inflector.rb in activesupport-2.1.1

- old
+ new
@@ -1,306 +1,311 @@
 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.
-#
-# The Rails core team has stated patches for the inflections library will not be accepted
-# in order to avoid breaking legacy applications which may be relying on errant inflections.
-# If you discover an incorrect inflection and require it for your application, you'll need
-# to correct it yourself (explained below).
-module Inflector
-  # A singleton instance of this class is yielded by Inflector.inflections, which can then be used to specify additional
-  # inflection rules. Examples:
+module ActiveSupport
+  # 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.
   #
-  #   Inflector.inflections do |inflect|
-  #     inflect.plural /^(ox)$/i, '\1\2en'
-  #     inflect.singular /^(ox)en/i, '\1'
-  #
-  #     inflect.irregular 'octopus', 'octopi'
-  #
-  #     inflect.uncountable "equipment"
-  #   end
-  #
-  # New rules are added at the top. So in the example above, the irregular rule for octopus will now be the first of the
-  # pluralization and singularization rules that is runs. This guarantees that your rules run before any of the rules that may
-  # already have been loaded.
-  class Inflections
-    include Singleton
+  # The Rails core team has stated patches for the inflections library will not be accepted
+  # in order to avoid breaking legacy applications which may be relying on errant inflections.
+  # If you discover an incorrect inflection and require it for your application, you'll need
+  # to correct it yourself (explained below).
+  module Inflector
+    # A singleton instance of this class is yielded by Inflector.inflections, which can then be used to specify additional
+    # inflection rules. Examples:
+    #
+    #   Inflector.inflections do |inflect|
+    #     inflect.plural /^(ox)$/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
+      attr_reader :plurals, :singulars, :uncountables
 
-    def initialize
-      @plurals, @singulars, @uncountables = [], [], []
-    end
+      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])
+      # 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)
+        if singular[0,1].upcase == plural[0,1].upcase
+          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])
+        else
+          plural(Regexp.new("#{singular[0,1].upcase}(?i)#{singular[1..-1]}$"), plural[0,1].upcase + plural[1..-1])
+          plural(Regexp.new("#{singular[0,1].downcase}(?i)#{singular[1..-1]}$"), plural[0,1].downcase + plural[1..-1])
+          singular(Regexp.new("#{plural[0,1].upcase}(?i)#{plural[1..-1]}$"), singular[0,1].upcase + singular[1..-1])
+          singular(Regexp.new("#{plural[0,1].downcase}(?i)#{plural[1..-1]}$"), singular[0,1].downcase + singular[1..-1])
+        end
+      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 <tt>:all</tt>).
+      # Give the scope as a symbol of the inflection type, the options are: <tt>:plurals</tt>,
+      # <tt>:singulars</tt>, <tt>:uncountables</tt>.
+      #
+      # Examples:
+      #   clear :all
+      #   clear :plurals
+      def clear(scope = :all)
+        case scope
+          when :all
+            @plurals, @singulars, @uncountables = [], [], []
+          else
+            instance_variable_set "@#{scope}", []
+        end
+      end
     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])
+    extend self
+
+    # Yields a singleton instance of Inflector::Inflections so you can specify additional
+    # inflector rules.
+    #
+    # Example:
+    #   Inflector.inflections do |inflect|
+    #     inflect.uncountable "rails"
+    #   end
+    def inflections
+      if block_given?
+        yield Inflections.instance
+      else
+        Inflections.instance
+      end
     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.
+    # Returns the plural form of the word in the string.
     #
     # Examples:
-    #   irregular 'octopus', 'octopi'
-    #   irregular 'person', 'people'
-    def irregular(singular, plural)
-      if singular[0,1].upcase == plural[0,1].upcase
-        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])
+    #   "post".pluralize             # => "posts"
+    #   "octopus".pluralize          # => "octopi"
+    #   "sheep".pluralize            # => "sheep"
+    #   "words".pluralize            # => "words"
+    #   "the blue mailman".pluralize # => "the blue mailmen"
+    #   "CamelOctopus".pluralize     # => "CamelOctopi"
+    def pluralize(word)
+      result = word.to_s.dup
+
+      if word.empty? || inflections.uncountables.include?(result.downcase)
+        result
       else
-        plural(Regexp.new("#{singular[0,1].upcase}(?i)#{singular[1..-1]}$"), plural[0,1].upcase + plural[1..-1])
-        plural(Regexp.new("#{singular[0,1].downcase}(?i)#{singular[1..-1]}$"), plural[0,1].downcase + plural[1..-1])
-        singular(Regexp.new("#{plural[0,1].upcase}(?i)#{plural[1..-1]}$"), singular[0,1].upcase + singular[1..-1])
-        singular(Regexp.new("#{plural[0,1].downcase}(?i)#{plural[1..-1]}$"), singular[0,1].downcase + singular[1..-1])       
+        inflections.plurals.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
+        result
       end
     end
 
