require 'active_support/core_ext/object/try' require 'active_support/core_ext/object/blank' module ActionView # LookupContext is the object responsible to hold all information required to lookup # templates, i.e. view paths and details. The LookupContext is also responsible to # generate a key, given to view paths, used in the resolver cache lookup. Since # this key is generated just once during the request, it speeds up all cache accesses. class LookupContext #:nodoc: mattr_accessor :fallbacks @@fallbacks = [FileSystemResolver.new(""), FileSystemResolver.new("/")] mattr_accessor :registered_details self.registered_details = [] def self.register_detail(name, options = {}, &block) self.registered_details << name Setters.send :define_method, :"_#{name}_defaults", &block Setters.module_eval <<-METHOD, __FILE__, __LINE__ + 1 def #{name}=(value) value = Array(value.presence || _#{name}_defaults) #{"value << nil unless value.include?(nil)" unless options[:allow_nil] == false} unless value == @details[:#{name}] @details_key, @details = nil, @details.merge(:#{name} => value) @details.freeze end end METHOD end # Holds raw setters for the registered details. module Setters #:nodoc: end register_detail(:formats) { Mime::SET.symbols } register_detail(:locale) { [I18n.locale] } class DetailsKey #:nodoc: attr_reader :details alias :eql? :equal? @details_keys = Hash.new def self.get(details) @details_keys[details] ||= new(details) end def initialize(details) @details, @hash = details, details.hash end end def initialize(view_paths, details = {}) @details, @details_key = {}, nil self.view_paths = view_paths self.details = details end module ViewPaths attr_reader :view_paths # Whenever setting view paths, makes a copy so we can manipulate then in # instance objects as we wish. def view_paths=(paths) @view_paths = ActionView::Base.process_view_paths(paths) end def find(name, prefix = nil, partial = false) @view_paths.find(name, prefix, partial, details, details_key) end def find_all(name, prefix = nil, partial = false) @view_paths.find_all(name, prefix, partial, details, details_key) end def exists?(name, prefix = nil, partial = false) @view_paths.exists?(name, prefix, partial, details, details_key) end # Add fallbacks to the view paths. Useful in cases you are rendering a :file. def with_fallbacks added_resolvers = 0 self.class.fallbacks.each do |resolver| next if view_paths.include?(resolver) view_paths.push(resolver) added_resolvers += 1 end yield ensure added_resolvers.times { view_paths.pop } end end module Details attr_reader :details def details=(given_details) registered_details.each { |key| send(:"#{key}=", given_details[key]) } end def details_key @details_key ||= DetailsKey.get(@details) end # Shortcut to read formats from details. def formats @details[:formats].compact end # Overload formats= to reject [:"*/*"] values. def formats=(value, freeze=true) value = nil if value == [:"*/*"] super(value) end # Shortcut to read locale. def locale I18n.locale end # Overload locale= to also set the I18n.locale. If the current I18n.config object responds # to i18n_config, it means that it's has a copy of the original I18n configuration and it's # acting as proxy, which we need to skip. def locale=(value) value = value.first if value.is_a?(Array) config = I18n.config.respond_to?(:i18n_config) ? I18n.config.i18n_config : I18n.config config.locale = value if value super(I18n.locale) end # Update the details keys by merging the given hash into the current # details hash. If a block is given, the details are modified just during # the execution of the block and reverted to the previous value after. def update_details(new_details) old_details = @details self.details = old_details.merge(new_details) if block_given? begin yield ensure @details = old_details end end end end include Setters include Details include ViewPaths end end