class Sass::Tree::Visitors::ToCss

A visitor for converting a Sass tree into CSS.

Constants

NEWLINE

Avoid allocating lots of new strings for `#output`. This is important because `#output` is called all the time.

Attributes

source_mapping[R]

The source mapping for the generated CSS file. This is only set if `build_source_mapping` is passed to the constructor and {Sass::Engine#render} has been run.

Public Class Methods

new(build_source_mapping = false) click to toggle source

@param build_source_mapping [Boolean] Whether to build a

\{Sass::Source::Map} while creating the CSS output. The mapping will
be available from \{#source\_mapping} after the visitor has completed.
# File lib/sass/tree/visitors/to_css.rb, line 11
def initialize(build_source_mapping = false)
  @tabs = 0
  @line = 1
  @offset = 1
  @result = ""
  @source_mapping = Sass::Source::Map.new if build_source_mapping
end

Public Instance Methods

visit(node) click to toggle source

Runs the visitor on `node`.

@param node [Sass::Tree::Node] The root node of the tree to convert to CSS> @return [String] The CSS output.

Calls superclass method Sass::Tree::Visitors::Base.visit
# File lib/sass/tree/visitors/to_css.rb, line 23
def visit(node)
  super
rescue Sass::SyntaxError => e
  e.modify_backtrace(:filename => node.filename, :line => node.line)
  raise e
end

Protected Instance Methods

ends_with?(str) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 54
def ends_with?(str)
  @result.end_with?(str)
end
erase!(chars) click to toggle source

Move the output cursor back `chars` characters.

# File lib/sass/tree/visitors/to_css.rb, line 59
def erase!(chars)
  return if chars == 0
  str = @result.slice!(-chars..-1)
  newlines = str.count("\n")
  if newlines > 0
    @line -= newlines
    @offset = @result[@result.rindex("\n") || 0..-1].size
  else
    @offset -= chars
  end
end
for_node(node, attr_prefix = nil) { || ... } click to toggle source

Associate all output produced in a block with a given node. Used for source mapping.

# File lib/sass/tree/visitors/to_css.rb, line 41
def for_node(node, attr_prefix = nil)
  return yield unless @source_mapping
  start_pos = Sass::Source::Position.new(@line, @offset)
  yield

  range_attr = attr_prefix ? :"#{attr_prefix}_source_range" : :source_range
  return if node.invisible? || !node.send(range_attr)
  source_range = node.send(range_attr)
  target_end_pos = Sass::Source::Position.new(@line, @offset)
  target_range = Sass::Source::Range.new(start_pos, target_end_pos, nil)
  @source_mapping.add(source_range, target_range)
end
lstrip() { || ... } click to toggle source

lstrip the first output in the given block.

# File lib/sass/tree/visitors/to_css.rb, line 100
def lstrip
  old_lstrip = @lstrip
  @lstrip = true
  yield
ensure
  @lstrip = @lstrip && old_lstrip
end
output(s) click to toggle source

Add `s` to the output string and update the line and offset information accordingly.

# File lib/sass/tree/visitors/to_css.rb, line 77
def output(s)
  if @lstrip
    s = s.gsub(/\A\s+/, "")
    @lstrip = false
  end

  newlines = s.count(NEWLINE)
  if newlines > 0
    @line += newlines
    @offset = s[s.rindex(NEWLINE)..-1].size
  else
    @offset += s.size
  end

  @result << s
end
prepend!(prefix) click to toggle source

Prepend `prefix` to the output string.

# File lib/sass/tree/visitors/to_css.rb, line 109
def prepend!(prefix)
  @result.insert 0, prefix
  return unless @source_mapping

  line_delta = prefix.count("\n")
  offset_delta = prefix.gsub(/.*\n/, '').size
  @source_mapping.shift_output_offsets(offset_delta)
  @source_mapping.shift_output_lines(line_delta)
end
rstrip!() click to toggle source

Strip all trailing whitespace from the output string.

