Module: Asciidoctor::Revealjs::Converter::Helpers

Defined in:
lib/asciidoctor-revealjs/converter.rb

Overview

This module gets mixed in to every node (the context of the template) at the time the node is being converted. The properties and methods in this module effectively become direct members of the template.

Constant Summary collapse

EOL = 
%(\n)
SliceHintRx = 
/  +/
DEFAULT_TOCLEVELS =

Defaults

2
DEFAULT_SECTNUMLEVELS = 
3
VOID_ELEMENTS = 
%w(area base br col command embed hr img input keygen link
meta param source track wbr)
STEM_EQNUMS_AMS = 
'ams'
STEM_EQNUMS_NONE = 
'none'
STEM_EQNUMS_VALID_VALUES = 
[
  STEM_EQNUMS_NONE,
  STEM_EQNUMS_AMS,
  'all'
]
MATHJAX_VERSION = 
'3.2.0'
@@slide_footnotes =

Display footnotes per slide

{}
@@section_footnotes = 
{}

Instance Method Summary collapse

Instance Method Details

Copied from asciidoctor/lib/asciidoctor/converter/html5.rb (method is private)



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# File 'lib/asciidoctor-revealjs/converter.rb', line 374

def append_link_constraint_attrs node, attrs = []
  rel = 'nofollow' if node.option? 'nofollow'
  if (window = node.attributes['window'])
    attrs << %( target="#{window}")
    attrs << (rel ? %( rel="#{rel} noopener") : ' rel="noopener"') if window == '_blank' || (node.option? 'noopener')
  elsif rel
    attrs << %( rel="#{rel}")
  end
  attrs
end

#bool_data_attr(val) ⇒ Object

bool_data_attr If the AsciiDoc attribute doesn’t exist, no HTML attribute is added If the AsciiDoc attribute exist and is a true value, HTML attribute is enabled (bool) If the AsciiDoc attribute exist and is a false value, HTML attribute is a false string Ex: a feature is enabled globally but can be disabled using a data- attribute on individual items :revealjs_previewlinks: True then :example.com[Link text, preview=false] Here the template must have data-preview-link=“false” not just no data-preview-link attribute



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# File 'lib/asciidoctor-revealjs/converter.rb', line 44

def bool_data_attr val
  return false unless attr?(val)
  if attr(val).downcase == 'false' || attr(val) == '0'
    'false'
  else
    true
  end
end

#clear_slide_footnotes ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 177

def clear_slide_footnotes
  @@slide_footnotes = {}
end

#content_for(key, opts = {}, &block) ⇒ Object

Capture nested template content and register it with the specified key, to be executed at a later time.

This method must be invoked using the control code directive (i.e., -). By using a control code directive, the block is set up to append the result directly to the output buffer. (Integrations often hide the distinction between a control code directive and an output directive in this context).

key - The Symbol under which to save the template block. opts - A Hash of options to control processing (default: {}):

* :append  - A Boolean that indicates whether to append this block
             to others registered with this key (default: false).
* :content - String content to be used if template content is not
             provided (optional).

block - The template content (in Slim template syntax).

Examples

- content_for :body
  p content
- content_for :body, append: true
  p more content

Returns nothing.



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# File 'lib/asciidoctor-revealjs/converter.rb', line 335

def content_for key, opts = {}, &block
  @content = {} unless defined? @content
  (opts[:append] ? (@content[key] ||= []) : (@content[key] = [])) << (block_given? ? block : lambda { opts[:content] })
  nil
end

#content_for?(key) ⇒ Boolean

Checks whether deferred template content has been registered for the specified key.

key - The Symbol under which to look for saved template blocks.

Returns a Boolean indicating whether content has been registered for this key.