-    # Add uncountable words that shouldn't be attempted inflected.
+    # The reverse of +pluralize+, returns the singular form of a word in a string.
     #
     # Examples:
-    #   uncountable "money"
-    #   uncountable "money", "information"
-    #   uncountable %w( money information rice )
-    def uncountable(*words)
-      (@uncountables << words).flatten!
+    #   "posts".singularize            # => "post"
+    #   "octopi".singularize           # => "octopus"
+    #   "sheep".singluarize            # => "sheep"
+    #   "word".singluarize             # => "word"
+    #   "the blue mailmen".singularize # => "the blue mailman"
+    #   "CamelOctopi".singularize      # => "CamelOctopus"
+    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
 
-    # Clears the loaded inflections within a given scope (default is <tt>:all</tt>).
-    # Give the scope as a symbol of the inflection type, the options are: <tt>:plurals</tt>,
-    # <tt>:singulars</tt>, <tt>:uncountables</tt>.
+    # By default, +camelize+ converts strings to UpperCamelCase. If the argument to +camelize+
+    # is set to <tt>:lower</tt> then +camelize+ produces lowerCamelCase.
     #
+    # +camelize+ will also convert '/' to '::' which is useful for converting paths to namespaces.
+    #
     # Examples:
-    #   clear :all
-    #   clear :plurals
-    def clear(scope = :all)
-      case scope
-        when :all
-          @plurals, @singulars, @uncountables = [], [], []
-        else
-          instance_variable_set "@#{scope}", []
+    #   "active_record".camelize                # => "ActiveRecord"
+    #   "active_record".camelize(:lower)        # => "activeRecord"
+    #   "active_record/errors".camelize         # => "ActiveRecord::Errors"
+    #   "active_record/errors".camelize(:lower) # => "activeRecord::Errors"
+    def camelize(lower_case_and_underscored_word, first_letter_in_uppercase = true)
+      if first_letter_in_uppercase
+        lower_case_and_underscored_word.to_s.gsub(/\/(.?)/) { "::#{$1.upcase}" }.gsub(/(?:^|_)(.)/) { $1.upcase }
+      else
+        lower_case_and_underscored_word.first + camelize(lower_case_and_underscored_word)[1..-1]
       end
     end
-  end
 
-  extend self
+    # Capitalizes all the words and replaces some characters in the string to create
+    # a nicer looking title. +titleize+ is meant for creating pretty output. It is not
+    # used in the Rails internals.
+    #
+    # +titleize+ is also aliased as as +titlecase+.
+    #
+    # Examples:
+    #   "man from the boondocks".titleize # => "Man From The Boondocks"
+    #   "x-men: the last stand".titleize  # => "X Men: The Last Stand"
+    def titleize(word)
+      humanize(underscore(word)).gsub(/\b('?[a-z])/) { $1.capitalize }
+    end
 
