Global Custom Match

[Anthony Dewhirst]

Is there anyway to set a custom match to be used across all Moq

Or even set a custom IEquator so that we can implement .Equals in a custom way?

I have objects that I want to test using value equality but in the non test code they should use this.

Hope that this makes sense.

[Anthony Dewhirst]

I have come up with a solution for the moment that works for me. It needs expanding and possibly some more checking, but it generally gives you an answer.

here is the code:

    public static class MoqExtensions
    {
        private static IEqualityComparer _equalityComparer;

        public static void SetEqualityComparer(IEqualityComparer equalityComparer)
        {
            _equalityComparer = equalityComparer;
        }

        public static ISetup<T> ValueSetup<T>(this Mock<T> mock, Expression<Action<T>> expression)
            where T : class
        {
            var updatedExpression = (Expression<Action<T>>)new MyExpressionVisitor().Visit(expression);
            return mock.Setup(updatedExpression);
        }

        public static T Match<T>(this T instance)
        {
            return It.Is<T>(t => _equalityComparer.Equals(instance, t));
        }

        private class MyExpressionVisitor : ExpressionVisitor
        {
            protected override Expression VisitMember(MemberExpression node)
            {
                if(node.Expression.NodeType == ExpressionType.Constant)
                {
                    // We have to do this to get access to the base value and not the wrapped value
                    var param = Expression.Constant(Expression.Lambda(node).Compile().DynamicInvoke());
                    var call = Expression.Call(typeof(MoqExtensions), "Match", new[] { node.Type }, param);

                    return call;
                }

                return base.VisitMember(node);
            }
        }
    }