Returns:

  • (Boolean) 


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# File 'lib/asciidoctor-revealjs/converter.rb', line 346

def content_for? key
  (defined? @content) && (@content.key? key)
end

#convert_image(node = self) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 241

def convert_image(node = self)
  # When the stretch class is present, block images will take the most space
  # they can take. Setting width and height can override that.
  # We pinned the 100% to height to avoid aspect ratio breakage and since
  # widescreen monitors are the most popular, chances are that height will
  # be the biggest constraint
  if node.has_role?('stretch') && !(node.attr?(:width) || node.attr?(:height))
    height_value = "100%"
  elsif node.attr? 'height'
    height_value = node.attr 'height'
  else
    height_value = nil
  end
  html_attrs = (node.attr? 'width') ? %( width="#{node.attr 'width'}") : ''
  html_attrs = %(#{html_attrs} height="#{height_value}") if height_value
  html_attrs = %(#{html_attrs} title="#{node.attr 'title'}") if node.attr? 'title'
  html_attrs = %(#{html_attrs} style="background: #{node.attr :background}") if node.attr? 'background'
  img, src = img_tag(node, node.attr('target'), html_attrs)
  img_link(node, src, img)
end

#convert_inline_image(node = self) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 211

def convert_inline_image(node = self)
  target = node.target
  if (node.type || 'image') == 'icon'
    if (icons = node.document.attr 'icons') == 'font'
      i_class_attr_val = %(#{node.attr(:set, 'fa')} fa-#{target})
      i_class_attr_val = %(#{i_class_attr_val} fa-#{node.attr 'size'}) if node.attr? 'size'
      if node.attr? 'flip'
        i_class_attr_val = %(#{i_class_attr_val} fa-flip-#{node.attr 'flip'})
      elsif node.attr? 'rotate'
        i_class_attr_val = %(#{i_class_attr_val} fa-rotate-#{node.attr 'rotate'})
      end
      attrs = (node.attr? 'title') ? %( title="#{node.attr 'title'}") : ''
      img = %(<i class="#{i_class_attr_val}"#{attrs}></i>)
    elsif icons
      attrs = (node.attr? 'width') ? %( width="#{node.attr 'width'}") : ''
      attrs = %(#{attrs} height="#{node.attr 'height'}") if node.attr? 'height'
      attrs = %(#{attrs} title="#{node.attr 'title'}") if node.attr? 'title'
      img = %(<img src="#{src = node.icon_uri target}" alt="#{encode_attribute_value node.alt}"#{attrs}>)
    else
      img = %([#{node.alt}&#93;)
    end
  else
    html_attrs = (node.attr? 'width') ? %( width="#{node.attr 'width'}") : ''
    html_attrs = %(#{html_attrs} height="#{node.attr 'height'}") if node.attr? 'height'
    html_attrs = %(#{html_attrs} title="#{node.attr 'title'}") if node.attr? 'title'
    img, src = img_tag(node, target, html_attrs)
  end
  img_link(node, src, img)
end

#data_attrs(attributes) ⇒ Hash

Extracts data- attributes from the attributes.

Parameters:

  • attributes (Hash) —

    (default: {})

Returns:

  • (Hash) —

    a Hash that contains only data- attributes



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# File 'lib/asciidoctor-revealjs/converter.rb', line 106

def data_attrs(attributes)
  # key can be an Integer (for positional attributes)
  attributes.map { |key, value| (key == 'step') ? ['data-fragment-index', value] : [key, value] }
            .to_h
            .select { |key, _| key.to_s.start_with?('data-') }
end

#encode_attribute_value(val) ⇒ Object

Copied from asciidoctor/lib/asciidoctor/converter/html5.rb (method is private)



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# File 'lib/asciidoctor-revealjs/converter.rb', line 386

def encode_attribute_value val
  (val.include? '"') ? (val.gsub '"', '&quot;') : val
end

#format_author(node, author) ⇒ Object

TODO:

remove this code when the new converter becomes available in the main gem

Copied from asciidoctor/lib/asciidoctor/converter/semantic-html5.rb which is not yet shipped



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# File 'lib/asciidoctor-revealjs/converter.rb', line 411

def format_author node, author
  in_context 'author' do
    %(<span class="author">#{node.sub_replacements author.name}#{author.email ? %( #{node.sub_macros author.email}) : ''}</span>)
  end
end

#generate_authors(node) ⇒ Object

TODO:

remove this code when the new converter becomes available in the main gem

Copied from asciidoctor/lib/asciidoctor/converter/semantic-html5.rb which is not yet shipped



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# File 'lib/asciidoctor-revealjs/converter.rb', line 392

def generate_authors node
  return if node.authors.empty?

