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-rw-r--r--actionview/lib/action_view/base.rb8
-rw-r--r--actionview/lib/action_view/dependency_tracker.rb19
-rw-r--r--actionview/lib/action_view/helpers/asset_tag_helper.rb1
-rw-r--r--actionview/lib/action_view/helpers/cache_helper.rb35
-rw-r--r--actionview/lib/action_view/helpers/form_helper.rb9
-rw-r--r--actionview/lib/action_view/helpers/form_tag_helper.rb3
-rw-r--r--actionview/lib/action_view/helpers/record_tag_helper.rb111
-rw-r--r--actionview/lib/action_view/helpers/translation_helper.rb6
-rw-r--r--actionview/lib/action_view/helpers/url_helper.rb2
-rw-r--r--actionview/lib/action_view/railtie.rb6
-rw-r--r--actionview/lib/action_view/renderer/partial_renderer.rb8
-rw-r--r--actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb70
-rw-r--r--actionview/lib/action_view/tasks/dependencies.rake16
-rw-r--r--actionview/lib/action_view/template.rb29
-rw-r--r--actionview/lib/action_view/template/handlers/erb.rb18
15 files changed, 219 insertions, 122 deletions
diff --git a/actionview/lib/action_view/base.rb b/actionview/lib/action_view/base.rb
index 1feafc1094..43124bb904 100644
--- a/actionview/lib/action_view/base.rb
+++ b/actionview/lib/action_view/base.rb
@@ -70,6 +70,14 @@ module ActionView #:nodoc:
# Headline: <%= headline %>
# First name: <%= person.first_name %>
#
+ # The local variables passed to sub templates can be accessed as a hash using the <tt>local_assigns</tt> hash. This lets you access the
+ # variables as:
+ #
+ # Headline: <%= local_assigns[:headline] %>
+ #
+ # This is useful in cases where you aren't sure if the local variable has been assigned. Alternately, you could also use
+ # <tt>defined? headline</tt> to first check if the variable has been assigned before using it.
+ #
# === Template caching
#
# By default, Rails will compile each template to a method in order to render it. When you alter a template,
diff --git a/actionview/lib/action_view/dependency_tracker.rb b/actionview/lib/action_view/dependency_tracker.rb
index e34bdd4a46..7a7e116dbb 100644
--- a/actionview/lib/action_view/dependency_tracker.rb
+++ b/actionview/lib/action_view/dependency_tracker.rb
@@ -76,6 +76,12 @@ module ActionView
(?:#{STRING}|#{VARIABLE_OR_METHOD_CHAIN}) # finally, the dependency name of interest
/xm
+ LAYOUT_DEPENDENCY = /\A
+ (?:\s*\(?\s*) # optional opening paren surrounded by spaces
+ (?:.*?#{LAYOUT_HASH_KEY}) # check if the line has layout key declaration
+ (?:#{STRING}|#{VARIABLE_OR_METHOD_CHAIN}) # finally, the dependency name of interest
+ /xm
+
def self.call(name, template)
new(name, template).dependencies
end
@@ -106,15 +112,20 @@ module ActionView
render_calls = source.split(/\brender\b/).drop(1)
render_calls.each do |arguments|
- arguments.scan(RENDER_ARGUMENTS) do
- add_dynamic_dependency(render_dependencies, Regexp.last_match[:dynamic])
- add_static_dependency(render_dependencies, Regexp.last_match[:static])
- end
+ add_dependencies(render_dependencies, arguments, LAYOUT_DEPENDENCY)
+ add_dependencies(render_dependencies, arguments, RENDER_ARGUMENTS)
end
render_dependencies.uniq
end
+ def add_dependencies(render_dependencies, arguments, pattern)
+ arguments.scan(pattern) do
+ add_dynamic_dependency(render_dependencies, Regexp.last_match[:dynamic])
+ add_static_dependency(render_dependencies, Regexp.last_match[:static])
+ end
+ end
+
def add_dynamic_dependency(dependencies, dependency)
if dependency
dependencies << "#{dependency.pluralize}/#{dependency.singularize}"
diff --git a/actionview/lib/action_view/helpers/asset_tag_helper.rb b/actionview/lib/action_view/helpers/asset_tag_helper.rb
index b7fdc16a9d..5c28043f8a 100644
--- a/actionview/lib/action_view/helpers/asset_tag_helper.rb
+++ b/actionview/lib/action_view/helpers/asset_tag_helper.rb
@@ -318,6 +318,7 @@ module ActionView
end
def extract_dimensions(size)
+ size = size.to_s
if size =~ %r{\A\d+x\d+\z}
size.split('x')
elsif size =~ %r{\A\d+\z}
diff --git a/actionview/lib/action_view/helpers/cache_helper.rb b/actionview/lib/action_view/helpers/cache_helper.rb
