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RDoc::Parser::Ruby

Extracts code elements from a source file returning a TopLevel object containing the constituent file elements.

This file is based on rtags

RubyParser understands how to document:

  • classes

  • modules

  • methods

  • constants

  • aliases

  • private, public, protected

  • private_class_function, public_class_function

  • module_function

  • attr, attr_reader, attr_writer, attr_accessor

  • extra accessors given on the command line

  • metaprogrammed methods

  • require

  • include

Method Arguments

The parser extracts the arguments from the method definition. You can override this with a custom argument definition using the :call-seq: directive:

##
# This method can be called with a range or an offset and length
#
# :call-seq:
#   my_method(Range)
#   my_method(offset, length)

def my_method(*args)
end

The parser extracts yield expressions from method bodies to gather the yielded argument names. If your method manually calls a block instead of yielding or you want to override the discovered argument names use the :yields: directive:

##
# My method is awesome

def my_method(&block) # :yields: happy, times
  block.call 1, 2
end

Metaprogrammed Methods

To pick up a metaprogrammed method, the parser looks for a comment starting with ‘##’ before an identifier:

##
# This is a meta-programmed method!

add_my_method :meta_method, :arg1, :arg2

The parser looks at the token after the identifier to determine the name, in this example, :meta_method. If a name cannot be found, a warning is printed and ‘unknown is used.

You can force the name of a method using the :method: directive:

##
# :method: woo_hoo!

By default, meta-methods are instance methods. To indicate that a method is a singleton method instead use the :singleton-method: directive:

##
# :singleton-method:

You can also use the :singleton-method: directive with a name:

##
# :singleton-method: woo_hoo!

Additionally you can mark a method as an attribute by using :attr:, :attr_reader:, :attr_writer: or :attr_accessor:. Just like for :method:, the name is optional.

##
# :attr_reader: my_attr_name

Hidden methods and attributes

You can provide documentation for methods that don’t appear using the :method:, :singleton-method: and :attr: directives:

##
# :attr_writer: ghost_writer
# There is an attribute here, but you can't see it!

##
# :method: ghost_method
# There is a method here, but you can't see it!

##
# this is a comment for a regular method

def regular_method() end

Note that by default, the :method: directive will be ignored if there is a standard rdocable item following it.

Public Class Methods

new(top_level, file_name, content, options, stats) click to toggle source

Creates a new Ruby parser.

 
               # File rdoc/parser/ruby.rb, line 168
def initialize(top_level, file_name, content, options, stats)
  super

  @size = 0
  @token_listeners = nil
  @scanner = RDoc::RubyLex.new content, @options
  @scanner.exception_on_syntax_error = false
  @prev_seek = nil

  @encoding = nil
  @encoding = @options.encoding if Object.const_defined? :Encoding

  reset
end
            

Public Instance Methods

collect_first_comment() click to toggle source

Look for the first comment in a file that isn’t a shebang line.

 
               # File rdoc/parser/ruby.rb, line 186
def collect_first_comment
  skip_tkspace
  comment = ''
  comment.force_encoding @encoding if @encoding
  first_line = true

  tk = get_tk

  while TkCOMMENT === tk
    if first_line and tk.text =~ /\A#!/ then
      skip_tkspace
      tk = get_tk
    elsif first_line and tk.text =~ /\A#\s*-\*-/ then
      first_line = false
      skip_tkspace
      tk = get_tk
    else
      first_line = false
      comment << tk.text << "\n"
      tk = get_tk

      if TkNL === tk then
        skip_tkspace false
        tk = get_tk
      end
    end
  end

  unget_tk tk

  comment
end
            
error(msg) click to toggle source

Aborts with msg

 
               # File rdoc/parser/ruby.rb, line 222
def error(msg)
  msg = make_message msg

  abort msg
end
            
extract_call_seq(comment, meth) click to toggle source

Look for a ‘call-seq’ in the comment, and override the normal parameter stuff

 
               # File rdoc/parser/ruby.rb, line 234
def extract_call_seq(comment, meth)
  if comment.sub!(/:?call-seq:(.*?)(^\s*#?\s*$|\z)/m, '') then
    seq = $1
    seq.gsub!(/^\s*\#\s*/, '')
    meth.call_seq = seq
  end

  meth
end
            
get_bool() click to toggle source

Looks for a true or false token. Returns false if TkFALSE or TkNIL are found.

 
               # File rdoc/parser/ruby.rb, line 248
def get_bool
  skip_tkspace
  tk = get_tk
  case tk
  when TkTRUE
    true
  when TkFALSE, TkNIL
    false
  else
    unget_tk tk
    true
  end
end
            
get_class_or_module(container) click to toggle source
Look for the name of a class of module (optionally with a leading

or

with

separated named) and return the ultimate name, the associated

container, and the given name (with the ::).