  if node.authors.length == 1
    %(<p class="byline">
  #{format_author node, node.authors.first}
  </p>)
  else
    result = ['<ul class="byline">']
    node.authors.each do |author|
      result << "<li>#{format_author node, author}</li>"
    end
    result << '</ul>'
    result.join Asciidoctor::LF
  end
end

#generate_stem(cdn_base) ⇒ String

Generate the Mathjax markup to process STEM expressions

Parameters:

  • cdn_base (String)

Returns:

  • (String) 


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# File 'lib/asciidoctor-revealjs/converter.rb', line 439

def generate_stem(cdn_base)
  if attr?(:stem)
    eqnums_val = attr('eqnums', STEM_EQNUMS_NONE).downcase
    unless STEM_EQNUMS_VALID_VALUES.include?(eqnums_val)
      eqnums_val = STEM_EQNUMS_AMS
    end
    mathjax_configuration = {
      tex: {
        inlineMath: [Asciidoctor::INLINE_MATH_DELIMITERS[:latexmath]],
        displayMath: [Asciidoctor::BLOCK_MATH_DELIMITERS[:latexmath]],
        processEscapes: false,
        tags: eqnums_val,
      },
      options: {
        ignoreHtmlClass: 'nostem|nolatexmath'
      },
      asciimath: {
        delimiters: [Asciidoctor::BLOCK_MATH_DELIMITERS[:asciimath]],
      },
      loader: {
        load: ['input/asciimath', 'output/chtml', 'ui/menu']
      }
    }
    mathjaxdir = attr('mathjaxdir', "#{cdn_base}/mathjax/#{MATHJAX_VERSION}/es5")
    %(<script>window.MathJax = #{JSON.generate(mathjax_configuration)};</script>) +
    %(<script async src="#{mathjaxdir}/tex-mml-chtml.js"></script>)
  end
end

#html5_converter ⇒ Object

Retrieves the built-in html5 converter.

Returns the instance of the Asciidoctor::Converter::Html5Converter associated with this node.



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# File 'lib/asciidoctor-revealjs/converter.rb', line 207

def html5_converter
  converter.instance_variable_get("@delegate_converter")
end

#html_tag(name, attributes = {}, content = nil) { ... } ⇒ String

Creates an HTML tag with the given name and optionally attributes. Can take a block that will run between the opening and closing tags.

Parameters:

  • name (#to_s) —

    the name of the tag.

  • attributes (Hash) (defaults to: {}) —

    (default: {})

  • content (#to_s) (defaults to: nil) —

    the content; nil to call the block. (default: nil).

Yields:

  • The block of Slim/HTML code within the tag (optional).

Returns:

  • (String) —

    a rendered HTML element.



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# File 'lib/asciidoctor-revealjs/converter.rb', line 84

def html_tag(name, attributes = {}, content = nil)
  attrs = attributes.inject([]) do |attrs, (k, v)|
    next attrs unless v && (v == true || !v.nil_or_empty?)
    v = v.compact.join(' ') if v.is_a? Array
    attrs << (v == true ? k : %(#{k}="#{v}"))
  end
  attrs_str = attrs.empty? ? '' : ' ' + attrs.join(' ')

  if VOID_ELEMENTS.include? name.to_s
    %(<#{name}#{attrs_str}>)
  else
    content ||= (yield if block_given?)
    %(<#{name}#{attrs_str}>#{content}</#{name}>)
  end
end

#img_link(node = self, src, content) ⇒ Object

Wrap the <img> element in a <a> element if the link attribute is defined



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# File 'lib/asciidoctor-revealjs/converter.rb', line 280

def img_link(node = self, src, content)
  if (node.attr? 'link') && ((href_attr_val = node.attr 'link') != 'self' || (href_attr_val = src))
    if (link_preview_value = bool_data_attr :link_preview)
      data_preview_attr = %( data-preview-link="#{link_preview_value == true ? "" : link_preview_value}")
    end
    return %(<a class="image" href="#{href_attr_val}"#{(append_link_constraint_attrs node).join}#{data_preview_attr}>#{content}</a>)
  end

  content
end

#img_tag(node = self, target, html_attrs) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 262

