lib/active_support/inflector.rb in activesupport-3.0.0.beta4 vs lib/active_support/inflector.rb in activesupport-3.0.pre

- old
+ new

@@ -1,7 +1,410 @@ -# in case active_support/inflector is required without the rest of active_support -require 'active_support/inflector/inflections' -require 'active_support/inflector/transliterate' -require 'active_support/inflector/methods' +# encoding: utf-8 +require 'iconv' +require 'active_support/core_ext/object/blank' +require 'active_support/core_ext/string/access' +require 'active_support/core_ext/string/multibyte' +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. + # + # 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 + extend self + + # A singleton instance of this class is yielded by Inflector.inflections, which can then be used to specify additional + # inflection rules. Examples: + # + # ActiveSupport::Inflector.inflections do |inflect| + # inflect.plural /^(ox)$/i, '\1\2en' + # inflect.singular /^(ox)en/i, '\1' + # + # inflect.irregular 'octopus', 'octopi' + # + # inflect.uncountable "equipment" + # end + # + # New rules are added at the top. So in the example above, the irregular rule for octopus will now be the first of the + # pluralization and singularization rules that is runs. This guarantees that your rules run before any of the rules that may + # already have been loaded. + class Inflections + def self.instance + @__instance__ ||= new + end + + attr_reader :plurals, :singulars, :uncountables, :humans + + def initialize + @plurals, @singulars, @uncountables, @humans = [], [], [], [] + end + + # Specifies a new pluralization rule and its replacement. The rule can either be a string or a regular expression. + # The replacement should always be a string that may include references to the matched data from the rule. + def plural(rule, replacement) + @uncountables.delete(rule) if rule.is_a?(String) + @uncountables.delete(replacement) + @plurals.insert(0, [rule, replacement]) + end + + # Specifies a new singularization rule and its replacement. The rule can either be a string or a regular expression. + # The replacement should always be a string that may include references to the matched data from the rule. + def singular(rule, replacement) + @uncountables.delete(rule) if rule.is_a?(String) + @uncountables.delete(replacement) + @singulars.insert(0, [rule, replacement]) + end + + # Specifies a new irregular that applies to both pluralization and singularization at the same time. This can only be used + # for strings, not regular expressions. You simply pass the irregular in singular and plural form. + # + # Examples: + # irregular 'octopus', 'octopi' + # irregular 'person', 'people' + def irregular(singular, plural) + @uncountables.delete(singular) + @uncountables.delete(plural) + if singular[0,1].upcase == plural[0,1].upcase + plural(Regexp.new("(#{singular[0,1]})#{singular[1..-1]}$", "i"), '\1' + plural[1..-1]) + plural(Regexp.new("(#{plural[0,1]})#{plural[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]) + plural(Regexp.new("#{plural[0,1].upcase}(?i)#{plural[1..-1]}$"), plural[0,1].upcase + plural[1..-1]) + plural(Regexp.new("#{plural[0,1].downcase}(?i)#{plural[1..-1]}$"), 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 + + # Specifies a humanized form of a string by a regular expression rule or by a string mapping. + # When using a regular expression based replacement, the normal humanize formatting is called after the replacement. + # When a string is used, the human form should be specified as desired (example: 'The name', not 'the_name') + # + # Examples: + # human /_cnt$/i, '\1_count' + # human "legacy_col_person_name", "Name" + def human(rule, replacement) + @humans.insert(0, [rule, replacement]) + 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>, <tt>:humans</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 + + # Yields a singleton instance of Inflector::Inflections so you can specify additional + # inflector rules. + # + # Example: + # ActiveSupport::Inflector.inflections do |inflect| + # inflect.uncountable "rails" + # end + def inflections + if block_given? + yield Inflections.instance + else + Inflections.instance + 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" + # "CamelOctopus".pluralize # => "CamelOctopi" + def pluralize(word) + result = word.to_s.dup + + if word.empty? || inflections.uncountables.include?(result.downcase) + result + else + inflections.plurals.each { |(rule, replacement)| break if result.gsub!