Skip to content
This repository
tree: 1cc8ab865f
Fetching contributors…

Cannot retrieve contributors at this time

file 166 lines (140 sloc) 5.457 kb
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166
require 'singleton'

# The Inflector transforms words from singular to plural, class names to table names, modularized class names to ones without,
# and class names to foreign keys. The default inflections for pluralization, singularization, and uncountable words are kept
# in inflections.rb.
module Inflector
  # A singleton instance of this class is yielded by Inflector.inflections, which can then be used to specify additional
  # inflection rules. Examples:
  #
  # Inflector.inflections do |inflect|
  # inflect.plural /^(ox)$/i, '\1\2en'
  # inflect.singular /^(ox)en/i, '\1'
  #
  # inflect.irregular 'octopus', 'octopi'
  #
  # inflect.uncountable "equipment"
  # end
  #
  # New rules are added at the top. So in the example above, the irregular rule for octopus will now be the first of the
  # pluralization and singularization rules that is runs. This guarantees that your rules run before any of the rules that may
  # already have been loaded.
  class Inflections
    include Singleton
    
    attr_reader :plurals, :singulars, :uncountables
    
    def initialize
      @plurals, @singulars, @uncountables = [], [], []
    end
    
    # Specifies a new pluralization rule and its replacement. The rule can either be a string or a regular expression.
    # The replacement should always be a string that may include references to the matched data from the rule.
    def plural(rule, replacement)
      @plurals.insert(0, [rule, replacement])
    end
    
    # Specifies a new singularization rule and its replacement. The rule can either be a string or a regular expression.
    # The replacement should always be a string that may include references to the matched data from the rule.
    def singular(rule, replacement)
      @singulars.insert(0, [rule, replacement])
    end

    # Specifies a new irregular that applies to both pluralization and singularization at the same time. This can only be used
    # for strings, not regular expressions. You simply pass the irregular in singular and plural form.
    #
    # Examples:
    # irregular 'octopus', 'octopi'
    # irregular 'person', 'people'
    def irregular(singular, plural)
      plural(Regexp.new("(#{singular[0,1]})#{singular[1..-1]}$", "i"), '\1' + plural[1..-1])
      singular(Regexp.new("(#{plural[0,1]})#{plural[1..-1]}$", "i"), '\1' + singular[1..-1])
    end
    
    # Add uncountable words that shouldn't be attempted inflected.
    #
    # Examples:
    # uncountable "money"
    # uncountable "money", "information"
    # uncountable %w( money information rice )
    def uncountable(*words)
      (@uncountables << words).flatten!
    end
    
    # Clears the loaded inflections within a given scope (default is :all). Give the scope as a symbol of the inflection type,
    # the options are: :plurals, :singulars, :uncountables
    #
    # Examples:
    # clear :all
    # clear :plurals
    def clear(scope = :all)
      case scope
        when :all
          @plurals, @singulars, @uncountables = [], [], []
        else
          instance_variable_set "@#{scope}", []
      end
    end
  end

  extend self

  def inflections
    if block_given?
      yield Inflections.instance
    else
      Inflections.instance
    end
  end

  def pluralize(word)
    result = word.to_s.dup

    if inflections.uncountables.include?(result.downcase)
      result
    else
      inflections.plurals.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
      result
    end
  end

  def singularize(word)
    result = word.to_s.dup

    if inflections.uncountables.include?(result.downcase)
      result
    else
      inflections.singulars.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
      result
    end
  end

  def camelize(lower_case_and_underscored_word)
    lower_case_and_underscored_word.to_s.gsub(/\/(.?)/) { "::" + $1.upcase }.gsub(/(^|_)(.)/) { $2.upcase }
  end

  def titleize(word)
    humanize(underscore(word)).gsub(/\b([a-z])/) { $1.capitalize }
  end
  
  def underscore(camel_cased_word)
    camel_cased_word.to_s.gsub(/::/, '/').gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2').gsub(/([a-z\d])([A-Z])/,'\1_\2').downcase
  end

  def humanize(lower_case_and_underscored_word)
    lower_case_and_underscored_word.to_s.gsub(/_id$/, "").gsub(/_/, " ").capitalize
  end

  def demodulize(class_name_in_module)
    class_name_in_module.to_s.gsub(/^.*::/, '')
  end

  def tableize(class_name)
    pluralize(underscore(class_name))
  end
  
  def classify(table_name)
    camelize(singularize(table_name))
  end

  def foreign_key(class_name, separate_class_name_and_id_with_underscore = true)
    underscore(demodulize(class_name)) + (separate_class_name_and_id_with_underscore ? "_id" : "id")
  end

  def constantize(camel_cased_word)
    raise NameError, "#{camel_cased_word.inspect} is not a valid constant name!" unless
      camel_cased_word.split("::").all? { |part| /^[A-Z]\w*$/ =~ part }
    
    camel_cased_word = "::#{camel_cased_word}" unless camel_cased_word[0, 2] == '::'
    Object.module_eval(camel_cased_word, __FILE__, __LINE__)
  end

  def ordinalize(number)
    if (11..13).include?(number.to_i % 100)
      "#{number}th"
    else
      case number.to_i % 10
        when 1: "#{number}st"
        when 2: "#{number}nd"
        when 3: "#{number}rd"
        else "#{number}th"
      end
    end
  end
end

require File.dirname(__FILE__) + '/inflections'
Something went wrong with that request. Please try again.