Middleman: undefined method `link_to' when rendering markdown from data file

问题

I am using Markdown written in data file to render HTML in HAML template with Middleman static page generator.

My data file, data/faq.yaml looks like this:

dog:
  question: I want to know more about a dog.
  answerA: (HTML in data) Just <a href="https://google.com">Google</a> it!
  answerB: (Markdown link in data) Just [Google](https://google.com) it!

To convert this markdown to HTML, I am using custom helper defined in config.rb:

helpers do
    def markdown(text)
        Tilt['markdown'].new { text }.render
    end
end

Which then I use in my HAML template like this:

= markdown(data.faq.dog.answerA)

Everything works perfectly until I try to render markdown link written in data file.

Below is my faq.haml template with:

• Markdown link written directly in HAML, which renders through HAML's markdown filter
• Reference to answerA from data with HTML link written directly
• Reference to answerB from data with same link written with markdown syntax

faq.haml:

.answer
    :markdown
        (HAML) Just [Google](https://google.com) it!
    = markdown(data.faq.dog.answerA)
    = markdown(data.faq.dog.answerB)

First 2 links render propely, but markdown link in answerB throws following error:

undefined method `link_to' for #<Object:0x000000044f9e18>

Traceback:

/home/myself/.rvm/gems/ruby-2.4.0/gems/middleman-core-4.2.1/lib/middleman-core/renderers/kramdown.rb: in convert_a
    48.     scope.link_to(content, link, attr)  

Why is Kramdown unable to convert a markdown link when "asked" to do so via custom helper which references data file, but does it properly when same syntax is used directly in HAML? What can be done, so that markdown link in = markdown(data.faq.dog.answerB) renders properly?

Ps. My end goal will be to reference links which are already defined in separate data file, but I think that solving this issue first is necessary in order to achieve that goal.

回答1:

App context needs to passed to Tilt.

def markdown(text)
  Tilt['markdown'].new(context: @app) { text }.render
end

Source

来源：https://stackoverflow.com/questions/44240111/middleman-undefined-method-link-to-when-rendering-markdown-from-data-file