index 4db8930a26..0e2a5f90f4 100644
--- a/actionview/lib/action_view/helpers/cache_helper.rb
+++ b/actionview/lib/action_view/helpers/cache_helper.rb
@@ -110,6 +110,29 @@ module ActionView
# <%= some_helper_method(person) %>
#
# Now all you'll have to do is change that timestamp when the helper method changes.
+ #
+ # === Automatic Collection Caching
+ #
+ # When rendering collections such as:
+ #
+ # <%= render @notifications %>
+ # <%= render partial: 'notifications/notification', collection: @notifications %>
+ #
+ # If the notifications/_notification partial starts with a cache call like so:
+ #
+ # <% cache notification do %>
+ # <%= notification.name %>
+ # <% end %>
+ #
+ # The collection can then automatically use any cached renders for that
+ # template by reading them at once instead of one by one.
+ #
+ # See ActionView::Template::Handlers::ERB.resource_cache_call_pattern for more
+ # information on what cache calls make a template eligible for this collection caching.
+ #
+ # The automatic cache multi read can be turned off like so:
+ #
+ # <%= render @notifications, cache: false %>
def cache(name = {}, options = nil, &block)
if controller.perform_caching
safe_concat(fragment_for(cache_fragment_name(name, options), options, &block))
@@ -122,7 +145,7 @@ module ActionView
# Cache fragments of a view if +condition+ is true
#
- # <%= cache_if admin?, project do %>
+ # <% cache_if admin?, project do %>
# <b>All the topics on this project</b>
# <%= render project.topics %>
# <% end %>
@@ -138,7 +161,7 @@ module ActionView
# Cache fragments of a view unless +condition+ is true
#
- # <%= cache_unless admin?, project do %>
+ # <% cache_unless admin?, project do %>
# <b>All the topics on this project</b>
# <%= render project.topics %>
# <% end %>
@@ -161,6 +184,14 @@ module ActionView
end
end
+ # Given a key (as described in ActionController::Caching::Fragments.expire_fragment),
+ # returns a key suitable for use in reading, writing, or expiring a
+ # cached fragment. All keys are prefixed with <tt>views/</tt> and uses
+ # ActiveSupport::Cache.expand_cache_key for the expansion.
+ def fragment_cache_key(key)
+ ActiveSupport::Cache.expand_cache_key(key.is_a?(Hash) ? url_for(key).split("://").last : key, :views)
+ end
+
private
def fragment_name_with_digest(name) #:nodoc:
diff --git a/actionview/lib/action_view/helpers/form_helper.rb b/actionview/lib/action_view/helpers/form_helper.rb
index 8d78ba13d5..b0793d0b91 100644
--- a/actionview/lib/action_view/helpers/form_helper.rb
+++ b/actionview/lib/action_view/helpers/form_helper.rb
@@ -4,6 +4,7 @@ require 'action_view/helpers/tag_helper'
require 'action_view/helpers/form_tag_helper'
require 'action_view/helpers/active_model_helper'
require 'action_view/model_naming'
+require 'action_view/record_identifier'
require 'active_support/core_ext/module/attribute_accessors'
require 'active_support/core_ext/hash/slice'
require 'active_support/core_ext/string/output_safety'