-  # Yields a singleton instance of Inflector::Inflections so you can specify additional
-  # inflector rules.
-  #
-  # Example:
-  #   Inflector.inflections do |inflect|
-  #     inflect.uncountable "rails"
-  #   end
-  def inflections
-    if block_given?
-      yield Inflections.instance
-    else
-      Inflections.instance
+    # The reverse of +camelize+. Makes an underscored, lowercase form from the expression in the string.
+    #
+    # Changes '::' to '/' to convert namespaces to paths.
+    #
+    # Examples:
+    #   "ActiveRecord".underscore         # => "active_record"
+    #   "ActiveRecord::Errors".underscore # => active_record/errors
+    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').
+        tr("-", "_").
+        downcase
     end
-  end
 
-  # Returns the plural form of the word in the string.
-  #
-  # Examples:
-  #   "post".pluralize             # => "posts"
-  #   "octopus".pluralize          # => "octopi"
-  #   "sheep".pluralize            # => "sheep"
-  #   "words".pluralize            # => "words"
-  #   "the blue mailman".pluralize # => "the blue mailmen"
-  #   "CamelOctopus".pluralize     # => "CamelOctopi"
-  def pluralize(word)
-    result = word.to_s.dup
+    # Replaces underscores with dashes in the string.
+    #
+    # Example:
+    #   "puni_puni" # => "puni-puni"
+    def dasherize(underscored_word)
+      underscored_word.gsub(/_/, '-')
+    end
 
-    if word.empty? || inflections.uncountables.include?(result.downcase)
-      result
-    else
-      inflections.plurals.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
-      result
+    # Capitalizes the first word and turns underscores into spaces and strips a
+    # trailing "_id", if any. Like +titleize+, this is meant for creating pretty output.
+    #
+    # Examples:
+    #   "employee_salary" # => "Employee salary"
+    #   "author_id"       # => "Author"
+    def humanize(lower_case_and_underscored_word)
+      lower_case_and_underscored_word.to_s.gsub(/_id$/, "").gsub(/_/, " ").capitalize
     end
-  end
 
-  # The reverse of +pluralize+, returns the singular form of a word in a string.
-  #
-  # Examples:
-  #   "posts".singularize            # => "post"
-  #   "octopi".singularize           # => "octopus"
-  #   "sheep".singluarize            # => "sheep"
-  #   "word".singluarize             # => "word"
-  #   "the blue mailmen".singularize # => "the blue mailman"
-  #   "CamelOctopi".singularize      # => "CamelOctopus"
-  def singularize(word)
-    result = word.to_s.dup
+    # Removes the module part from the expression in the string.
+    #
+    # Examples:
+    #   "ActiveRecord::CoreExtensions::String::Inflections".demodulize # => "Inflections"
+    #   "Inflections".demodulize                                       # => "Inflections"
+    def demodulize(class_name_in_module)
+      class_name_in_module.to_s.gsub(/^.*::/, '')
+    end
 
-    if inflections.uncountables.include?(result.downcase)
-      result
-    else
-      inflections.singulars.each { |(rule, replacement)| break if result.gsub!(rule, replacement) }
-      result
+    # Create the name of a table like Rails does for models to table names. This method
+    # uses the +pluralize+ method on the last word in the string.
+    #
+    # Examples
+    #   "RawScaledScorer".tableize # => "raw_scaled_scorers"
+    #   "egg_and_ham".tableize     # => "egg_and_hams"
+    #   "fancyCategory".tableize   # => "fancy_categories"
+    def tableize(class_name)
+      pluralize(underscore(class_name))
     end
-  end
 
