class Asciidoctor::PreprocessorReader

Public: Methods for retrieving lines from AsciiDoc source files, evaluating preprocessor directives as each line is read off the Array of lines.

Attributes

include_stack[R]
includes[R]

Public Class Methods

new(document, data = nil, cursor = nil) click to toggle source

Public: Initialize the PreprocessorReader object

Calls superclass method Asciidoctor::Reader.new
# File lib/asciidoctor/reader.rb, line 538
def initialize document, data = nil, cursor = nil
  @document = document
  super data, cursor
  include_depth_default = document.attributes.fetch('max-include-depth', 64).to_i
  include_depth_default = 0 if include_depth_default < 0
  # track both absolute depth for comparing to size of include stack and relative depth for reporting
  @maxdepth = {:abs => include_depth_default, :rel => include_depth_default}
  @include_stack = []
  @includes = (document.references[:includes] ||= [])
  @skipping = false
  @conditional_stack = []
  @include_processors = nil
end

Public Instance Methods

exceeded_max_depth?() click to toggle source
# File lib/asciidoctor/reader.rb, line 1005
def exceeded_max_depth?
  if (abs_maxdepth = @maxdepth[:abs]) > 0 && @include_stack.size >= abs_maxdepth
    @maxdepth[:rel]
  else
    false
  end
end
include_depth() click to toggle source
# File lib/asciidoctor/reader.rb, line 1001
def include_depth
  @include_stack.size 
end
include_processors?() click to toggle source
# File lib/asciidoctor/reader.rb, line 1117
def include_processors?
  if @include_processors.nil?
    if @document.extensions? && @document.extensions.include_processors?
      @include_processors = @document.extensions.load_include_processors(@document)
      true
    else
      @include_processors = false
      false
    end
  else
    @include_processors != false
  end
end
peek_line(direct = false) click to toggle source

Public: Override the Asciidoctor::Reader#peek_line method to pop the include stack if the last line has been reached and there's at least one include on the stack.

Returns the next line of the source data as a String if there are lines remaining in the current include context or a parent include context. Returns nil if there are no more lines remaining and the include stack is empty.

Calls superclass method Asciidoctor::Reader#peek_line
# File lib/asciidoctor/reader.rb, line 651
def peek_line direct = false
  if (line = super)
    line
  elsif @include_stack.empty?
    nil
  else
    pop_include
    peek_line direct
  end
end
pop_include() click to toggle source
# File lib/asciidoctor/reader.rb, line 990
def pop_include
  if @include_stack.size > 0
    @lines, @file, @dir, @path, @lineno, @maxdepth, @process_lines = @include_stack.pop
    # FIXME kind of a hack
    #Document::AttributeEntry.new('infile', @file).save_to_next_block @document
    #Document::AttributeEntry.new('indir', File.dirname(@file)).save_to_next_block @document
    @eof = @lines.empty?
    @look_ahead = 0
  end
end
prepare_lines(data, opts = {}) click to toggle source
# File lib/asciidoctor/reader.rb, line 552
def prepare_lines data, opts = {}
  if data.is_a?(String)
    if ::Asciidoctor::FORCE_ENCODING
      result = data.each_line.map {|line| "#{line.rstrip.force_encoding ::Encoding::UTF_8}#{::Asciidoctor::EOL}" }
    else
      result = data.each_line.map {|line| "#{line.rstrip}#{::Asciidoctor::EOL}" }
    end
  else
    if ::Asciidoctor::FORCE_ENCODING
      result = data.map {|line| "#{line.rstrip.force_encoding ::Encoding::UTF_8}#{::Asciidoctor::EOL}" }
    else
      result = data.map {|line| "#{line.rstrip}#{::Asciidoctor::EOL}" }
    end
  end

  # QUESTION should this work for AsciiDoc table cell content? Currently it does not.
  unless @document.nil? || !(@document.attributes.has_key? 'skip-front-matter')
    if (front_matter = skip_front_matter! result)
      @document.attributes['front-matter'] = front_matter.join.chomp
    end
  end

  # QUESTION should we chomp last line? (with or without the condense flag?)
  if opts.fetch(:condense, true)
    result.shift && @lineno += 1 while !(first = result.first).nil? && first == ::Asciidoctor::EOL
    result.pop while !(last = result.last).nil? && last == ::Asciidoctor::EOL
  end

  if (indent = opts.fetch(:indent, nil))
    Lexer.reset_block_indent! result, indent.to_i
  end

  result
end
preprocess_conditional_inclusion(directive, target, delimiter, text) click to toggle source

Internal: Preprocess the directive (macro) to conditionally include content.