 
               # File rdoc/parser/ruby.rb, line 267
def get_class_or_module(container)
  skip_tkspace
  name_t = get_tk
  given_name = ''

  # class ::A -> A is in the top level
  case name_t
  when TkCOLON2, TkCOLON3 then # bug
    name_t = get_tk
    container = @top_level
    given_name << '::'
  end

  skip_tkspace false
  given_name << name_t.name

  while TkCOLON2 === peek_tk do
    prev_container = container
    container = container.find_module_named name_t.name
    unless container then
      container = prev_container.add_module RDoc::NormalModule, name_t.name
    end
    get_tk
    name_t = get_tk
    given_name << '::' << name_t.name
  end
  skip_tkspace false
  return [container, name_t, given_name]
end
            
get_class_specification() click to toggle source

Return a superclass, which can be either a constant of an expression

 
               # File rdoc/parser/ruby.rb, line 300
def get_class_specification
  tk = get_tk
  return "self" if TkSELF === tk

  res = ""
  while TkCOLON2 === tk or TkCOLON3 === tk or TkCONSTANT === tk do
    res += tk.name
    tk = get_tk
  end

  unget_tk(tk)
  skip_tkspace false

  get_tkread # empty out read buffer

  tk = get_tk

  case tk
  when TkNL, TkCOMMENT, TkSEMICOLON then
    unget_tk(tk)
    return res
  end

  res += parse_call_parameters(tk)
  res
end
            
get_constant() click to toggle source

Parse a constant, which might be qualified by one or more class or module names

 
               # File rdoc/parser/ruby.rb, line 331
  def get_constant
    res = ""
    skip_tkspace false
    tk = get_tk

    while TkCOLON2 === tk or TkCOLON3 === tk or TkCONSTANT === tk do
      res += tk.name
      tk = get_tk
    end

#      if res.empty?
#        warn("Unexpected token #{tk} in constant")
#      end
    unget_tk(tk)
    res
  end
            
get_constant_with_optional_parens() click to toggle source

Get a constant that may be surrounded by parens

 
               # File rdoc/parser/ruby.rb, line 351
def get_constant_with_optional_parens
  skip_tkspace false

  nest = 0

  while TkLPAREN === (tk = peek_tk) or TkfLPAREN === tk do
    get_tk
    skip_tkspace
    nest += 1
  end

  name = get_constant

  while nest > 0
    skip_tkspace
    tk = get_tk
    nest -= 1 if TkRPAREN === tk
  end

  name
end
            
get_symbol_or_name() click to toggle source

Extracts a name or symbol from the token stream.

 
               # File rdoc/parser/ruby.rb, line 376
def get_symbol_or_name
  tk = get_tk
  case tk
  when TkSYMBOL then
    text = tk.text.sub(/^:/, '')

    if TkASSIGN === peek_tk then
      get_tk
      text << '='
    end

    text
  when TkId, TkOp then
    tk.name
  when TkAMPER,
       TkDSTRING,
       TkSTAR,
       TkSTRING then
    tk.text
  else
    raise RDoc::Error, "Name or symbol expected (got #{tk})"
  end
end
            
look_for_directives_in(context, comment) click to toggle source

Look for directives in a normal comment block:

# :stopdoc:
# Don't display comment from this point forward

This routine modifies its comment parameter.

 
               # File rdoc/parser/ruby.rb, line 408
def look_for_directives_in context, comment
  @preprocess.handle comment, context do |directive, param|
    case directive
    when 'method', 'singleton-method',
         'attr', 'attr_accessor', 'attr_reader', 'attr_writer' then
      false # handled elsewhere
    when 'section' then
      context.set_current_section param, comment
      comment.replace ''
      break
    end
  end

  remove_private_comments comment
end
            
make_message(message) click to toggle source

Adds useful info about the parser to message

 
               # File rdoc/parser/ruby.rb, line 427
def make_message message
  prefix = "#{@file_name}:"

  prefix << "#{@scanner.line_no}:#{@scanner.char_no}:" if @scanner

  "#{prefix} #{message}"
end
            
parse_alias(context, single, tk, comment) click to toggle source

Parses an alias in context with comment

 
               # File rdoc/parser/ruby.rb, line 510
def parse_alias(context, single, tk, comment)
  offset  = tk.seek
  line_no = tk.line_no

  skip_tkspace

  if TkLPAREN === peek_tk then
    get_tk
    skip_tkspace
  end

  new_name = get_symbol_or_name

  @scanner.instance_eval { @lex_state = EXPR_FNAME }

  skip_tkspace
  if TkCOMMA === peek_tk then
    get_tk
    skip_tkspace
  end

  begin
    old_name = get_symbol_or_name
  rescue RDoc::Error
    return
  end

  al = RDoc::Alias.new(get_tkread, old_name, new_name, comment,
                       single == SINGLE)
  al.record_location @top_level
  al.offset = offset
  al.line   = line_no

  read_documentation_modifiers al, RDoc::ATTR_MODIFIERS
  context.add_alias al
  @stats.add_alias al

  al
end
            
parse_attr(context, single, tk, comment) click to toggle source

Creates an RDoc::Attr for the name following tk, setting the comment to comment.

 
               # File rdoc/parser/ruby.rb, line 439
def parse_attr(context, single, tk, comment)
  offset  = tk.seek
  line_no = tk.line_no

  args = parse_symbol_arg 1
  if args.size > 0 then
    name = args[0]
    rw = "R"
    skip_tkspace false
    tk = get_tk

    if TkCOMMA === tk then
      rw = "RW" if get_bool
    else
      unget_tk tk
    end

    att = RDoc::Attr.new get_tkread, name, rw, comment, single == SINGLE
    att.record_location @top_level
    att.offset = offset
    att.line   = line_no

    read_documentation_modifiers att, RDoc::ATTR_MODIFIERS

    context.add_attribute att

    @stats.add_attribute att
  else
    warn "'attr' ignored - looks like a variable"
  end
end
            
parse_attr_accessor(context, single, tk, comment) click to toggle source

Creates an RDoc::Attr for each attribute listed after tk, setting the comment for each to comment.