-  # By default, +camelize+ converts strings to UpperCamelCase. If the argument to +camelize+
-  # is set to <tt>:lower</tt> then +camelize+ produces lowerCamelCase.
-  #
-  # +camelize+ will also convert '/' to '::' which is useful for converting paths to namespaces.
-  #
-  # Examples:
-  #   "active_record".camelize                # => "ActiveRecord"
-  #   "active_record".camelize(:lower)        # => "activeRecord"
-  #   "active_record/errors".camelize         # => "ActiveRecord::Errors"
-  #   "active_record/errors".camelize(:lower) # => "activeRecord::Errors"
-  def camelize(lower_case_and_underscored_word, first_letter_in_uppercase = true)
-    if first_letter_in_uppercase
-      lower_case_and_underscored_word.to_s.gsub(/\/(.?)/) { "::#{$1.upcase}" }.gsub(/(?:^|_)(.)/) { $1.upcase }
-    else
-      lower_case_and_underscored_word.first + camelize(lower_case_and_underscored_word)[1..-1]
+    # Create a class name from a plural table name like Rails does for table names to models.
+    # Note that this returns a string and not a Class. (To convert to an actual class
+    # follow +classify+ with +constantize+.)
+    #
+    # Examples:
+    #   "egg_and_hams".classify # => "EggAndHam"
+    #   "posts".classify        # => "Post"
+    #
+    # Singular names are not handled correctly:
+    #   "business".classify     # => "Busines"
+    def classify(table_name)
+      # strip out any leading schema name
+      camelize(singularize(table_name.to_s.sub(/.*\./, '')))
     end
-  end
 
-  # Capitalizes all the words and replaces some characters in the string to create
-  # a nicer looking title. +titleize+ is meant for creating pretty output. It is not
-  # used in the Rails internals.
-  #
-  # +titleize+ is also aliased as as +titlecase+.
-  #
-  # Examples:
-  #   "man from the boondocks".titleize # => "Man From The Boondocks"
-  #   "x-men: the last stand".titleize  # => "X Men: The Last Stand"
-  def titleize(word)
-    humanize(underscore(word)).gsub(/\b('?[a-z])/) { $1.capitalize }
-  end
+    # Creates a foreign key name from a class name.
+    # +separate_class_name_and_id_with_underscore+ sets whether
+    # the method should put '_' between the name and 'id'.
+    #
+    # Examples:
+    #   "Message".foreign_key        # => "message_id"
+    #   "Message".foreign_key(false) # => "messageid"
+    #   "Admin::Post".foreign_key    # => "post_id"
+    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
 
-  # The reverse of +camelize+. Makes an underscored, lowercase form from the expression in the string.
-  #
-  # Changes '::' to '/' to convert namespaces to paths.
-  #
-  # Examples:
-  #   "ActiveRecord".underscore         # => "active_record"
-  #   "ActiveRecord::Errors".underscore # => active_record/errors
-  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').
-      tr("-", "_").
-      downcase
-  end
+    # Tries to find a constant with the name specified in the argument string:
+    #
+    #   "Module".constantize     # => Module
+    #   "Test::Unit".constantize # => Test::Unit
+    #
+    # The name is assumed to be the one of a top-level constant, no matter whether
+    # it starts with "::" or not. No lexical context is taken into account:
+    #
+    #   C = 'outside'
+    #   module M
+    #     C = 'inside'
+    #     C               # => 'inside'
+    #     "C".constantize # => 'outside', same as ::C
+    #   end
+    #
+    # NameError is raised when the name is not in CamelCase or the constant is
+    # unknown.
+    def constantize(camel_cased_word)
+      names = camel_cased_word.split('::')
+      names.shift if names.empty? || names.first.empty?
 