def img_tag(node = self, target, html_attrs)
  if ((node.attr? 'format', 'svg') || (target.include? '.svg')) && node.document.safe < ::Asciidoctor::SafeMode::SECURE
    if node.option? 'inline'
      img = (html5_converter.read_svg_contents node, target) || %(<span class="alt">#{node.alt}</span>)
    elsif node.option? 'interactive'
      fallback = (node.attr? 'fallback') ? %(<img src="#{node.image_uri node.attr 'fallback'}" alt="#{encode_attribute_value node.alt}"#{html_attrs}>) : %(<span class="alt">#{node.alt}</span>)
      img = %(<object type="image/svg+xml" data="#{src = node.image_uri target}"#{html_attrs}>#{fallback}</object>)
    else
      img = %(<img src="#{src = node.image_uri target}" alt="#{encode_attribute_value node.alt}"#{html_attrs}>)
    end
  else
    img = %(<img src="#{src = node.image_uri target}" alt="#{encode_attribute_value node.alt}"#{html_attrs}>)
  end

  [img, src]
end

#in_context(name) ⇒ Object

TODO:

remove this code when the new converter becomes available in the main gem

Copied from asciidoctor/lib/asciidoctor/converter/semantic-html5.rb which is not yet shipped



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# File 'lib/asciidoctor-revealjs/converter.rb', line 419

def in_context name
  (@convert_context ||= []).push name
  result = yield
  @convert_context.pop
  result
end

#inline_text_container(content = nil) ⇒ String

Wrap an inline text in a <span> element if the node contains a role, an id or data- attributes.

Parameters:

  • content (#to_s) (defaults to: nil) —

    the content; nil to call the block. (default: nil).

Returns:

  • (String) —

    the content or the content wrapped in a <span> element as string



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# File 'lib/asciidoctor-revealjs/converter.rb', line 119

def inline_text_container(content = nil)
  data_attrs = data_attrs(@attributes)
  classes = [role, ('fragment' if (option? :step) || (attr? 'step') || (roles.include? 'step'))].compact
  if !roles.empty? || !data_attrs.empty? || !@id.nil?
    html_tag('span', { :id => @id, :class => classes }.merge(data_attrs), (content || (yield if block_given?)))
  else
    content || (yield if block_given?)
  end
end

#resolve_content ⇒ Object

Between delimiters (–) is code taken from asciidoctor-bespoke 1.0.0.alpha.1 Licensed under MIT, Copyright © 2015-2016 Dan Allen and the Asciidoctor Project – Retrieve the converted content, wrap it in a ‘<p>` element if the content_model equals :simple and return the result.

Returns the block content as a String, wrapped inside a ‘<p>` element if the content_model equals `:simple`.



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# File 'lib/asciidoctor-revealjs/converter.rb', line 307

def resolve_content
  @content_model == :simple ? %(<p>#{content}</p>) : content
end

#revealjs_dependencies(document, node, revealjsdir) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 291

def revealjs_dependencies(document, node, revealjsdir)
  dependencies = []
  dependencies << "{ src: '#{revealjsdir}/plugin/zoom/zoom.js', async: true, callback: function () { Reveal.registerPlugin(RevealZoom) } }" unless (node.attr? 'revealjs_plugin_zoom', 'disabled')
  dependencies << "{ src: '#{revealjsdir}/plugin/notes/notes.js', async: true, callback: function () { Reveal.registerPlugin(RevealNotes) } }" unless (node.attr? 'revealjs_plugin_notes', 'disabled')
  dependencies << "{ src: '#{revealjsdir}/plugin/search/search.js', async: true, callback: function () { Reveal.registerPlugin(RevealSearch) } }" if (node.attr? 'revealjs_plugin_search', 'enabled')
  dependencies.join(",\n      ")
end

#section_level(sec = self) ⇒ Integer

Returns corrected section level.

Parameters:

  • sec (Asciidoctor::Section) (defaults to: self) —

    the section node (default: self).

Returns:

  • (Integer) 


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# File 'lib/asciidoctor-revealjs/converter.rb', line 136

def section_level(sec = self)
  @_section_level ||= (sec.level == 0 && sec.special) ? 1 : sec.level
end

#section_title(sec = self) ⇒ String

Returns the captioned section’s title, optionally numbered.

Parameters:

  • sec (Asciidoctor::Section) (defaults to: self) —

    the section node (default: self).