 
               # File rdoc/parser/ruby.rb, line 475
def parse_attr_accessor(context, single, tk, comment)
  offset  = tk.seek
  line_no = tk.line_no

  args = parse_symbol_arg
  rw = "?"

  tmp = RDoc::CodeObject.new
  read_documentation_modifiers tmp, RDoc::ATTR_MODIFIERS
  # TODO In most other places we let the context keep track of document_self
  # and add found items appropriately but here we do not.  I'm not sure why.
  return unless tmp.document_self

  case tk.name
  when "attr_reader"   then rw = "R"
  when "attr_writer"   then rw = "W"
  when "attr_accessor" then rw = "RW"
  else
    rw = '?'
  end

  for name in args
    att = RDoc::Attr.new get_tkread, name, rw, comment, single == SINGLE
    att.record_location @top_level
    att.offset = offset
    att.line   = line_no

    context.add_attribute att
    @stats.add_attribute att
  end
end
            
parse_call_parameters(tk) click to toggle source

Extracts call parameters from the token stream.

 
               # File rdoc/parser/ruby.rb, line 553
def parse_call_parameters(tk)
  end_token = case tk
              when TkLPAREN, TkfLPAREN
                TkRPAREN
              when TkRPAREN
                return ""
              else
                TkNL
              end
  nest = 0

  loop do
    case tk
    when TkSEMICOLON
      break
    when TkLPAREN, TkfLPAREN
      nest += 1
    when end_token
      if end_token == TkRPAREN
        nest -= 1
        break if @scanner.lex_state == EXPR_END and nest <= 0
      else
        break unless @scanner.continue
      end
    when TkCOMMENT, TkASSIGN, TkOPASGN
      unget_tk(tk)
      break
    when nil then
      break
    end
    tk = get_tk
  end
  res = get_tkread.tr("\n", " ").strip
  res = "" if res == ";"
  res
end
            
parse_class(container, single, tk, comment) click to toggle source

Parses a class in context with comment

 
               # File rdoc/parser/ruby.rb, line 593
def parse_class(container, single, tk, comment)
  offset  = tk.seek
  line_no = tk.line_no

  declaration_context = container
  container, name_t, given_name = get_class_or_module container

  case name_t
  when TkCONSTANT
    name = name_t.name
    superclass = '::Object'

    if TkLT === peek_tk then
      get_tk
      skip_tkspace
      superclass = get_class_specification
      superclass = '(unknown)' if superclass.empty?
    end

    cls_type = single == SINGLE ? RDoc::SingleClass : RDoc::NormalClass
    cls = declaration_context.add_class cls_type, given_name, superclass
    cls.ignore unless container.document_children

    read_documentation_modifiers cls, RDoc::CLASS_MODIFIERS
    cls.record_location @top_level
    cls.offset = offset
    cls.line   = line_no

    cls.add_comment comment, @top_level

    @top_level.add_to_classes_or_modules cls
    @stats.add_class cls

    parse_statements cls
  when TkLSHFT
    case name = get_class_specification
    when "self", container.name
      parse_statements container, SINGLE
    else
      other = RDoc::TopLevel.find_class_named name

      unless other then
        other = container.add_module RDoc::NormalModule, name
        other.record_location @top_level
        other.offset  = offset
        other.line    = line_no

        other.add_comment comment, @top_level
      end

      # notify :nodoc: all if not a constant-named class/module
      # (and remove any comment)
      unless name =~ /\A(::)?[A-Z]/ then
        other.document_self = nil
        other.document_children = false
        other.clear_comment
      end

      @top_level.add_to_classes_or_modules other
      @stats.add_class other

      read_documentation_modifiers other, RDoc::CLASS_MODIFIERS
      parse_statements(other, SINGLE)
    end
  else
    warn("Expected class name or '<<'. Got #{name_t.class}: #{name_t.text.inspect}")
  end
end
            
parse_comment(container, tk, comment) click to toggle source

Generates an RDoc::Method or RDoc::Attr from comment by looking for :method: or :attr: directives in comment.

 
               # File rdoc/parser/ruby.rb, line 754
def parse_comment(container, tk, comment)
  column  = tk.char_no
  offset  = tk.seek
  line_no = tk.line_no

  singleton = !!comment.sub!(/(^# +:?)(singleton-)(method:)/, '\1\3')

  # REFACTOR
  if comment.sub!(/^# +:?method: *(\S*).*?\n/i, '') then
    name = $1 unless $1.empty?

    meth = RDoc::GhostMethod.new get_tkread, name
    meth.record_location @top_level
    meth.singleton = singleton
    meth.offset    = offset
    meth.line      = line_no

    meth.start_collecting_tokens
    indent = TkSPACE.new nil, 1, 1
    indent.set_text " " * column

    position_comment = TkCOMMENT.new nil, line_no, 1
    position_comment.set_text "# File #{@top_level.absolute_name}, line #{line_no}"
    meth.add_tokens [position_comment, NEWLINE_TOKEN, indent]

    meth.params = ''

    extract_call_seq comment, meth

    return unless meth.name

    container.add_method meth

    meth.comment = comment

    @stats.add_method meth
  elsif comment.sub!(/# +:?(attr(_reader|_writer|_accessor)?): *(\S*).*?\n/i, '') then
    rw = case $1
         when 'attr_reader' then 'R'
         when 'attr_writer' then 'W'
         else 'RW'
         end

    name = $3 unless $3.empty?

