class RDoc::Markup::PreProcess - rdoc-4.1.2 Documentation

# class RDoc::Markup::PreProcess

Handle common directives that can occur in a block of text:

    :include: filename

Directives can be escaped by preceding them with a backslash.

RDoc plugin authors can register additional directives to be handled by using ::register.

Any directive that is not built-in to RDoc (including those registered via plugins) will be stored in the metadata hash on the CodeObject the comment is attached to. See Directives at RDoc::Markup for the list of built-in directives.

### Attributes

options[RW]

An RDoc::Options instance that will be filled in with overrides from directives

### Public Class Methods

new(input_file_name, include_path) click to toggle source

Creates a new pre-processor for `input_file_name` that will look for included files in `include_path`

    # File lib/rdoc/markup/pre_process.rb, line 77
    def initialize(input_file_name, include_path)
      @input_file_name = input_file_name
      @include_path = include_path
      @options = nil
    end

post_process(&block) click to toggle source

Adds a post-process handler for directives. The handler will be called with the result RDoc::Comment (or text String) and the code object for the comment (if any).

    # File lib/rdoc/markup/pre_process.rb, line 29
    def self.post_process &block
      @post_processors << block
    end

post_processors() click to toggle source

Registered post-processors

    # File lib/rdoc/markup/pre_process.rb, line 36
    def self.post_processors
      @post_processors
    end

register(directive, &block) click to toggle source

Registers `directive` as one handled by RDoc. If a block is given the directive will be replaced by the result of the block, otherwise the directive will be removed from the processed text.

The block will be called with the directive name and the directive parameter:

    RDoc::Markup::PreProcess.register 'my-directive' do |directive, param|
      # replace text, etc.
    end

    # File lib/rdoc/markup/pre_process.rb, line 52
    def self.register directive, &block
      @registered[directive] = block
    end

registered() click to toggle source

Registered directives

    # File lib/rdoc/markup/pre_process.rb, line 59
    def self.registered
      @registered
    end

reset() click to toggle source

Clears all registered directives and post-processors

    # File lib/rdoc/markup/pre_process.rb, line 66
    def self.reset
      @post_processors = []
      @registered = {}
    end

### Public Instance Methods

find_include_file(name) click to toggle source

Look for the given file in the directory containing the current file, and then in each of the directories specified in the RDOC_INCLUDE path

    # File lib/rdoc/markup/pre_process.rb, line 282
    def find_include_file(name)
      to_search = [File.dirname(@input_file_name)].concat @include_path
      to_search.each do |dir|
        full_name = File.join(dir, name)
        stat = File.stat(full_name) rescue next
        return full_name if stat.readable?
      end
      nil
    end

handle(text, code_object = nil, &block) click to toggle source

Look for directives in the given `text`.

Options that we don't handle are yielded. If the block returns false the directive is restored to the text. If the block returns nil or no block was given the directive is handled according to the registered directives. If a String was returned the directive is replaced with the string.

If no matching directive was registered the directive is restored to the text.

If `code_object` is given and the directive is unknown then the directive's parameter is set as metadata on the `code_object`. See RDoc::CodeObject#metadata for details.

    # File lib/rdoc/markup/pre_process.rb, line 98
    def handle text, code_object = nil, &block
      if RDoc::Comment === text then
        comment = text
        text = text.text
      end

      encoding = text.encoding if defined?(Encoding)

      # regexp helper (square brackets for optional)
      # $1      $2  $3        $4      $5
      # [prefix][\]:directive:[spaces][param]newline
      text.gsub!(/^([ \t]*(?:#|\/?\*)?[ \t]*)(\?):(\w+):([ \t]*)(.+)?(\r?\n|$)/) do
        # skip something like ':toto::'
        next $& if $4.empty? and $5 and $5[0, 1] == ':'

        # skip if escaped
        next "#$1:#$3:#$4#$5\n" unless $2.empty?

        # This is not in handle_directive because I didn't want to pass another
        # argument into it
        if comment and $3 == 'markup' then
          next "#{$1.strip}\n" unless $5
          comment.format = $5.downcase
          next "#{$1.strip}\n"
        end

        handle_directive $1, $3, $5, code_object, encoding, &block
      end

      comment = text unless comment

      self.class.post_processors.each do |handler|
        handler.call comment, code_object
      end

      text
    end

handle_directive(prefix, directive, param, code_object = nil, encoding = nil) { |directive, param| ... } click to toggle source

Performs the actions described by `directive` and its parameter `param`.