Returns:

  • (String) 


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# File 'lib/asciidoctor-revealjs/converter.rb', line 193

def section_title(sec = self)
  sectnumlevels = document.attr(:sectnumlevels, DEFAULT_SECTNUMLEVELS).to_i

  if sec.numbered && !sec.caption && sec.level <= sectnumlevels
    [sec.sectnum, sec.captioned_title].join(' ')
  else
    sec.captioned_title
  end
end

#slice_text(str, active = nil) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 24

def slice_text str, active = nil
  if (active || (active.nil? && (option? :slice))) && (str.include? '  ')
    (str.split SliceHintRx).map {|line| %(<span class="line">#{line}</span>) }.join EOL
  else
    str
  end
end

#slide_footnote(footnote) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 146

def slide_footnote(footnote)
  footnote_parent = footnote.parent
  # footnotes declared on the section title are processed during the parsing/substitution.
  # as a result, we need to store them to display them on the right slide/section
  if footnote_parent.instance_of?(::Asciidoctor::Section)
    footnote_parent_object_id = footnote_parent.object_id
    section_footnotes = (@@section_footnotes[footnote_parent_object_id] || [])
    footnote_index = section_footnotes.length + 1
    attributes = footnote.attributes.merge({ 'index' => footnote_index })
    inline_footnote = Asciidoctor::Inline.new(footnote_parent, footnote.context, footnote.text, :attributes => attributes)
    section_footnotes << Asciidoctor::Document::Footnote.new(inline_footnote.attr(:index), inline_footnote.id, inline_footnote.text)
    @@section_footnotes[footnote_parent_object_id] = section_footnotes
    inline_footnote
  else
    parent = footnote.parent
    until parent == nil || parent.instance_of?(::Asciidoctor::Section)
      parent = parent.parent
    end
    # check if there is any footnote attached on the section title
    section_footnotes = parent != nil ? @@section_footnotes[parent.object_id] || [] : []
    initial_index = footnote.attr(:index)
    # reset the footnote numbering to 1 on each slide
    # make sure that if a footnote is used more than once it will use the same index/number
    slide_index = (existing_footnote = @@slide_footnotes[initial_index]) ? existing_footnote.index : @@slide_footnotes.length + section_footnotes.length + 1
    attributes = footnote.attributes.merge({ 'index' => slide_index })
    inline_footnote = Asciidoctor::Inline.new(footnote_parent, footnote.context, footnote.text, :attributes => attributes)
    @@slide_footnotes[initial_index] = Asciidoctor::Document::Footnote.new(inline_footnote.attr(:index), inline_footnote.id, inline_footnote.text)
    inline_footnote
  end
end

#slide_footnotes(section) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 181

def slide_footnotes(section)
  section_object_id = section.object_id
  section_footnotes = @@section_footnotes[section_object_id] || []
  section_footnotes + @@slide_footnotes.values
end

#to_boolean(val) ⇒ Object 



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# File 'lib/asciidoctor-revealjs/converter.rb', line 32

def to_boolean val
  val && val != 'false' && val.to_s != '0' || false
end

#to_valid_slidenumber(val) ⇒ Object

false needs to be verbatim everything else is a string. Calling side isn’t responsible for quoting so we are doing it here



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# File 'lib/asciidoctor-revealjs/converter.rb', line 55

def to_valid_slidenumber val
  # corner case: empty is empty attribute which is true
  return true if val == ""
  # using to_s here handles both the 'false' string and the false boolean
  val.to_s == 'false' ? false : "'#{val}'"
end

#yield_content(key, opts = {}) ⇒ Object

Evaluates the deferred template content registered with the specified key.

When the corresponding content_for method is invoked using a control code directive, the block is set up to append the result to the output buffer directly.

key - The Symbol under which to look for template blocks to yield. opts - A Hash of options to control processing (default: {}):

* :drain - A Boolean indicating whether to drain the key of blocks
           after calling them (default: true).

Examples

- yield_content :body

Returns nothing (assuming the content has been captured in the context of control code).



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# File 'lib/asciidoctor-revealjs/converter.rb', line 366

def yield_content key, opts = {}
  if (defined? @content) && (blks = (opts.fetch :drain, true) ? (@content.delete key) : @content[key])
    blks.map {|b| b.call }.join
  end
  nil
end