    # TODO authorize 'singleton-attr...'?
    att = RDoc::Attr.new get_tkread, name, rw, comment
    att.record_location @top_level
    att.offset    = offset
    att.line      = line_no

    container.add_attribute att
    @stats.add_attribute att
  end

  true
end
            
parse_constant(container, tk, comment) click to toggle source

Parses a constant in context with comment

 
               # File rdoc/parser/ruby.rb, line 665
def parse_constant container, tk, comment
  offset  = tk.seek
  line_no = tk.line_no

  name = tk.name
  skip_tkspace false

  return unless name =~ /^\w+$/

  eq_tk = get_tk

  unless TkASSIGN === eq_tk then
    unget_tk eq_tk
    return false
  end

  nest = 0
  get_tkread

  tk = get_tk

  if TkGT === tk then
    unget_tk tk
    unget_tk eq_tk
    return false
  end

  rhs_name = ''

  loop do
    case tk
    when TkSEMICOLON then
      break if nest <= 0
    when TkLPAREN, TkfLPAREN, TkLBRACE, TkfLBRACE, TkLBRACK, TkfLBRACK,
         TkDO, TkIF, TkUNLESS, TkCASE, TkDEF, TkBEGIN then
      nest += 1
    when TkRPAREN, TkRBRACE, TkRBRACK, TkEND then
      nest -= 1
    when TkCOMMENT then
      if nest <= 0 &&
         (@scanner.lex_state == EXPR_END || !@scanner.continue) then
        unget_tk tk
        break
      end
    when TkCONSTANT then
      rhs_name << tk.name

      if nest <= 0 and TkNL === peek_tk then
        mod = if rhs_name =~ /^::/ then
                RDoc::TopLevel.find_class_or_module rhs_name
              else
                container.find_module_named rhs_name
              end

        container.add_module_alias mod, name, @top_level if mod
        break
      end
    when TkNL then
      if nest <= 0 &&
         (@scanner.lex_state == EXPR_END || !@scanner.continue) then
        unget_tk tk
        break
      end
    when TkCOLON2, TkCOLON3 then
      rhs_name << '::'
    when nil then
      break
    end
    tk = get_tk
  end

  res = get_tkread.gsub(/^[ \t]+/, '').strip
  res = "" if res == ";"

  con = RDoc::Constant.new name, res, comment
  con.record_location @top_level
  con.offset = offset
  con.line   = line_no
  read_documentation_modifiers con, RDoc::CONSTANT_MODIFIERS

  @stats.add_constant con
  container.add_constant con
  true
end
            
parse_include(context, comment) click to toggle source

Parses an include in context with comment

 
               # File rdoc/parser/ruby.rb, line 815
def parse_include context, comment
  loop do
    skip_tkspace_comment

    name = get_constant_with_optional_parens

    unless name.empty? then
      incl = context.add_include RDoc::Include.new(name, comment)
      incl.record_location @top_level
    end

    return unless TkCOMMA === peek_tk

    get_tk
  end
end
            
parse_meta_attr(context, single, tk, comment) click to toggle source

Parses a meta-programmed attribute and creates an RDoc::Attr.

To create foo and bar attributes on class C with comment “My attributes”:

class C

  ##
  # :attr:
  #
  # My attributes

  my_attr :foo, :bar

end

To create a foo attribute on class C with comment “My attribute”:

class C

  ##
  # :attr: foo
  #
  # My attribute

  my_attr :foo, :bar

end
 
               # File rdoc/parser/ruby.rb, line 861
def parse_meta_attr(context, single, tk, comment)
  args = parse_symbol_arg
  rw = "?"

  # If nodoc is given, don't document any of them

  tmp = RDoc::CodeObject.new
  read_documentation_modifiers tmp, RDoc::ATTR_MODIFIERS

  if comment.sub!(/^# +:?(attr(_reader|_writer|_accessor)?): *(\S*).*?\n/i, '') then
    rw = case $1
         when 'attr_reader' then 'R'
         when 'attr_writer' then 'W'
         else 'RW'
         end
    name = $3 unless $3.empty?
  end

  if name then
    att = RDoc::Attr.new get_tkread, name, rw, comment, single == SINGLE
    att.record_location @top_level

    context.add_attribute att
    @stats.add_attribute att
  else
    args.each do |attr_name|
      att = RDoc::Attr.new(get_tkread, attr_name, rw, comment,
                           single == SINGLE)
      att.record_location @top_level

      context.add_attribute att
      @stats.add_attribute att
    end
  end
end
            
parse_meta_method(container, single, tk, comment) click to toggle source

Parses a meta-programmed method

 
               # File rdoc/parser/ruby.rb, line 900
def parse_meta_method(container, single, tk, comment)
  column  = tk.char_no
  offset  = tk.seek
  line_no = tk.line_no

  start_collecting_tokens
  add_token tk
  add_token_listener self

  skip_tkspace false

  singleton = !!comment.sub!(/(^# +:?)(singleton-)(method:)/, '\1\3')

  if comment.sub!(/^# +:?method: *(\S*).*?\n/i, '') then
    name = $1 unless $1.empty?
  end