(rule, replacement) } + result + end + end + + # The reverse of +pluralize+, returns the singular form of a word in a string. + # + # Examples: + # "posts".singularize # => "post" + # "octopi".singularize # => "octopus" + # "sheep".singularize # => "sheep" + # "word".singularize # => "word" + # "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 + + # 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.to_s.first.downcase + camelize(lower_case_and_underscored_word)[1..-1] + 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])/) { $1.capitalize } + end + + # The reverse of +camelize+. Makes an underscored, lowercase form from the expression in the string. + # + # Changes '::' to '/' to convert namespaces to paths. + # + # Examples: + # "ActiveRecord".underscore # => "active_record" + # "ActiveRecord::Errors".underscore # => active_record/errors + def underscore(camel_cased_word) + camel_cased_word.to_s.gsub(/::/, '/'). + gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2'). + gsub(/([a-z\d])([A-Z])/,'\1_\2'). + tr("-", "_"). + downcase + end + + # Replaces underscores with dashes in the string. + # + # Example: + # "puni_puni" # => "puni-puni" + def dasherize(underscored_word) + underscored_word.gsub(/_/, '-') + end + + # Capitalizes the first word and turns underscores into spaces and strips a + # trailing "_id", if any. Like +titleize+, this is meant for creating pretty output. + # + # Examples: + # "employee_salary" # => "Employee salary" + # "author_id" # => "Author" + def humanize(lower_case_and_underscored_word) + result = lower_case_and_underscored_word.to_s.dup + + inflections.humans.each { |(rule, replacement)| break if result.gsub!(rule, replacement) } + result.gsub(/_id$/, "").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 + + # Replaces special characters in a string so that it may be used as part of a 'pretty' URL. + # + # ==== Examples + # + # class Person + # def to_param + # "#{id}-#{name.parameterize}" + # end + # end + # + # @person = Person.find(1) + # # => #<Person id: 1, name: "Donald E. Knuth"> + # + # <%= link_to(@person.name, person_path(@person)) %> + # # => <a href="/person/1-donald-e-knuth">Donald E. Knuth</a> + def parameterize(string, sep = '-') + # replace accented chars with their ascii equivalents + parameterized_string = transliterate(string) + # Turn unwanted chars into the separator + parameterized_string.gsub!(/[^a-z0-9\-_\+]+/i, sep) + unless sep.blank? + re_sep = Regexp.escape(sep) + # No more than one of the separator in a row. + parameterized_string.gsub!(/#{re_sep}{2,}/, sep) + # Remove leading/trailing separator. + parameterized_string.gsub!(/^#{re_sep}|#{re_sep}$/i, '') + end + parameterized_string.downcase + end + + + # Replaces accented characters with their ascii equivalents. + def transliterate(string) + Iconv.iconv('ascii//ignore//translit', 'utf-8', string).to_s + end + + if RUBY_VERSION >= '1.9' + undef_method :transliterate + def transliterate(string) + warn "Ruby 1.9 doesn't support Unicode normalization yet" + string.dup + end + + # The iconv transliteration code doesn't function correctly + # on some platforms, but it's very fast where it does function. + elsif "foo" != (Inflector.transliterate("föö") rescue nil) + undef_method :transliterate + def transliterate(string) + string.mb_chars.normalize(:kd). # Decompose accented characters + gsub(/[^\x00-\x7F]+/, '') # Remove anything non-ASCII entirely (e.g. diacritics). + end + 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 + + # Ruby 1.9 introduces an inherit argument for Module#const_get and + # #const_defined? and changes their default behavior. + if Module.method(:const_get).arity == 1 + # 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? + + constant = Object + names.each do |name| + constant = constant.const_defined?(name) ? constant.const_get(name) : constant.const_missing(name) + end + constant + end + else + def constantize(camel_cased_word) #:nodoc: + names = camel_cased_word.split('::') + names.shift if names.empty? || names.first.empty? + + constant = Object + names.each do |name| + constant = constant.const_get(name, false) || constant.const_missing(name) + end + constant + end + 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" + end + end + end + end +end + +# in case active_support/inflector is required without the rest of active_support require 'active_support/inflections' require 'active_support/core_ext/string/inflections'