Preprocess the conditional inclusion directive (ifdef, ifndef, ifeval, endif) under the cursor. If the Reader is currently skipping content, then simply track the open and close delimiters of any nested conditional blocks. If the Reader is not skipping, mark whether the condition is satisfied and continue preprocessing recursively until the next line of available content is found.

directive - The conditional inclusion directive (ifdef, ifndef, ifeval, endif) target - The target, which is the name of one or more attributes that are

used in the condition (blank in the case of the ifeval directive)

delimiter - The conditional delimiter for multiple attributes ('+' means all

attributes must be defined or undefined, ',' means any of the attributes
can be defined or undefined.

text - The text associated with this directive (occurring between the square brackets)

Used for a single-line conditional block in the case of the ifdef or
ifndef directives, and for the conditional expression for the ifeval directive.

returns a Boolean indicating whether the cursor should be advanced

# File lib/asciidoctor/reader.rb, line 682
def preprocess_conditional_inclusion directive, target, delimiter, text
  # must have a target before brackets if ifdef or ifndef
  # must not have text between brackets if endif
  # don't honor match if it doesn't meet this criteria
  # QUESTION should we warn for these bogus declarations?
  if ((directive == 'ifdef' || directive == 'ifndef') && target.empty?) ||
      (directive == 'endif' && !text.nil?)
    return false
  end

  if directive == 'endif'
    stack_size = @conditional_stack.size
    if stack_size > 0
      pair = @conditional_stack.last
      if target.empty? || target == pair[:target]
        @conditional_stack.pop
        @skipping = @conditional_stack.empty? ? false : @conditional_stack.last[:skipping]
      else
        warn "asciidoctor: ERROR: #{line_info}: mismatched macro: endif::#{target}[], expected endif::#{pair[:target]}[]"
      end
    else
      warn "asciidoctor: ERROR: #{line_info}: unmatched macro: endif::#{target}[]"
    end
    return true
  end

  skip = false
  unless @skipping
    # QUESTION any way to wrap ifdef & ifndef logic up together?
    case directive
    when 'ifdef'
      case delimiter
      when nil
        # if the attribute is undefined, then skip
        skip = !@document.attributes.has_key?(target)
      when ','
        # if any attribute is defined, then don't skip
        skip = !target.split(',').detect {|name| @document.attributes.has_key? name }
      when '+'
        # if any attribute is undefined, then skip
        skip = target.split('+').detect {|name| !@document.attributes.has_key? name }
      end
    when 'ifndef'
      case delimiter
      when nil
        # if the attribute is defined, then skip
        skip = @document.attributes.has_key?(target)
      when ','
        # if any attribute is undefined, then don't skip
        skip = !target.split(',').detect {|name| !@document.attributes.has_key? name }
      when '+'
        # if any attribute is defined, then skip
        skip = target.split('+').detect {|name| @document.attributes.has_key? name }
      end
    when 'ifeval'
      # the text in brackets must match an expression
      # don't honor match if it doesn't meet this criteria
      if !target.empty? || !(expr_match = text.strip.match(REGEXP[:eval_expr]))
        return false
      end

      lhs = resolve_expr_val expr_match[1]
      # regex enforces a restrict set of math-related operations
      op = expr_match[2]
      rhs = resolve_expr_val expr_match[3]

      skip = !(lhs.send op.to_sym, rhs)
    end
  end

  # conditional inclusion block
  if directive == 'ifeval' || text.nil?
    @skipping = true if skip
    @conditional_stack << {:target => target, :skip => skip, :skipping => @skipping}
  # single line conditional inclusion
  else
    unless @skipping || skip
      # FIXME slight hack to skip past conditional line
      # but keep our synthetic line marked as processed
      conditional_line = peek_line true
      replace_line "#{text.rstrip}#{::Asciidoctor::EOL}"
      unshift conditional_line
      return true
    end
  end

  true
end
preprocess_include(target, raw_attributes) click to toggle source

Internal: Preprocess the directive (macro) to include the target document.