  if name.nil? then
    name_t = get_tk
    case name_t
    when TkSYMBOL then
      name = name_t.text[1..-1]
    when TkSTRING then
      name = name_t.value[1..-2]
    when TkASSIGN then # ignore
      remove_token_listener self
      return
    else
      warn "unknown name token #{name_t.inspect} for meta-method '#{tk.name}'"
      name = 'unknown'
    end
  end

  meth = RDoc::MetaMethod.new get_tkread, name
  meth.record_location @top_level
  meth.offset = offset
  meth.line   = line_no
  meth.singleton = singleton

  remove_token_listener self

  meth.start_collecting_tokens
  indent = TkSPACE.new nil, 1, 1
  indent.set_text " " * column

  position_comment = TkCOMMENT.new nil, line_no, 1
  position_comment.value = "# File #{@top_level.absolute_name}, line #{line_no}"
  meth.add_tokens [position_comment, NEWLINE_TOKEN, indent]
  meth.add_tokens @token_stream

  token_listener meth do
    meth.params = ''

    extract_call_seq comment, meth

    container.add_method meth

    last_tk = tk

    while tk = get_tk do
      case tk
      when TkSEMICOLON then
        break
      when TkNL then
        break unless last_tk and TkCOMMA === last_tk
      when TkSPACE then
        # expression continues
      when TkDO then
        unget_tk tk
        parse_statements container, single, meth
        break
      else
        last_tk = tk
      end
    end
  end

  meth.comment = comment

  @stats.add_method meth
end
            
parse_method(container, single, tk, comment) click to toggle source

Parses a normal method defined by def

 
               # File rdoc/parser/ruby.rb, line 985
def parse_method(container, single, tk, comment)
  added_container = nil
  meth = nil
  name = nil
  column  = tk.char_no
  offset  = tk.seek
  line_no = tk.line_no

  start_collecting_tokens
  add_token tk

  token_listener self do
    @scanner.instance_eval do @lex_state = EXPR_FNAME end

    skip_tkspace
    name_t = get_tk
    back_tk = skip_tkspace
    meth = nil
    added_container = false

    dot = get_tk
    if TkDOT === dot or TkCOLON2 === dot then
      @scanner.instance_eval do @lex_state = EXPR_FNAME end
      skip_tkspace
      name_t2 = get_tk

      case name_t
      when TkSELF, TkMOD then
        name = name_t2.name
      when TkCONSTANT then
        name = name_t2.name
        prev_container = container
        container = container.find_module_named(name_t.name)
        unless container then
          added_container = true
          obj = name_t.name.split("::").inject(Object) do |state, item|
            state.const_get(item)
          end rescue nil

          type = obj.class == Class ? RDoc::NormalClass : RDoc::NormalModule

          unless [Class, Module].include?(obj.class) then
            warn("Couldn't find #{name_t.name}. Assuming it's a module")
          end

          if type == RDoc::NormalClass then
            sclass = obj.superclass ? obj.superclass.name : nil
            container = prev_container.add_class type, name_t.name, sclass
          else
            container = prev_container.add_module type, name_t.name
          end

          container.record_location @top_level
        end
      when TkIDENTIFIER, TkIVAR, TkGVAR then
        dummy = RDoc::Context.new
        dummy.parent = container
        skip_method dummy
        return
      when TkTRUE, TkFALSE, TkNIL then
        klass_name = "#{name_t.name.capitalize}Class"
        container = RDoc::TopLevel.find_class_named klass_name
        container ||= @top_level.add_class RDoc::NormalClass, klass_name

        name = name_t2.name
      else
        warn "unexpected method name token #{name_t.inspect}"
        # break
        skip_method container
        return
      end

      meth = RDoc::AnyMethod.new(get_tkread, name)
      meth.singleton = true
    else
      unget_tk dot
      back_tk.reverse_each do |token|
        unget_tk token
      end

      name = case name_t
             when TkSTAR, TkAMPER then
               name_t.text
             else
               unless name_t.respond_to? :name then
                 warn "expected method name token, . or ::, got #{name_t.inspect}"
                 skip_method container
                 return
               end
               name_t.name
             end

      meth = RDoc::AnyMethod.new get_tkread, name
      meth.singleton = (single == SINGLE)
    end
  end

  meth.record_location @top_level
  meth.offset = offset
  meth.line   = line_no

  meth.start_collecting_tokens
  indent = TkSPACE.new nil, 1, 1
  indent.set_text " " * column

  token = TkCOMMENT.new nil, line_no, 1
  token.set_text "# File #{@top_level.absolute_name}, line #{line_no}"
  meth.add_tokens [token, NEWLINE_TOKEN, indent]
  meth.add_tokens @token_stream

  token_listener meth do
    @scanner.instance_eval do @continue = false end
    parse_method_parameters meth

    if meth.document_self then
      container.add_method meth
    elsif added_container then
      container.document_self = false
    end

    # Having now read the method parameters and documentation modifiers, we
    # now know whether we have to rename #initialize to ::new

    if name == "initialize" && !meth.singleton then
      if meth.dont_rename_initialize then
        meth.visibility = :protected
      else
        meth.singleton = true
        meth.name = "new"
        meth.visibility = :public
      end
    end

    parse_statements container, single, meth
  end

  extract_call_seq comment, meth

  meth.comment = comment

  @stats.add_method meth
end
            
parse_method_or_yield_parameters(method = nil, modifiers = RDoc::METHOD_MODIFIERS) click to toggle source

