rename Liquid 4 has_key to key to add compatibility for liquid 4

[marcanuy]

Using Liquid 4 key.

[DirtyF]

It did fix the error message that prevented Jekyll 3.5 from compiling

[benbalter]

Based on the failing tests, we may need to see if context responds to key? and if not use has_key? to maintain compatibility with pre 3.5.

[marcanuy]

What about this? Having each code for both versions:

          if Gem.loaded_specs['liquid'].version < Gem::Version.create('4.0')
            if context.has_key?(gist_id)
              gist_id = context[gist_id]
            end
            if context.has_key?(filename)
              filename = context[filename]
            end
          else
            if context.key?(gist_id)
              gist_id = context[gist_id]
            end
            if context.key?(filename)
              filename = context[filename]
            end
          end

Until there is another more elegant solution.

[parkr]

What about a helper method?

          
            if context_contains_key?(context, gist_id)
              gist_id = context[gist_id]
            end

            if context_contains_key?(context, filename)
              filename = context[filename]
            end
      
# ...

def context_contains_key?(context, key)
  if context.respond_to?(:has_key?)
    context.has_key?(key)
  else
    context.key?(key)
  end
end

[DirtyF]

@benbalter you're right without a helper it is not backward compatible

Liquid Exception: undefined method key?' for #<Liquid::Context:0x007fe5abf97cf0> in /Users/frank/code/jamstatic.fr/_posts/2016-09-18-utiliser-des-plugins-jekyll-avec-github-pages.md jekyll 3.4.3 | Error: undefined method key?' for #Liquid::Context:0x007fe5abf97cf0

[DirtyF]

Works fine on 3.4.3 and 3.5.0
Do this plugin still want to support Jekyll 2.0?

[parkr]

Do this plugin still want to support Jekyll 2.0?

Jekyll 2.0 is old enough that I would say no, we don't need support for it.

[parkr]

@jekyllbot: merge