Preprocess the directive to include the target document. The scenarios are as follows:

If SafeMode is SECURE or greater, the directive is ignore and the include directive line is emitted verbatim.

Otherwise, if an include processor is specified pass the target and attributes to that processor and expect an Array of String lines in return.

Otherwise, if the max depth is greater than 0, and is not exceeded by the stack size, normalize the target path and read the lines onto the beginning of the Array of source data.

If none of the above apply, emit the include directive line verbatim.

target - The name of the source document to include as specified in the

target slot of the include::[] macro

returns a Boolean indicating whether the line under the cursor has changed.

# File lib/asciidoctor/reader.rb, line 792
def preprocess_include target, raw_attributes
  target = @document.sub_attributes target, :attribute_missing => 'drop-line'
  if target.empty?
    if @document.attributes.fetch('attribute-missing', COMPLIANCE[:attribute_missing]) == 'skip'
      false
    else
      advance
      true
    end
  # assume that if an include processor is given, the developer wants
  # to handle when and how to process the include
  elsif include_processors? &&
      (processor = @include_processors.find {|candidate| candidate.handles? target })
    advance
    # QUESTION should we use @document.parse_attribues?
    processor.process self, target, AttributeList.new(raw_attributes).parse
    true
  # if running in SafeMode::SECURE or greater, don't process this directive
  # however, be friendly and at least make it a link to the source document
  elsif @document.safe >= SafeMode::SECURE
    replace_line "link:#{target}[]#{::Asciidoctor::EOL}"
    # TODO make creating the output target a helper method
    #output_target = %(#{File.join(File.dirname(target), File.basename(target, File.extname(target)))}#{@document.attributes['outfilesuffix']})
    #unshift "link:#{output_target}[]#{::Asciidoctor::EOL}"
    true
  elsif (abs_maxdepth = @maxdepth[:abs]) > 0 && @include_stack.size >= abs_maxdepth
    warn %Q(asciidoctor: ERROR: #{line_info}: maximum include depth of #{@maxdepth[:rel]} exceeded)
    false
  elsif abs_maxdepth > 0
    if target.include?(':') && target.match(REGEXP[:uri_sniff])
      unless @document.attributes.has_key? 'allow-uri-read'
        replace_line "link:#{target}[]#{::Asciidoctor::EOL}"
        return true
      end

      target_type = :uri
      include_file = path = target
      if @document.attributes.has_key? 'cache-uri'
        # caching requires the open-uri-cached gem to be installed
        # processing will be automatically aborted if these libraries can't be opened
        Helpers.require_library 'open-uri/cached', 'open-uri-cached'
      else
        Helpers.require_library 'open-uri'
      end
    else
      target_type = :file
      # include file is resolved relative to dir of current include, or base_dir if within original docfile
      include_file = @document.normalize_system_path(target, @dir, nil, :target_name => 'include file')
      if !File.file?(include_file)
        warn "asciidoctor: WARNING: #{line_info}: include file not found: #{include_file}"
        advance
        return true
      end
      #path = @document.relative_path include_file
      path = PathResolver.new.relative_path include_file, @document.base_dir
    end

