free_mutant/lib/mutant/cli/classifier.rb
2013-06-14 21:12:10 +02:00

141 lines
2.8 KiB
Ruby

module Mutant
class CLI
# A classifier for input strings
class Classifier < Matcher
include AbstractType, Adamantium::Flat, Equalizer.new(:identification)
SCOPE_NAME_PATTERN = /[A-Za-z][A-Za-z_0-9]*/.freeze
METHOD_NAME_PATTERN = /[_A-Za-z][A-Za-z0-9_]*[!?=]?/.freeze
SCOPE_PATTERN = /(?:::)?#{SCOPE_NAME_PATTERN}(?:::#{SCOPE_NAME_PATTERN})*/.freeze
SINGLETON_PATTERN = %r(\A(#{SCOPE_PATTERN})\z).freeze
REGISTRY = []
# Register classifier
#
# @return [undefined]
#
# @api private
#
def self.register
REGISTRY << self
end
private_class_method :register
# Return constant
#
# @param [String] location
#
# @return [Class|Module]
#
# @api private
#
def self.constant_lookup(location)
location.gsub(%r(\A::), '').split('::').inject(::Object) do |parent, name|
parent.const_get(name)
end
end
# Return matchers for input
#
# @param [String] input
#
# @return [Classifier]
# if a classifier handles the input
#
# @return [nil]
# otherwise
#
# @api private
#
def self.build(input)
classifiers = REGISTRY.map do |descendant|
descendant.run(input)
end.compact
raise if classifiers.length > 1
classifiers.first
end
# Run classifier
#
# @return [Classifier]
# if input is handled by classifier
#
# @return [nil]
# otherwise
#
# @api private
#
def self.run(input)
match = self::REGEXP.match(input)
return unless match
new(match)
end
# No protected_class_method in ruby :(
class << self; protected :run; end
# Enumerate subjects
#
# @return [self]
# if block given
#
# @return [Enumerator<Subject>]
# otherwise
#
# @api private
#
def each(&block)
return to_enum unless block_given?
matcher.each(&block)
self
end
# Return identification
#
# @return [String]
#
# @api private
#
def identification
match.to_s
end
memoize :identification
private
# Initialize object
#
# @param [MatchData] match
#
# @return [undefined]
#
# @api private
#
def initialize(match)
@match = match
end
# Return match
#
# @return [MatchData]
#
# @api private
#
attr_reader :match
# Return matcher
#
# @return [Matcher]
#
# @api private
#
abstract_method :matcher
end # Classifier
end # CLI
end # Mutant