@@ -110,6 +111,7 @@ module ActionView
include FormTagHelper
include UrlHelper
include ModelNaming
+ include RecordIdentifier
# Creates a form that allows the user to create or update the attributes
# of a specific model object.
@@ -1224,11 +1226,11 @@ module ActionView
object_name = model_name_from_record_or_class(object).param_key
end
- builder = options[:builder] || default_form_builder
+ builder = options[:builder] || default_form_builder_class
builder.new(object_name, object, self, options)
end
- def default_form_builder
+ def default_form_builder_class
builder = ActionView::Base.default_form_builder
builder.respond_to?(:constantize) ? builder.constantize : builder
end
@@ -1244,7 +1246,7 @@ module ActionView
# Admin: <%= person_form.check_box :admin %>
# <% end %>
#
- # In the above block, the a +FormBuilder+ object is yielded as the
+ # In the above block, a +FormBuilder+ object is yielded as the
# +person_form+ variable. This allows you to generate the +text_field+
# and +check_box+ fields by specifying their eponymous methods, which
# modify the underlying template and associates the +@person+ model object
@@ -1265,6 +1267,7 @@ module ActionView
# )
# )
# end
+ # end
#
# The above code creates a new method +div_radio_button+ which wraps a div
# around the new radio button. Note that when options are passed in, you
diff --git a/actionview/lib/action_view/helpers/form_tag_helper.rb b/actionview/lib/action_view/helpers/form_tag_helper.rb
index 8bb243b8b7..65a0548ffb 100644
--- a/actionview/lib/action_view/helpers/form_tag_helper.rb
+++ b/actionview/lib/action_view/helpers/form_tag_helper.rb
@@ -84,14 +84,13 @@ module ActionView
# * <tt>:disabled</tt> - If set to true, the user will not be able to use this input.
# * <tt>:include_blank</tt> - If set to true, an empty option will be created. If set to a string, the string will be used as the option's content and the value will be empty.
# * <tt>:prompt</tt> - Create a prompt option with blank value and the text asking user to select something.
- # * <tt>:selected</tt> - Provide a default selected value. It should be of the exact type as the provided options.
# * Any other key creates standard HTML attributes for the tag.
#
# ==== Examples
# select_tag "people", options_from_collection_for_select(@people, "id", "name")
# # <select id="people" name="people"><option value="1">David</option></select>
#
- # select_tag "people", options_from_collection_for_select(@people, "id", "name"), selected: ["1", "David"]
+ # select_tag "people", options_from_collection_for_select(@people, "id", "name", "1")
# # <select id="people" name="people"><option value="1" selected="selected">David</option></select>
#
# select_tag "people", "<option>David</option>".html_safe
diff --git a/actionview/lib/action_view/helpers/record_tag_helper.rb b/actionview/lib/action_view/helpers/record_tag_helper.rb
index 77c3e6d394..f7ee573035 100644
--- a/actionview/lib/action_view/helpers/record_tag_helper.rb
+++ b/actionview/lib/action_view/helpers/record_tag_helper.rb
@@ -1,108 +1,21 @@
-require 'action_view/record_identifier'
-
module ActionView
- # = Action View Record Tag Helpers
module Helpers
module RecordTagHelper
- include ActionView::RecordIdentifier
-
- # Produces a wrapper DIV element with id and class parameters that
- # relate to the specified Active Record object. Usage example:
- #
- # <%= div_for(@person, class: "foo") do %>
- # <%= @person.name %>
- # <% end %>
- #
- # produces:
- #
- # <div id="person_123" class="person foo"> Joe Bloggs </div>
- #
- # You can also pass an array of Active Record objects, which will then
- # get iterated over and yield each record as an argument for the block.
- # For example:
- #
- # <%= div_for(@people, class: "foo") do |person| %>
- # <%= person.name %>
- # <% end %>
- #
- # produces:
- #
- # <div id="person_123" class="person foo"> Joe Bloggs </div>
- # <div id="person_124" class="person foo"> Jane Bloggs </div>
- #
- def div_for(record, *args, &block)
- content_tag_for(:div, record, *args, &block)
+ def div_for(*)
+ raise NoMethodError, "The `div_for` method has been removed from " \
+ "Rails. To continue using it, add the `record_tag_helper` gem to " \
+ "your Gemfile:\n" \
+ " gem 'record_tag_helper', '~> 1.0'\n" \
+ "Consult the Rails upgrade guide for details."
end
- # content_tag_for creates an HTML element with id and class parameters
- # that relate to the specified Active Record object. For example:
- #
- # <%= content_tag_for(:tr, @person) do %>
- # <td><%= @person.first_name %></td>
- # <td><%= @person.last_name %></td>
- # <% end %>
- #
- # would produce the following HTML (assuming @person is an instance of
- # a Person object, with an id value of 123):
- #
- # <tr id="person_123" class="person">....</tr>
- #
- # If you require the HTML id attribute to have a prefix, you can specify it:
- #
- # <%= content_tag_for(:tr, @person, :foo) do %> ...
- #
- # produces:
- #
- # <tr id="foo_person_123" class="person">...