    inc_lines = nil
    tags = nil
    attributes = {}
    if !raw_attributes.empty?
      # QUESTION should we use @document.parse_attribues?
      attributes = AttributeList.new(raw_attributes).parse
      if attributes.has_key? 'lines'
        inc_lines = []
        attributes['lines'].split(REGEXP[:ssv_or_csv_delim]).each do |linedef|
          if linedef.include?('..')
            from, to = linedef.split('..').map(&:to_i)
            if to == -1
              inc_lines << from
              inc_lines << 1.0/0.0
            else
              inc_lines.concat Range.new(from, to).to_a
            end
          else
            inc_lines << linedef.to_i
          end
        end
        inc_lines = inc_lines.sort.uniq
      elsif attributes.has_key? 'tag'
        tags = [attributes['tag']]
      elsif attributes.has_key? 'tags'
        tags = attributes['tags'].split(REGEXP[:ssv_or_csv_delim]).uniq
      end
    end
    if !inc_lines.nil?
      if !inc_lines.empty?
        selected = []
        inc_line_offset = 0
        inc_lineno = 0
        begin
          open(include_file) do |f|
            f.each_line do |l|
              inc_lineno += 1
              take = inc_lines.first
              if take.is_a?(Float) && take.infinite?
                selected.push l
                inc_line_offset = inc_lineno if inc_line_offset == 0
              else
                if f.lineno == take
                  selected.push l
                  inc_line_offset = inc_lineno if inc_line_offset == 0
                  inc_lines.shift
                end
                break if inc_lines.empty?
              end
            end
          end
        rescue
          warn "asciidoctor: WARNING: #{line_info}: include #{target_type} not readable: #{include_file}"
          advance
          return true
        end
        advance
        # FIXME not accounting for skipped lines in reader line numbering
        push_include selected, include_file, path, inc_line_offset, attributes
      end
    elsif !tags.nil?
      if !tags.empty?
        selected = []
        inc_line_offset = 0
        inc_lineno = 0
        active_tag = nil
        begin
          open(include_file) do |f|
            f.each_line do |l|
              inc_lineno += 1
              # must force encoding here since we're performing String operations on line
              l.force_encoding(::Encoding::UTF_8) if ::Asciidoctor::FORCE_ENCODING
              if !active_tag.nil?
                if l.include?("end::#{active_tag}[]")
                  active_tag = nil
                else
                  selected.push l
                  inc_line_offset = inc_lineno if inc_line_offset == 0
                end
              else
                tags.each do |tag|
                  if l.include?("tag::#{tag}[]")
                    active_tag = tag
                    break
                  end
                end
              end
            end
          end
        rescue
          warn "asciidoctor: WARNING: #{line_info}: include #{target_type} not readable: #{include_file}"
          advance
          return true
        end
        advance
        # FIXME not accounting for skipped lines in reader line numbering
        push_include selected, include_file, path, inc_line_offset, attributes
      end
    else
      begin
        advance
        push_include open(include_file) {|f| f.read }, include_file, path, 1, attributes
      rescue
        warn "asciidoctor: WARNING: #{line_info}: include #{target_type} not readable: #{include_file}"
        advance
        return true
      end
    end
    true
  else
    false
  end
end
process_line(line) click to toggle source
# File lib/asciidoctor/reader.rb, line 587
def process_line line
  return line unless @process_lines

