module ActiveSupport
module Inflector
# 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, :acronyms, :acronym_regex
def initialize
@plurals, @singulars, @uncountables, @humans, @acronyms, @acronym_regex = [], [], [], [], {}, /(?=a)b/
end
# Specifies a new acronym. An acronym must be specified as it will appear in a camelized string. An underscore
# string that contains the acronym will retain the acronym when passed to `camelize`, `humanize`, or `titleize`.
# A camelized string that contains the acronym will maintain the acronym when titleized or humanized, and will
# convert the acronym into a non-delimited single lowercase word when passed to +underscore+.
#
# Examples:
# acronym 'HTML'
# titleize 'html' #=> 'HTML'
# camelize 'html' #=> 'HTML'
# underscore 'MyHTML' #=> 'my_html'
#
# The acronym, however, must occur as a delimited unit and not be part of another word for conversions to recognize it:
#
# acronym 'HTTP'
# camelize 'my_http_delimited' #=> 'MyHTTPDelimited'
# camelize 'https' #=> 'Https', not 'HTTPs'
# underscore 'HTTPS' #=> 'http_s', not 'https'
#
# acronym 'HTTPS'
# camelize 'https' #=> 'HTTPS'
# underscore 'HTTPS' #=> 'https'
#
# Note: Acronyms that are passed to `pluralize` will no longer be recognized, since the acronym will not occur as
# a delimited unit in the pluralized result. To work around this, you must specify the pluralized form as an
# acronym as well:
#
# acronym 'API'
# camelize(pluralize('api')) #=> 'Apis'
#
# acronym 'APIs'
# camelize(pluralize('api')) #=> 'APIs'
#
# `acronym` may be used to specify any word that contains an acronym or otherwise needs to maintain a non-standard
# capitalization. The only restriction is that the word must begin with a capital letter.
#
# Examples:
# acronym 'RESTful'
# underscore 'RESTful' #=> 'restful'
# underscore 'RESTfulController' #=> 'restful_controller'
# titleize 'RESTfulController' #=> 'RESTful Controller'
# camelize 'restful' #=> 'RESTful'
# camelize 'restful_controller' #=> 'RESTfulController'
#
# acronym 'McDonald'
# underscore 'McDonald' #=> 'mcdonald'
# camelize 'mcdonald' #=> 'McDonald'
def acronym(word)
@acronyms[word.downcase] = word
@acronym_regex = /#{@acronyms.values.join("|")}/
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, @humans = [], [], [], []
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
end
end