- #
- # You can also pass an array of objects which this method will loop through
- # and yield the current object to the supplied block, reducing the need for
- # having to iterate through the object (using <tt>each</tt>) beforehand.
- # For example (assuming @people is an array of Person objects):
- #
- # <%= content_tag_for(:tr, @people) do |person| %>
- # <td><%= person.first_name %></td>
- # <td><%= person.last_name %></td>
- # <% end %>
- #
- # produces:
- #
- # <tr id="person_123" class="person">...</tr>
- # <tr id="person_124" class="person">...</tr>
- #
- # content_tag_for also accepts a hash of options, which will be converted to
- # additional HTML attributes. If you specify a <tt>:class</tt> value, it will be combined
- # with the default class name for your object. For example:
- #
- # <%= content_tag_for(:li, @person, class: "bar") %>...
- #
- # produces:
- #
- # <li id="person_123" class="person bar">...
- #
- def content_tag_for(tag_name, single_or_multiple_records, prefix = nil, options = nil, &block)
- options, prefix = prefix, nil if prefix.is_a?(Hash)
-
- Array(single_or_multiple_records).map do |single_record|
- content_tag_for_single_record(tag_name, single_record, prefix, options, &block)
- end.join("\n").html_safe
+ def content_tag_for(*)
+ raise NoMethodError, "The `content_tag_for` method has been removed from " \
+ "Rails. To continue using it, add the `record_tag_helper` gem to " \
+ "your Gemfile:\n" \
+ " gem 'record_tag_helper', '~> 1.0'\n" \
+ "Consult the Rails upgrade guide for details."
end
-
- private
-
- # Called by <tt>content_tag_for</tt> internally to render a content tag
- # for each record.
- def content_tag_for_single_record(tag_name, record, prefix, options, &block)
- options = options ? options.dup : {}
- options[:class] = [ dom_class(record, prefix), options[:class] ].compact
- options[:id] = dom_id(record, prefix)
-
- if block_given?
- content_tag(tag_name, capture(record, &block), options)
- else
- content_tag(tag_name, "", options)
- end
- end
end
end
end
diff --git a/actionview/lib/action_view/helpers/translation_helper.rb b/actionview/lib/action_view/helpers/translation_helper.rb
index 342361217c..24b633c5bb 100644
--- a/actionview/lib/action_view/helpers/translation_helper.rb
+++ b/actionview/lib/action_view/helpers/translation_helper.rb
@@ -37,8 +37,12 @@ module ActionView
# you know what kind of output to expect when you call translate in a template.
def translate(key, options = {})
options = options.dup
+ has_default = options.has_key?(:default)
remaining_defaults = Array(options.delete(:default))
- options[:default] = remaining_defaults.shift if remaining_defaults.first.kind_of? String
+
+ if has_default && !remaining_defaults.first.kind_of?(Symbol)
+ options[:default] = remaining_defaults.shift
+ end
# If the user has explicitly decided to NOT raise errors, pass that option to I18n.
# Otherwise, tell I18n to raise an exception, which we rescue further in this method.
diff --git a/actionview/lib/action_view/helpers/url_helper.rb b/actionview/lib/action_view/helpers/url_helper.rb
index 33882063f9..3dbce0738e 100644
--- a/actionview/lib/action_view/helpers/url_helper.rb
+++ b/actionview/lib/action_view/helpers/url_helper.rb
@@ -459,7 +459,7 @@ module ActionView
html_options = (html_options || {}).stringify_keys
extras = %w{ cc bcc body subject reply_to }.map! { |item|
- option = html_options.delete(item) || next
+ option = html_options.delete(item).presence || next
"#{item.dasherize}=#{Rack::Utils.escape_path(option)}"
}.compact
extras = extras.empty? ? '' : '?' + extras.join('&')
diff --git a/actionview/lib/action_view/railtie.rb b/actionview/lib/action_view/railtie.rb
index ee3dce24b7..9a26cba574 100644
--- a/actionview/lib/action_view/railtie.rb
+++ b/actionview/lib/action_view/railtie.rb
@@ -36,6 +36,12 @@ module ActionView
end
end
+ initializer "action_view.collection_caching" do |app|
+ ActiveSupport.on_load(:action_controller) do
+ PartialRenderer.collection_cache = app.config.action_controller.cache_store