# File lib/sass/tree/visitors/to_css.rb, line 95
def rstrip!
  erase! @result.length - 1 - (@result.rindex(/[^\s]/) || -1)
end
visit_charset(node) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 155
def visit_charset(node)
  for_node(node) {output("@charset \"#{node.name}\";")}
end
visit_comment(node) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 159
def visit_comment(node)
  return if node.invisible?
  spaces = ('  ' * [@tabs - node.resolved_value[/^ */].size, 0].max)
  output(spaces)

  content = node.resolved_value.split("\n").join("\n" + spaces)
  if node.type == :silent
    content.gsub!(%r{^(\s*)//(.*)$}) {|md| "#{$1}/*#{$2} */"}
  end
  if (node.style == :compact || node.style == :compressed) && node.type != :loud
    content.gsub!(/\n +(\* *(?!\/))?/, ' ')
  end
  for_node(node) {output(content)}
end
visit_cssimport(node) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 259
def visit_cssimport(node)
  visit_directive(node)
end
visit_directive(node) click to toggle source

@comment

rubocop:disable MethodLength
# File lib/sass/tree/visitors/to_css.rb, line 176
def visit_directive(node)
  was_in_directive = @in_directive
  tab_str = '  ' * @tabs
  if !node.has_children || node.children.empty?
    output(tab_str)
    for_node(node) {output(node.resolved_value)}
    if node.has_children
      output("#{' ' unless node.style == :compressed}{}")
    elsif node.children.empty?
      output(";")
    end
    return
  end

  @in_directive = @in_directive || !node.is_a?(Sass::Tree::MediaNode)
  output(tab_str) if node.style != :compressed
  for_node(node) {output(node.resolved_value)}
  output(node.style == :compressed ? "{" : " {")
  output(node.style == :compact ? ' ' : "\n") if node.style != :compressed

  had_children = true
  first = true
  node.children.each do |child|
    next if child.invisible?
    if node.style == :compact
      if child.is_a?(Sass::Tree::PropNode)
        with_tabs(first || !had_children ? 0 : @tabs + 1) do
          visit(child)
          output(' ')
        end
      else
        unless had_children
          erase! 1
          output "\n"
        end

        if first
          lstrip {with_tabs(@tabs + 1) {visit(child)}}
        else
          with_tabs(@tabs + 1) {visit(child)}
        end

        rstrip!
        output "\n"
      end
      had_children = child.has_children
      first = false
    elsif node.style == :compressed
      unless had_children
        output(";") unless ends_with?(";")
      end
      with_tabs(0) {visit(child)}
      had_children = child.has_children
    else
      with_tabs(@tabs + 1) {visit(child)}
      output "\n"
    end
  end
  rstrip!
  if node.style == :compressed && ends_with?(";")
    erase! 1
  end
  if node.style == :expanded
    output("\n#{tab_str}")
  elsif node.style != :compressed
    output(" ")
  end
  output("}")
ensure
  @in_directive = was_in_directive
end
visit_keyframerule(node) click to toggle source

@comment

rubocop:enable MethodLength
# File lib/sass/tree/visitors/to_css.rb, line 378
def visit_keyframerule(node)
  visit_directive(node)
end
visit_media(node) click to toggle source

@comment

rubocop:enable MethodLength
# File lib/sass/tree/visitors/to_css.rb, line 250
def visit_media(node)
  with_tabs(@tabs + node.tabs) {visit_directive(node)}
  output("\n") if node.style != :compressed && node.group_end
end
visit_prop(node) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 263
def visit_prop(node)
  return if node.resolved_value.empty?
  tab_str = '  ' * (@tabs + node.tabs)
  output(tab_str)
  for_node(node, :name) {output(node.resolved_name)}
  if node.style == :compressed
    output(":")
    for_node(node, :value) {output(node.resolved_value)}
  else
    output(": ")
    for_node(node, :value) {output(node.resolved_value)}
    output(";")
  end
end
visit_root(node) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 119
def visit_root(node)
  node.children.each do |child|
    next if child.invisible?
    visit(child)
    unless node.style == :compressed
      output "\n"
      if child.is_a?(Sass::Tree::DirectiveNode) && child.has_children && !child.bubbles?
        output "\n"
      end
    end
  end
  rstrip!
  if node.style == :compressed && ends_with?(";")
    erase! 1
  end
  return "" if @result.empty?

  output "\n"

  unless Sass::Util.ruby1_8? || @result.ascii_only?
    if node.style == :compressed
      # A byte order mark is sufficient to tell browsers that this
      # file is UTF-8 encoded, and will override any other detection
      # methods as per http://encoding.spec.whatwg.org/#decode-and-encode.
      prepend! "\uFEFF"
    else
      prepend! "@charset \"UTF-8\";\n"
    end
  end

  @result
rescue Sass::SyntaxError => e
  e.sass_template ||= node.template
  raise e
end
visit_rule(node) click to toggle source

