public void HasExactType()
        {
            var opt = new TypingTestExpressionOptimizer();

            foreach (var e in new Expression[]
            {
                Expression.Constant(42),
                Expression.Default(typeof(int)),

                Expression.NewArrayBounds(typeof(int), Expression.Constant(1)),
                Expression.NewArrayInit(typeof(int), Expression.Constant(1)),

                Expression.New(typeof(string).GetConstructor(new[] { typeof(char), typeof(int) }), Expression.Constant('*'), Expression.Constant(1)),
                Expression.ListInit(Expression.New(typeof(List <int>).GetConstructor(Type.EmptyTypes)), Expression.ElementInit(typeof(List <int>).GetMethod(nameof(List <int> .Add), new[] { typeof(int) }), Expression.Constant(1))),
                Expression.MemberInit(Expression.New(typeof(StrongBox <int>).GetConstructor(Type.EmptyTypes)), Expression.Bind(typeof(StrongBox <int>).GetField(nameof(StrongBox <int> .Value)), Expression.Constant(1))),

                Expression.IsFalse(Expression.Constant(true)),
                Expression.IsTrue(Expression.Constant(true)),

                Expression.TypeEqual(Expression.Constant(42), typeof(int)),
                Expression.TypeIs(Expression.Constant(42), typeof(int)),

                Expression.Call(Expression.Constant(""), typeof(string).GetMethod(nameof(string.ToUpper), Type.EmptyTypes)),

                Expression.Convert(Expression.Default(typeof(object)), typeof(int)),
            })
            {
                Assert.IsTrue(opt.HasExactType(e), e.ToString());
            }

            foreach (var e in new Expression[]
            {
                Expression.Constant(null),
                Expression.Constant("", typeof(object)),

                Expression.Default(typeof(int?)),
                Expression.Default(typeof(string)),

                Expression.Convert(Expression.Default(typeof(string)), typeof(object)),
                Expression.Convert(Expression.Default(typeof(object)), typeof(int?)),
            })
            {
                Assert.IsFalse(opt.HasExactType(e), e.ToString());
            }
        }