+ end
+ end
+
initializer "action_view.setup_action_pack" do |app|
ActiveSupport.on_load(:action_controller) do
ActionView::RoutingUrlFor.include(ActionDispatch::Routing::UrlFor)
diff --git a/actionview/lib/action_view/renderer/partial_renderer.rb b/actionview/lib/action_view/renderer/partial_renderer.rb
index 5ff15411cf..56b8ab1e2d 100644
--- a/actionview/lib/action_view/renderer/partial_renderer.rb
+++ b/actionview/lib/action_view/renderer/partial_renderer.rb
@@ -1,3 +1,4 @@
+require 'action_view/renderer/partial_renderer/collection_caching'
require 'thread_safe'
module ActionView
@@ -280,6 +281,8 @@ module ActionView
# <%- end -%>
# <% end %>
class PartialRenderer < AbstractRenderer
+ include CollectionCaching
+
PREFIXED_PARTIAL_NAMES = ThreadSafe::Cache.new do |h, k|
h[k] = ThreadSafe::Cache.new
end
@@ -321,8 +324,9 @@ module ActionView
spacer = find_template(@options[:spacer_template], @locals.keys).render(@view, @locals)
end
- result = @template ? collection_with_template : collection_without_template
- result.join(spacer).html_safe
+ cache_collection_render do
+ @template ? collection_with_template : collection_without_template
+ end.join(spacer).html_safe
end
def render_partial
diff --git a/actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb b/actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb
new file mode 100644
index 0000000000..b77c884e66
--- /dev/null
+++ b/actionview/lib/action_view/renderer/partial_renderer/collection_caching.rb
@@ -0,0 +1,70 @@
+require 'active_support/core_ext/object/try'
+
+module ActionView
+ module CollectionCaching # :nodoc:
+ extend ActiveSupport::Concern
+
+ included do
+ # Fallback cache store if Action View is used without Rails.
+ # Otherwise overriden in Railtie to use Rails.cache.
+ mattr_accessor(:collection_cache) { ActiveSupport::Cache::MemoryStore.new }
+ end
+
+ private
+ def cache_collection_render
+ return yield unless cache_collection?
+
+ keyed_collection = collection_by_cache_keys
+ partial_cache = collection_cache.read_multi(*keyed_collection.keys)
+
+ @collection = keyed_collection.reject { |key, _| partial_cache.key?(key) }.values
+ rendered_partials = @collection.any? ? yield.dup : []
+
+ fetch_or_cache_partial(partial_cache, order_by: keyed_collection.each_key) do
+ rendered_partials.shift
+ end
+ end
+
+ def cache_collection?
+ @options.fetch(:cache, automatic_cache_eligible?)
+ end
+
+ def automatic_cache_eligible?
+ single_template_render? && !callable_cache_key? &&
+ @template.eligible_for_collection_caching?(as: @options[:as])
+ end
+
+ def single_template_render?
+ @template # Template is only set when a collection renders one template.
+ end
+
+ def callable_cache_key?
+ @options[:cache].respond_to?(:call)
+ end
+
+ def collection_by_cache_keys
+ seed = callable_cache_key? ? @options[:cache] : ->(i) { i }
+
+ @collection.each_with_object({}) do |item, hash|
+ hash[expanded_cache_key(seed.call(item))] = item
+ end
+ end
+
+ def expanded_cache_key(key)
+ key = @view.fragment_cache_key(@view.cache_fragment_name(key))
+ key.frozen? ? key.dup : key # #read_multi & #write may require mutability, Dalli 2.6.0.
+ end
+
+ def fetch_or_cache_partial(cached_partials, order_by:)
+ cache_options = @options[:cache_options] || @locals[:cache_options] || {}
+
+ order_by.map do |key|
+ cached_partials.fetch(key) do
+ yield.tap do |rendered_partial|
+ collection_cache.write(key, rendered_partial, cache_options)
+ end
+ end
+ end
+ end
+ end
+end
diff --git a/actionview/lib/action_view/tasks/dependencies.rake b/actionview/lib/action_view/tasks/dependencies.rake
index b39f7d583b..f394c319c1 100644
--- a/actionview/lib/action_view/tasks/dependencies.rake
+++ b/actionview/lib/action_view/tasks/dependencies.rake
@@ -2,20 +2,22 @@ namespace :cache_digests do
desc 'Lookup nested dependencies for TEMPLATE (like messages/show or comments/_comment.html)'
task :nested_dependencies => :environment do
abort 'You must provide TEMPLATE for the task to run' unless ENV['TEMPLATE'].present?
