require "rdoc/parsers/parse_simple"
module RDoc
# A parser is simple a class that implements
#
# #initialize(file_name, body, options)
#
# and
#
# #scan
#
# The initialize method takes a file name to be used, the body of the
# file, and an RDoc::Options object. The scan method is then called
# to return an appropriately parsed TopLevel code object.
#
# The ParseFactory is used to redirect to the correct parser given a filename
# extension. This magic works because individual parsers have to register
# themselves with us as they are loaded in. The do this using the following
# incantation
#
#
# require "rdoc/parsers/parsefactory"
#
# module RDoc
#
# class XyzParser
# extend ParseFactory <<<<
# parse_files_matching /\.xyz$/ <<<<
#
# def initialize(file_name, body, options)
# ...
# end
#
# def scan
# ...
# end
# end
# end
#
# Just to make life interesting, if we suspect a plain text file, we
# also look for a shebang line just in case it's a potential
# shell script
module ParserFactory
@@parsers = []
Parsers = Struct.new(:regexp, :parser)
# Record the fact that a particular class parses files that
# match a given extension
def parse_files_matching(regexp)
@@parsers.unshift Parsers.new(regexp, self)
end
# Return a parser that can handle a particular extension
def ParserFactory.can_parse(file_name)
@@parsers.find {|p| p.regexp.match(file_name) }
end
# Alias an extension to another extension. After this call,
# files ending "new_ext" will be parsed using the same parser
# as "old_ext"
def ParserFactory.alias_extension(old_ext, new_ext)
parser = ParserFactory.can_parse("xxx.#{old_ext}")
return false unless parser
@@parsers.unshift Parsers.new(Regexp.new("\\.#{new_ext}$"), parser.parser)
true
end
# Find the correct parser for a particular file name. Return a
# SimpleParser for ones that we don't know
def ParserFactory.parser_for(top_level, file_name, body, options, stats)
# If no extension, look for shebang
if file_name !~ /\.\w+$/ && body =~ %r{\A#!(.+)}
shebang = $1
case shebang
when %r{env\s+ruby}, %r{/ruby}
file_name = "dummy.rb"
end
end
parser_description = can_parse(file_name)
if parser_description
parser = parser_description.parser
else
parser = SimpleParser
end
parser.new(top_level, file_name, body, options, stats)
end
end
end
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