Extracts yield parameters from method

 
               # File rdoc/parser/ruby.rb, line 1131
def parse_method_or_yield_parameters(method = nil,
                                     modifiers = RDoc::METHOD_MODIFIERS)
  skip_tkspace false
  tk = get_tk

  # Little hack going on here. In the statement
  #  f = 2*(1+yield)
  # We see the RPAREN as the next token, so we need
  # to exit early. This still won't catch all cases
  # (such as "a = yield + 1"
  end_token = case tk
              when TkLPAREN, TkfLPAREN
                TkRPAREN
              when TkRPAREN
                return ""
              else
                TkNL
              end
  nest = 0

  loop do
    case tk
    when TkSEMICOLON then
      break if nest == 0
    when TkLBRACE, TkfLBRACE then
      nest += 1
    when TkRBRACE then
      nest -= 1
      if nest <= 0
        # we might have a.each { |i| yield i }
        unget_tk(tk) if nest < 0
        break
      end
    when TkLPAREN, TkfLPAREN then
      nest += 1
    when end_token then
      if end_token == TkRPAREN
        nest -= 1
        break if @scanner.lex_state == EXPR_END and nest <= 0
      else
        break unless @scanner.continue
      end
    when TkRPAREN then
      nest -= 1
    when method && method.block_params.nil? && TkCOMMENT then
      unget_tk tk
      read_documentation_modifiers method, modifiers
      @read.pop
    when TkCOMMENT then
      @read.pop
    when nil then
      break
    end
    tk = get_tk
  end

  res = get_tkread.gsub(/\s+/, ' ').strip
  res = '' if res == ';'
  res
end
            
parse_method_parameters(method) click to toggle source

Capture the method’s parameters. Along the way, look for a comment containing:

# yields: ....

and add this as the block_params for the method

 
               # File rdoc/parser/ruby.rb, line 1200
def parse_method_parameters(method)
  res = parse_method_or_yield_parameters method

  res = "(#{res})" unless res =~ /\A\(/
  method.params = res unless method.params

  if method.block_params.nil? then
    skip_tkspace false
    read_documentation_modifiers method, RDoc::METHOD_MODIFIERS
  end
end
            
parse_module(container, single, tk, comment) click to toggle source

Parses an RDoc::NormalModule in container with comment

 
               # File rdoc/parser/ruby.rb, line 1215
def parse_module(container, single, tk, comment)
  container, name_t, = get_class_or_module container

  name = name_t.name

  mod = container.add_module RDoc::NormalModule, name
  mod.record_location @top_level

  read_documentation_modifiers mod, RDoc::CLASS_MODIFIERS
  mod.add_comment comment, @top_level
  parse_statements(mod)

  @top_level.add_to_classes_or_modules mod
  @stats.add_module mod
end
            
parse_require(context, comment) click to toggle source

Parses an RDoc::Require in context containing comment

 
               # File rdoc/parser/ruby.rb, line 1234
def parse_require(context, comment)
  skip_tkspace_comment
  tk = get_tk

  if TkLPAREN === tk then
    skip_tkspace_comment
    tk = get_tk
  end

  name = tk.text if TkSTRING === tk

  if name then
    @top_level.add_require RDoc::Require.new(name, comment)
  else
    unget_tk tk
  end
end
            
parse_statements(container, single = NORMAL, current_method = nil, comment = '') click to toggle source

The core of the ruby parser.

 
               # File rdoc/parser/ruby.rb, line 1255
def parse_statements(container, single = NORMAL, current_method = nil,
                     comment = '')
  comment.force_encoding @encoding if @encoding

  nest = 1
  save_visibility = container.visibility

  non_comment_seen = true

  while tk = get_tk do
    keep_comment = false
    try_parse_comment = false

    non_comment_seen = true unless TkCOMMENT === tk

    case tk
    when TkNL then
      skip_tkspace
      tk = get_tk

      if TkCOMMENT === tk then
        if non_comment_seen then
          # Look for RDoc in a comment about to be thrown away
          non_comment_seen = parse_comment container, tk, comment unless
            comment.empty?

          comment = ''
          comment.force_encoding @encoding if @encoding
        end

        while TkCOMMENT === tk do
          comment << tk.text << "\n"

          tk = get_tk

          if TkNL === tk then
            skip_tkspace false # leading spaces
            tk = get_tk
          end
        end

        unless comment.empty? then
          look_for_directives_in container, comment

          if container.done_documenting then
            container.ongoing_visibility = save_visibility
          end
        end

        keep_comment = true
      else
        non_comment_seen = true
      end

      unget_tk tk # TODO peek instead of get then unget
      keep_comment = true

    when TkCLASS then
      parse_class container, single, tk, comment

    when TkMODULE then
      if container.document_children then
        parse_module container, single, tk, comment
      else
        nest += 1
      end

    when TkDEF then
      parse_method container, single, tk, comment

    when TkCONSTANT then
      unless parse_constant container, tk, comment then
        try_parse_comment = true
      end

    when TkALIAS then
      parse_alias container, single, tk, comment unless current_method

    when TkYIELD then
      if current_method.nil? then
        warn "Warning: yield outside of method" if container.document_self
      else
        parse_yield container, single, tk, current_method
      end

