Change arrangement

[anton-yashin]

Hi!

LightMock can't change arrangements? Like this:

    public class ArrangementTests
    {
    //...
        [Fact]
        public void Arrange_ChangeReturnValue()
        {
            var mockContext = new MockContext<IFoo>();
            var fooMock = new FooMock(mockContext);

            mockContext.Arrange(f => f.Execute()).Returns("1");
            Assert.Equal("1", fooMock.Execute());

            mockContext.Arrange(f => f.Execute()).Returns("2");
            Assert.Equal("2", fooMock.Execute());
        }

        [Fact]
        public void Arrange_ChangeCallback()
        {
            int firstResult = 0;
            int secondResult = 0;
            var mockContext = new MockContext<IFoo>();
            var fooMock = new FooMock(mockContext);

            mockContext.Arrange(f => f.Execute(The<int>.IsAnyValue)).Callback<int>(i => firstResult = i);
            fooMock.Execute(1);
            mockContext.Arrange(f => f.Execute(The<int>.IsAnyValue)).Callback<int>(i => secondResult = i);
            fooMock.Execute(2);

            Assert.Equal(1, firstResult);
            Assert.Equal(2, secondResult);
        }

        [Fact]
        public void Arrange_ChangeException()
        {
            var mockContext = new MockContext<IFoo>();
            var fooMock = new FooMock(mockContext);

            mockContext.Arrange(f => f.Execute(The<int>.IsAnyValue)).Throws<System.ArgumentNullException>();
            Assert.Throws<System.ArgumentNullException>(() => fooMock.Execute(1));

            mockContext.Arrange(f => f.Execute(The<int>.IsAnyValue)).Throws<System.ArgumentOutOfRangeException>();
            Assert.Throws<System.ArgumentOutOfRangeException>(() => fooMock.Execute(1));
        }

        [Fact]
        public void Arrange_SimulatousReturnAndCallback()
        {
            string firstResult = "";
            var mockContext = new MockContext<IFoo>();
            var fooMock = new FooMock(mockContext);

            mockContext.Arrange(f => f.Execute(The<string>.IsAnyValue)).Returns("hi");
            mockContext.Arrange(f => f.Execute(The<string>.IsAnyValue)).Callback<string>(i => firstResult = i);

            var result = fooMock.Execute("hello");

            Assert.Equal("hi", result);
            Assert.Equal("hello", firstResult);
        }
    }

Tests abowe do not pass. Is this behavior intended? Can it be changed? I can write a pull request that changes this behavior.

Thanks.

[anton-yashin]

Thanks!