  if line.chomp.empty?
    @look_ahead += 1
    return ''
  end

  macroish = line.include?('::') && line.include?('[')
  if macroish && line.include?('if') && (match = line.match(REGEXP[:ifdef_macro]))
    # if escaped, mark as processed and return line unescaped
    if line.start_with? '\'
      @unescape_next_line = true
      @look_ahead += 1
      line[1..-1]
    else
      if preprocess_conditional_inclusion(*match.captures)
        # move the pointer past the conditional line
        advance
        # treat next line as uncharted territory
        nil
      else
        # the line was not a valid conditional line
        # mark it as visited and return it
        @look_ahead += 1
        line
      end
    end
  elsif @skipping
    advance
    nil 
  elsif macroish && line.include?('include::') && (match = line.match(REGEXP[:include_macro]))
    # if escaped, mark as processed and return line unescaped
    if line.start_with? '\'
      @unescape_next_line = true
      @look_ahead += 1
      line[1..-1]
    else
      # QUESTION should we strip whitespace from raw attributes in Substituters#parse_attributes? (check perf)
      if preprocess_include match[1], match[2].strip
        # peek again since the content has changed
        nil
      else
        # the line was not a valid include line and is unchanged
        # mark it as visited and return it
        @look_ahead += 1
        line
      end
    end
  else
    # optimization to inline super
    #super
    @look_ahead += 1
    line
  end
end
push_include(data, file = nil, path = nil, lineno = 1, attributes = {}) click to toggle source
# File lib/asciidoctor/reader.rb, line 963
def push_include data, file = nil, path = nil, lineno = 1, attributes = {}
  @include_stack << [@lines, @file, @dir, @path, @lineno, @maxdepth, @process_lines]
  @includes << Helpers.rootname(path)
  @file = file
  @dir = File.dirname file
  @path = path
  @lineno = lineno
  # NOTE only process lines in AsciiDoc files
  @process_lines = ASCIIDOC_EXTENSIONS[File.extname(@file)]
  if attributes.has_key? 'depth'
    depth = attributes['depth'].to_i
    depth = 1 if depth <= 0
    @maxdepth = {:abs => (@include_stack.size - 1) + depth, :rel => depth}
  end
  # effectively fill the buffer
  @lines = prepare_lines data, :condense => false, :indent => attributes['indent']
  # FIXME kind of a hack
  #Document::AttributeEntry.new('infile', @file).save_to_next_block @document
  #Document::AttributeEntry.new('indir', File.dirname(@file)).save_to_next_block @document
  if @lines.empty?
    pop_include
  else
    @eof = false
    @look_ahead = 0
  end
end
resolve_expr_val(str) click to toggle source

Private: Resolve the value of one side of the expression

Examples

expr = '"value"'
resolve_expr_val(expr)
# => "value"

expr = '"value'
resolve_expr_val(expr)
# => "\"value"

expr = '"{undefined}"'
resolve_expr_val(expr)
# => ""

expr = '{undefined}'
resolve_expr_val(expr)
# => nil

expr = '2'
resolve_expr_val(expr)
# => 2

@document.attributes['name'] = 'value'
expr = '"{name}"'
resolve_expr_val(expr)
# => "value"

Returns The value of the expression, coerced to the appropriate type

# File lib/asciidoctor/reader.rb, line 1081
def resolve_expr_val(str)
  val = str
  type = nil

  if val.start_with?('"') && val.end_with?('"') ||
      val.start_with?('\') && val.end_with?('\')
    type = :string
    val = val[1...-1]
  end

  # QUESTION should we substitute first?
  if val.include? '{'
    val = @document.sub_attributes val
  end

  unless type == :string
    if val.empty?
      val = nil
    elsif val.strip.empty?
      val = ' '
    elsif val == 'true'
      val = true
    elsif val == 'false'
      val = false
    elsif val.include?('.')
      val = val.to_f
    else
      # fallback to coercing to integer, since we
      # require string values to be explicitly quoted
      val = val.to_i
    end
  end

  val
end
shift() click to toggle source

TODO Document this override also, we now have the field in the super class, so perhaps just implement the logic there?

Calls superclass method Asciidoctor::Reader#shift
# File lib/asciidoctor/reader.rb, line 1016
def shift
  if @unescape_next_line
    @unescape_next_line = false
    super[1..-1]
  else
    super
  end
end
skip_front_matter!(data, increment_linenos = true) click to toggle source

Private: Ignore front-matter, commonly used in static site generators

# File lib/asciidoctor/reader.rb, line 1026
def skip_front_matter! data, increment_linenos = true
  front_matter = nil
  if data.size > 0 && data.first.chomp == '---'
    original_data = data.dup
    front_matter = []
    data.shift
    @lineno += 1 if increment_linenos
    while !data.empty? && data.first.chomp != '---'
      front_matter.push data.shift
      @lineno += 1 if increment_linenos
    end

    if data.empty?
      data.unshift(*original_data)
      @lineno = 0 if increment_linenos
      front_matter = nil
    else
      data.shift
      @lineno += 1 if increment_linenos
    end
  end

  front_matter
end
to_s() click to toggle source
# File lib/asciidoctor/reader.rb, line 1131
def to_s
  %Q(#{self.class.name} [path: #{@path}, line #: #{@lineno}, include depth: #{@include_stack.size}, include stack: [#{@include_stack.map {|inc| inc.to_s}.join ', '}]])
end