    # Until and While can have a 'do', which shouldn't increase the nesting.
    # We can't solve the general case, but we can handle most occurrences by
    # ignoring a do at the end of a line.

    when TkUNTIL, TkWHILE then
      nest += 1
      skip_optional_do_after_expression

    # 'for' is trickier
    when TkFOR then
      nest += 1
      skip_for_variable
      skip_optional_do_after_expression

    when TkCASE, TkDO, TkIF, TkUNLESS, TkBEGIN then
      nest += 1

    when TkIDENTIFIER then
      if nest == 1 and current_method.nil? then
        case tk.name
        when 'private', 'protected', 'public', 'private_class_method',
             'public_class_method', 'module_function' then
          parse_visibility container, single, tk
          keep_comment = true
        when 'attr' then
          parse_attr container, single, tk, comment
        when /^attr_(reader|writer|accessor)$/ then
          parse_attr_accessor container, single, tk, comment
        when 'alias_method' then
          parse_alias container, single, tk, comment
        when 'require', 'include' then
          # ignore
        else
          if comment =~ /\A#\#$/ then
            case comment
            when /^# +:?attr(_reader|_writer|_accessor)?:/ then
              parse_meta_attr container, single, tk, comment
            else
              parse_meta_method container, single, tk, comment
            end
          end
        end
      end

      case tk.name
      when "require" then
        parse_require container, comment
      when "include" then
        parse_include container, comment
      end

    when TkEND then
      nest -= 1
      if nest == 0 then
        read_documentation_modifiers container, RDoc::CLASS_MODIFIERS
        container.ongoing_visibility = save_visibility

        parse_comment container, tk, comment unless comment.empty?

        return
      end
    else
      try_parse_comment = nest == 1
    end

    if try_parse_comment then
      non_comment_seen = parse_comment container, tk, comment unless
        comment.empty?

      keep_comment = false
    end

    unless keep_comment then
      comment = ''
      comment.force_encoding @encoding if @encoding
    end

    begin
      get_tkread
      skip_tkspace false
    end while peek_tk == TkNL
  end
end
            
parse_symbol_arg(no = nil) click to toggle source

Parse up to no symbol arguments

 
               # File rdoc/parser/ruby.rb, line 1427
def parse_symbol_arg(no = nil)
  args = []

  skip_tkspace_comment

  case tk = get_tk
  when TkLPAREN
    loop do
      skip_tkspace_comment
      if tk1 = parse_symbol_in_arg
        args.push tk1
        break if no and args.size >= no
      end

      skip_tkspace_comment
      case tk2 = get_tk
      when TkRPAREN
        break
      when TkCOMMA
      else
        warn("unexpected token: '#{tk2.inspect}'") if $DEBUG_RDOC
        break
      end
    end
  else
    unget_tk tk
    if tk = parse_symbol_in_arg
      args.push tk
      return args if no and args.size >= no
    end

    loop do
      skip_tkspace false

      tk1 = get_tk
      unless TkCOMMA === tk1 then
        unget_tk tk1
        break
      end

      skip_tkspace_comment
      if tk = parse_symbol_in_arg
        args.push tk
        break if no and args.size >= no
      end
    end
  end

  args
end
            
parse_symbol_in_arg() click to toggle source

Returns symbol text from the next token

 
               # File rdoc/parser/ruby.rb, line 1481
def parse_symbol_in_arg
  case tk = get_tk
  when TkSYMBOL
    tk.text.sub(/^:/, '')
  when TkSTRING
    eval @read[-1]
  when TkDSTRING, TkIDENTIFIER then
    nil # ignore
  else
    warn("Expected symbol or string, got #{tk.inspect}") if $DEBUG_RDOC
    nil
  end
end
            
parse_top_level_statements(container) click to toggle source

Parses statements in the top-level container

 
               # File rdoc/parser/ruby.rb, line 1498
def parse_top_level_statements container
  comment = collect_first_comment
  look_for_directives_in container, comment

  # HACK move if to RDoc::Context#comment=
  container.comment = comment if container.document_self unless comment.empty?

  parse_statements container, NORMAL, nil, comment
end
            
parse_visibility(container, single, tk) click to toggle source

Determines the visibility in container from tk

 
               # File rdoc/parser/ruby.rb, line 1511
def parse_visibility(container, single, tk)
  singleton = (single == SINGLE)

  vis_type = tk.name

  vis = case vis_type
        when 'private'   then :private
        when 'protected' then :protected
        when 'public'    then :public
        when 'private_class_method' then
          singleton = true
          :private
        when 'public_class_method' then
          singleton = true
          :public
        when 'module_function' then
          singleton = true
          :public
        else
          raise RDoc::Error, "Invalid visibility: #{tk.name}"
        end

  skip_tkspace_comment false

  case peek_tk
    # Ryan Davis suggested the extension to ignore modifiers, because he
    # often writes
    #
    #   protected unless $TESTING
    #
  when TkNL, TkUNLESS_MOD, TkIF_MOD, TkSEMICOLON then
    container.ongoing_visibility = vis
  else
    new_methods = []

    case vis_type
    when 'module_function' then
      args = parse_symbol_arg
      container.set_visibility_for args, :private, false

      container.methods_matching args do |m|
        s_m = m.dup
        s_m.record_location @top_level
        s_m.singleton = true
        new_methods << s_m
      end
    when 'public_class_method', 'private_class_method' then
      args = parse_symbol_arg