-  # Replaces underscores with dashes in the string.
-  #
-  # Example:
-  #   "puni_puni" # => "puni-puni"
-  def dasherize(underscored_word)
-    underscored_word.gsub(/_/, '-')
-  end
-
-  # Capitalizes the first word and turns underscores into spaces and strips a
-  # trailing "_id", if any. Like +titleize+, this is meant for creating pretty output.
-  #
-  # Examples:
-  #   "employee_salary" # => "Employee salary"
-  #   "author_id"       # => "Author"
-  def humanize(lower_case_and_underscored_word)
-    lower_case_and_underscored_word.to_s.gsub(/_id$/, "").gsub(/_/, " ").capitalize
-  end
-
-  # Removes the module part from the expression in the string.
-  #
-  # Examples:
-  #   "ActiveRecord::CoreExtensions::String::Inflections".demodulize # => "Inflections"
-  #   "Inflections".demodulize                                       # => "Inflections"
-  def demodulize(class_name_in_module)
-    class_name_in_module.to_s.gsub(/^.*::/, '')
-  end
-
-  # Create the name of a table like Rails does for models to table names. This method
-  # uses the +pluralize+ method on the last word in the string.
-  #
-  # Examples
-  #   "RawScaledScorer".tableize # => "raw_scaled_scorers"
-  #   "egg_and_ham".tableize     # => "egg_and_hams"
-  #   "fancyCategory".tableize   # => "fancy_categories"
-  def tableize(class_name)
-    pluralize(underscore(class_name))
-  end
-
-  # Create a class name from a plural table name like Rails does for table names to models.
-  # Note that this returns a string and not a Class. (To convert to an actual class
-  # follow +classify+ with +constantize+.)
-  #
-  # Examples:
-  #   "egg_and_hams".classify # => "EggAndHam"
-  #   "posts".classify        # => "Post"
-  #
-  # Singular names are not handled correctly:
-  #   "business".classify     # => "Busines"
-  def classify(table_name)
-    # strip out any leading schema name
-    camelize(singularize(table_name.to_s.sub(/.*\./, '')))
-  end
-
-  # Creates a foreign key name from a class name.
-  # +separate_class_name_and_id_with_underscore+ sets whether
-  # the method should put '_' between the name and 'id'.
-  #
-  # Examples:
-  #   "Message".foreign_key        # => "message_id"
-  #   "Message".foreign_key(false) # => "messageid"
-  #   "Admin::Post".foreign_key    # => "post_id"
-  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
-
-  # Tries to find a constant with the name specified in the argument string:
-  #
-  #   "Module".constantize     # => Module
-  #   "Test::Unit".constantize # => Test::Unit
-  #
-  # The name is assumed to be the one of a top-level constant, no matter whether
-  # it starts with "::" or not. No lexical context is taken into account:
-  #
-  #   C = 'outside'
-  #   module M
-  #     C = 'inside'
-  #     C               # => 'inside'
-  #     "C".constantize # => 'outside', same as ::C
-  #   end
-  #
-  # NameError is raised when the name is not in CamelCase or the constant is
-  # unknown.
-  def constantize(camel_cased_word)
-    unless /\A(?:::)?([A-Z]\w*(?:::[A-Z]\w*)*)\z/ =~ camel_cased_word
-      raise NameError, "#{camel_cased_word.inspect} is not a valid constant name!"
+      constant = Object
+      names.each do |name|
+        constant = constant.const_defined?(name) ? constant.const_get(name) : constant.const_missing(name)
+      end
+      constant
     end
 
-    Object.module_eval("::#{$1}", __FILE__, __LINE__)
-  end
-
-  # Turns a number into an ordinal string used to denote the position in an
-  # ordered sequence such as 1st, 2nd, 3rd, 4th.
-  #
-  # Examples:
-  #   ordinalize(1)     # => "1st"
-  #   ordinalize(2)     # => "2nd"
-  #   ordinalize(1002)  # => "1002nd"
-  #   ordinalize(1003)  # => "1003rd"
-  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"
+    # Turns a number into an ordinal string used to denote the position in an
+    # ordered sequence such as 1st, 2nd, 3rd, 4th.
+    #
+    # Examples:
+    #   ordinalize(1)     # => "1st"
+    #   ordinalize(2)     # => "2nd"
+    #   ordinalize(1002)  # => "1002nd"
+    #   ordinalize(1003)  # => "1003rd"
+    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
 end
 