- puts JSON.pretty_generate ActionView::Digestor.new(name: template_name, finder: finder).nested_dependencies
+ puts JSON.pretty_generate ActionView::Digestor.new(name: CacheDigests.template_name, finder: CacheDigests.finder).nested_dependencies
end
desc 'Lookup first-level dependencies for TEMPLATE (like messages/show or comments/_comment.html)'
task :dependencies => :environment do
abort 'You must provide TEMPLATE for the task to run' unless ENV['TEMPLATE'].present?
- puts JSON.pretty_generate ActionView::Digestor.new(name: template_name, finder: finder).dependencies
+ puts JSON.pretty_generate ActionView::Digestor.new(name: CacheDigests.template_name, finder: CacheDigests.finder).dependencies
end
- def template_name
- ENV['TEMPLATE'].split('.', 2).first
- end
+ class CacheDigests
+ def self.template_name
+ ENV['TEMPLATE'].split('.', 2).first
+ end
- def finder
- ApplicationController.new.lookup_context
+ def self.finder
+ ApplicationController.new.lookup_context
+ end
end
end
diff --git a/actionview/lib/action_view/template.rb b/actionview/lib/action_view/template.rb
index 6b61378a1f..377ceb534a 100644
--- a/actionview/lib/action_view/template.rb
+++ b/actionview/lib/action_view/template.rb
@@ -87,6 +87,19 @@ module ActionView
# expected_encoding
# )
+ ##
+ # :method: local_assigns
+ #
+ # Returns a hash with the defined local variables.
+ #
+ # Given this sub template rendering:
+ #
+ # <%= render "shared/header", { headline: "Welcome", person: person } %>
+ #
+ # You can use +local_assigns+ in the sub templates to access the local variables:
+ #
+ # local_assigns[:headline] # => "Welcome"
+
eager_autoload do
autoload :Error
autoload :Handlers
@@ -103,7 +116,7 @@ module ActionView
# This finalizer is needed (and exactly with a proc inside another proc)
# otherwise templates leak in development.
- Finalizer = proc do |method_name, mod|
+ Finalizer = proc do |method_name, mod| # :nodoc:
proc do
mod.module_eval do
remove_possible_method method_name
@@ -117,6 +130,7 @@ module ActionView
@source = source
@identifier = identifier
@handler = handler
+ @cache_name = extract_resource_cache_call_name
@compiled = false
@original_encoding = nil
@locals = details[:locals] || []
@@ -152,6 +166,10 @@ module ActionView
@type ||= Types[@formats.first] if @formats.first
end
+ def eligible_for_collection_caching?(as: nil)
+ @cache_name == (as || inferred_cache_name).to_s
+ end
+
# Receives a view object and return a template similar to self by using @virtual_path.
#
# This method is useful if you have a template object but it does not contain its source
@@ -332,5 +350,14 @@ module ActionView
payload = { virtual_path: @virtual_path, identifier: @identifier }
ActiveSupport::Notifications.instrument("#{action}.action_view", payload, &block)
end
+
+ def extract_resource_cache_call_name
+ $1 if @handler.respond_to?(:resource_cache_call_pattern) &&
+ @source =~ @handler.resource_cache_call_pattern
+ end
+
+ def inferred_cache_name
+ @inferred_cache_name ||= @virtual_path.split('/').last.sub('_', '')
+ end
end
end
diff --git a/actionview/lib/action_view/template/handlers/erb.rb b/actionview/lib/action_view/template/handlers/erb.rb
index 85a100ed4c..88a8570706 100644
--- a/actionview/lib/action_view/template/handlers/erb.rb
+++ b/actionview/lib/action_view/template/handlers/erb.rb
@@ -123,6 +123,24 @@ module ActionView
).src
end
+ # Returns Regexp to extract a cached resource's name from a cache call at the
+ # first line of a template.
+ # The extracted cache name is expected in $1.
+ #
+ # <% cache notification do %> # => notification
+ #
+ # The pattern should support templates with a beginning comment:
+ #
+ # <%# Still extractable even though there's a comment %>
+ # <% cache notification do %> # => notification
+ #
+ # But fail to extract a name if a resource association is cached.
+ #
+ # <% cache notification.event do %> # => nil
+ def resource_cache_call_pattern
+ /\A(?:<%#.*%>\n?)?<% cache\(?\s*(\w+\.?)/
+ end
+
private
def valid_encoding(string, encoding)