      container.methods_matching args, true do |m|
        if m.parent != container then
          m = m.dup
          m.record_location @top_level
          new_methods << m
        end

        m.visibility = vis
      end
    else
      args = parse_symbol_arg
      container.set_visibility_for args, vis, singleton
    end

    new_methods.each do |method|
      case method
      when RDoc::AnyMethod then
        container.add_method method
      when RDoc::Attr then
        container.add_attribute method
      end
      method.visibility = vis
    end
  end
end
            
parse_yield(context, single, tk, method) click to toggle source

Determines the block parameter for context

 
               # File rdoc/parser/ruby.rb, line 1589
def parse_yield(context, single, tk, method)
  return if method.block_params

  get_tkread
  @scanner.instance_eval { @continue = false }
  method.block_params = parse_method_or_yield_parameters
end
            
read_directive(allowed) click to toggle source

Directives are modifier comments that can appear after class, module, or method names. For example:

def fred # :yields: a, b

or:

class MyClass # :nodoc:

We return the directive name and any parameters as a two element array

 
               # File rdoc/parser/ruby.rb, line 1609
def read_directive allowed
  tk = get_tk

  if TkCOMMENT === tk then
    return unless tk.text =~ /\s*:?(\w+):\s*(.*)/

    directive = $1.downcase

    return [directive, $2] if allowed.include? directive
  else
    unget_tk tk
  end
end
            
read_documentation_modifiers(context, allow) click to toggle source

Handles the directive for context if the directive is listed in allow. This method is called for directives following a definition.

 
               # File rdoc/parser/ruby.rb, line 1627
def read_documentation_modifiers context, allow
  directive, value = read_directive allow

  return unless directive

  @preprocess.handle_directive '', directive, value, context do |dir, param|
    if %w[notnew not_new not-new].include? dir then
      context.dont_rename_initialize = true

      true
    end
  end
end
            
remove_private_comments(comment) click to toggle source

Removes private comments from comment

 
               # File rdoc/parser/ruby.rb, line 1644
def remove_private_comments(comment)
  empty = ''
  empty.force_encoding comment.encoding if Object.const_defined? :Encoding

  comment.gsub!(/^#--.*?^#\+\+\n?/m, empty)
  comment.sub!(/^#--.*/m, '')
end
            
scan() click to toggle source

Scans this ruby file for ruby constructs

 
               # File rdoc/parser/ruby.rb, line 1655
  def scan
    reset

    catch :eof do
      begin
        parse_top_level_statements @top_level
      rescue StandardError => e
        bytes = ''

        20.times do @scanner.ungetc end
        count = 0
        60.times do |i|
          count = i
          byte = @scanner.getc
          break unless byte
          bytes << byte
        end
        count -= 20
        count.times do @scanner.ungetc end

        $stderr.puts <<-EOF

#{self.class} failure around line #{@scanner.line_no} of
#{@file_name}

        EOF

        unless bytes.empty? then
          $stderr.puts
          $stderr.puts bytes.inspect
        end

        raise e
      end
    end

    @top_level
  end
            
skip_for_variable() click to toggle source

skip the var [in] part of a ‘for’ statement

 
               # File rdoc/parser/ruby.rb, line 1744
def skip_for_variable
  skip_tkspace false
  tk = get_tk
  skip_tkspace false
  tk = get_tk
  unget_tk(tk) unless TkIN === tk
end
            
skip_method(container) click to toggle source

Skips the next method in container

 
               # File rdoc/parser/ruby.rb, line 1755
def skip_method container
  meth = RDoc::AnyMethod.new "", "anon"
  parse_method_parameters meth
  parse_statements container, false, meth
end
            
skip_optional_do_after_expression() click to toggle source

while, until, and for have an optional do

 
               # File rdoc/parser/ruby.rb, line 1697
def skip_optional_do_after_expression
  skip_tkspace false
  tk = get_tk
  case tk
  when TkLPAREN, TkfLPAREN then
    end_token = TkRPAREN
  else
    end_token = TkNL
  end

  b_nest = 0
  nest = 0
  @scanner.instance_eval { @continue = false }

  loop do
    case tk
    when TkSEMICOLON then
      break if b_nest.zero?
    when TkLPAREN, TkfLPAREN then
      nest += 1
    when TkBEGIN then
      b_nest += 1
    when TkEND then
      b_nest -= 1
    when TkDO
      break if nest.zero?
    when end_token then
      if end_token == TkRPAREN
        nest -= 1
        break if @scanner.lex_state == EXPR_END and nest.zero?
      else
        break unless @scanner.continue
      end
    when nil then
      break
    end
    tk = get_tk
  end

  skip_tkspace false

  get_tk if TkDO === peek_tk
end
            
skip_tkspace_comment(skip_nl = true) click to toggle source

Skip spaces until a comment is found

 
               # File rdoc/parser/ruby.rb, line 1764
def skip_tkspace_comment(skip_nl = true)
  loop do
    skip_tkspace skip_nl
    return unless TkCOMMENT === peek_tk
    get_tk
  end
end
            
warn(msg) click to toggle source

Prints msg to +$stderr+ unless we’re being quiet

 
               # File rdoc/parser/ruby.rb, line 1775
def warn(msg)
  return if @options.quiet
  msg = make_message msg
  $stderr.puts msg
end
            

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