Break up inflector to reduce the dependency burden on dependency-les methods like constantize.

1 files changed, 213 insertions, 0 deletions

diff --git a/activesupport/lib/active_support/inflector/inflections.rb b/activesupport/lib/active_support/inflector/inflections.rb
new file mode 100644
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+++ b/activesupport/lib/active_support/inflector/inflections.rb
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+# require "active_support/core_ext/string/access"
+
+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
+
+      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
+
+    # 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
+
+    # 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
+
+    # 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
+  end
+end
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