public void ReplaceFirst()
        {
            var input = new StringValue("abcabc");

            var arguments = new FilterArguments().Add(new StringValue("b")).Add(new StringValue("B"));
            var context   = new TemplateContext();

            var result = StringFilters.ReplaceFirst(input, arguments, context);

            Assert.Equal("aBcabc", result.ToStringValue());
        }