`code_object` is used for directives that operate on a class or module. `prefix` is used to ensure the replacement for handled directives is correct. `encoding` is used for the `include` directive.

For a list of directives in RDoc see RDoc::Markup.

    # File lib/rdoc/markup/pre_process.rb, line 147
    def handle_directive prefix, directive, param, code_object = nil,
                         encoding = nil
      blankline = "#{prefix.strip}\n"
      directive = directive.downcase

      case directive
      when 'arg', 'args' then
        return "#{prefix}:#{directive}: #{param}\n" unless code_object

        code_object.params = param

        blankline
      when 'category' then
        if RDoc::Context === code_object then
          section = code_object.add_section param
          code_object.temporary_section = section
        end

        blankline # ignore category if we're not on an RDoc::Context
      when 'doc' then
        return blankline unless code_object
        code_object.document_self = true
        code_object.force_documentation = true

        blankline
      when 'enddoc' then
        return blankline unless code_object
        code_object.done_documenting = true

        blankline
      when 'include' then
        filename = param.split.first
        include_file filename, prefix, encoding
      when 'main' then
        @options.main_page = param if @options.respond_to? :main_page

        blankline
      when 'nodoc' then
        return blankline unless code_object
        code_object.document_self = nil # notify nodoc
        code_object.document_children = param !~ /all/i

        blankline
      when 'notnew', 'not_new', 'not-new' then
        return blankline unless RDoc::AnyMethod === code_object

        code_object.dont_rename_initialize = true

        blankline
      when 'startdoc' then
        return blankline unless code_object

        code_object.start_doc
        code_object.force_documentation = true

        blankline
      when 'stopdoc' then
        return blankline unless code_object

        code_object.stop_doc

        blankline
      when 'title' then
        @options.default_title = param if @options.respond_to? :default_title=

        blankline
      when 'yield', 'yields' then
        return blankline unless code_object
        # remove parameter &block
        code_object.params.sub!(/,?\s*&\w+/, '') if code_object.params

        code_object.block_params = param

        blankline
      else
        result = yield directive, param if block_given?

        case result
        when nil then
          code_object.metadata[directive] = param if code_object

          if RDoc::Markup::PreProcess.registered.include? directive then
            handler = RDoc::Markup::PreProcess.registered[directive]
            result = handler.call directive, param if handler
          else
            result = "#{prefix}:#{directive}: #{param}\n"
          end
        when false then
          result = "#{prefix}:#{directive}: #{param}\n"
        end

        result
      end
    end

include_file(name, indent, encoding) click to toggle source

Handles the `:include: filename` directive.

If the first line of the included file starts with '#', and contains an encoding information in the form 'coding:' or 'coding=', it is removed.

If all lines in the included file start with a '#', this leading '#' is removed before inclusion. The included content is indented like the `:include:` directive.

    # File lib/rdoc/markup/pre_process.rb, line 257
    def include_file name, indent, encoding
      full_name = find_include_file name

      unless full_name then
        warn "Couldn't find file to include '#{name}' from #{@input_file_name}"
        return ''
      end

      content = RDoc::Encoding.read_file full_name, encoding, true

      # strip magic comment
      content = content.sub(/\A# .*coding[=:].*$/, '').lstrip

      # strip leading '#'s, but only if all lines start with them
      if content =~ /^[^#]/ then
        content.gsub(/^/, indent)
      else
        content.gsub(/^#?/, indent)
      end
    end