lambda helpers only receive options if used with arguments #599
Description
If my template contains {{#foo something}}...{{/foo}} and the value of foo in the current context is a function, it will be called with arguments ["something", options]. However, if the helper is used without arguments ({{#foo}}...{{/foo}}), the function will be called without arguments. It should be called with a single options argument.
Use case: I'm implementing a multi-conditional helper (swtich-when-otherwise) where switch and when will require a single argument, and otherwise will be used without an argument. In the otherwise helper, I need to access options.data to determine if any of the when clauses have matched, and options.fn to render the otherwise block if not.