@comment

rubocop:disable MethodLength
# File lib/sass/tree/visitors/to_css.rb, line 280
def visit_rule(node)
  with_tabs(@tabs + node.tabs) do
    rule_separator = node.style == :compressed ? ',' : ', '
    line_separator =
      case node.style
      when :nested, :expanded; "\n"
      when :compressed; ""
      else; " "
      end
    rule_indent = '  ' * @tabs
    per_rule_indent, total_indent = if [:nested, :expanded].include?(node.style)
                                      [rule_indent, '']
                                    else
                                      ['', rule_indent]
                                    end

    joined_rules = node.resolved_rules.members.map do |seq|
      next if seq.has_placeholder?
      rule_part = seq.to_s
      if node.style == :compressed
        rule_part.gsub!(/([^,])\s*\n\s*/m, '\1 ')
        rule_part.gsub!(/\s*([-,+>])\s*/m, '\1')
        rule_part.strip!
      end
      rule_part
    end.compact.join(rule_separator)

    joined_rules.lstrip!
    joined_rules.gsub!(/\s*\n\s*/, "#{line_separator}#{per_rule_indent}")

    old_spaces = '  ' * @tabs
    if node.style != :compressed
      if node.options[:debug_info] && !@in_directive
        visit(debug_info_rule(node.debug_info, node.options))
        output "\n"
      elsif node.options[:trace_selectors]
        output("#{old_spaces}/* ")
        output(node.stack_trace.gsub("\n", "\n   #{old_spaces}"))
        output(" */\n")
      elsif node.options[:line_comments]
        output("#{old_spaces}/* line #{node.line}")

        if node.filename
          relative_filename =
            if node.options[:css_filename]
              begin
                Sass::Util.relative_path_from(
                  node.filename, File.dirname(node.options[:css_filename])).to_s
              rescue ArgumentError
                nil
              end
            end
          relative_filename ||= node.filename
          output(", #{relative_filename}")
        end

        output(" */\n")
      end
    end

    end_props, trailer, tabs  = '', '', 0
    if node.style == :compact
      separator, end_props, bracket = ' ', ' ', ' { '
      trailer = "\n" if node.group_end
    elsif node.style == :compressed
      separator, bracket = ';', '{'
    else
      tabs = @tabs + 1
      separator, bracket = "\n", " {\n"
      trailer = "\n" if node.group_end
      end_props = (node.style == :expanded ? "\n" + old_spaces : ' ')
    end
    output(total_indent + per_rule_indent)
    for_node(node, :selector) {output(joined_rules)}
    output(bracket)

    with_tabs(tabs) do
      node.children.each_with_index do |child, i|
        if i > 0
          if separator.start_with?(";") && ends_with?(";")
            erase! 1
          end
          output(separator)
        end
        visit(child)
      end
    end
    if node.style == :compressed && ends_with?(";")
      erase! 1
    end

    output(end_props)
    output("}" + trailer)
  end
end
visit_supports(node) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 255
def visit_supports(node)
  visit_media(node)
end
with_tabs(tabs) { || ... } click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 32
def with_tabs(tabs)
  old_tabs, @tabs = @tabs, tabs
  yield
ensure
  @tabs = old_tabs
end

Private Instance Methods

debug_info_rule(debug_info, options) click to toggle source
# File lib/sass/tree/visitors/to_css.rb, line 384
def debug_info_rule(debug_info, options)
  node = Sass::Tree::DirectiveNode.resolved("@media -sass-debug-info")
  Sass::Util.hash_to_a(debug_info.map {|k, v| [k.to_s, v.to_s]}).each do |k, v|
    rule = Sass::Tree::RuleNode.new([""])
    rule.resolved_rules = Sass::Selector::CommaSequence.new(
      [Sass::Selector::Sequence.new(
          [Sass::Selector::SimpleSequence.new(
              [Sass::Selector::Element.new(k.to_s.gsub(/[^\w-]/, "\\\\\\0"), nil)],
              false)
          ])
      ])
    prop = Sass::Tree::PropNode.new([""], Sass::Script::Value::String.new(''), :new)
    prop.resolved_name = "font-family"
    prop.resolved_value = Sass::SCSS::RX.escape_ident(v.to_s)
    rule << prop
    node << rule
  end
  node.options = options.merge(:debug_info => false,
                               :line_comments => false,
                               :style => :compressed)
  node
end