moq SetupSequence with queue only executing first time-CodePudding

I am trying to make a mock dynamically with a loop that returns values based on a queue. The code used is as follows(Got it from another answer on stackoverflow).

var numberQueue = new Queue<int>(new[] { 4, 8, 16, 43});
var mock = new Mock<ITest>();
mock.SetupSequence(x => x.GetNumber()).Returns(numberQueue.Dequeue);

int x1 = mock.Object.GetNumber(); // expected: 4 actual: 4 
int x2 = mock.Object.GetNumber(); // expected: 8 actual: 0
int x3 = mock.Object.GetNumber(); // expected: 16 actual: 0
int x4 = mock.Object.GetNumber(); // expected: 32 actual: 0

x1.Should().Be(4); // passes
x2.Should().Be(8); // fails
x3.Should().Be(16); // fails
x4.Should().Be(32); //fails

The first one works fine but after that everything is 0. I am trying to get it running in this way because I want to be able to dynamically setup a mock for an IDataReader.

CodePudding user response：

There are multiple ways to fix your problem, let me show you the three most basic ones.

Option #1

Use Setup instead of SetupSequence

mock.Setup(x => x.GetNumber())
    .Returns(numberQueue.Dequeue);

After this change your test will fail at the x4.Should().Be(32) line because x4 is 43.

Option #2

Use SetupSequence with multiple Returns calls

mock.SetupSequence(x => x.GetNumber())
    .Returns(numberQueue.Dequeue)
    .Returns(numberQueue.Dequeue)
    .Returns(numberQueue.Dequeue)
    .Returns(numberQueue.Dequeue);

Option #3

mock.SetupSequence(x => x.GetNumber())
    .Returns(4)
    .Returns(8)
    .Returns(16)
    .Returns(43);