForPool()
        {
            using (TestHostContext hc = CreateTestContext())
            {
                // Arrange.
                var command = new CommandSettings(hc, args: new string[0]);
                _promptManager
                    .Setup(x => x.ReadValue(
                        Constants.Agent.CommandLine.Args.Pool, // argName
                        StringUtil.Loc("AgentMachinePoolNameLabel"), // description
                        false, // secret
                        "default", // defaultValue
                        Validators.NonEmptyValidator, // validator
                        false)) // unattended
                    .Returns("some pool");

                // Act.
                string actual = command.GetPool();

                // Assert.
                Assert.Equal("some pool", actual);
            }
        }