diff options
Diffstat (limited to 'activesupport/lib/active_support/callbacks.rb')
| -rw-r--r-- | activesupport/lib/active_support/callbacks.rb | 255 |
1 files changed, 162 insertions, 93 deletions
diff --git a/activesupport/lib/active_support/callbacks.rb b/activesupport/lib/active_support/callbacks.rb index 24c702b602..f32bb8a0cc 100644 --- a/activesupport/lib/active_support/callbacks.rb +++ b/activesupport/lib/active_support/callbacks.rb @@ -4,6 +4,7 @@ require 'active_support/core_ext/array/extract_options' require 'active_support/core_ext/class/attribute' require 'active_support/core_ext/kernel/reporting' require 'active_support/core_ext/kernel/singleton_class' +require 'active_support/core_ext/string/filters' require 'thread' module ActiveSupport @@ -121,102 +122,106 @@ module ActiveSupport ENDING = End.new class Before - def self.build(next_callback, user_callback, user_conditions, chain_config, filter) + def self.build(callback_sequence, user_callback, user_conditions, chain_config, filter) halted_lambda = chain_config[:terminator] if chain_config.key?(:terminator) && user_conditions.any? - halting_and_conditional(next_callback, user_callback, user_conditions, halted_lambda, filter) + halting_and_conditional(callback_sequence, user_callback, user_conditions, halted_lambda, filter) elsif chain_config.key? :terminator - halting(next_callback, user_callback, halted_lambda, filter) + halting(callback_sequence, user_callback, halted_lambda, filter) elsif user_conditions.any? - conditional(next_callback, user_callback, user_conditions) + conditional(callback_sequence, user_callback, user_conditions) else - simple next_callback, user_callback + simple callback_sequence, user_callback end end - def self.halting_and_conditional(next_callback, user_callback, user_conditions, halted_lambda, filter) - lambda { |env| + def self.halting_and_conditional(callback_sequence, user_callback, user_conditions, halted_lambda, filter) + callback_sequence.before do |env| target = env.target value = env.value halted = env.halted if !halted && user_conditions.all? { |c| c.call(target, value) } - result = user_callback.call target, value - env.halted = halted_lambda.call(target, result) + result_lambda = -> { user_callback.call target, value } + env.halted = halted_lambda.call(target, result_lambda) if env.halted target.send :halted_callback_hook, filter end end - next_callback.call env - } + + env + end end private_class_method :halting_and_conditional - def self.halting(next_callback, user_callback, halted_lambda, filter) - lambda { |env| + def self.halting(callback_sequence, user_callback, halted_lambda, filter) + callback_sequence.before do |env| target = env.target value = env.value halted = env.halted unless halted - result = user_callback.call target, value - env.halted = halted_lambda.call(target, result) + result_lambda = -> { user_callback.call target, value } + env.halted = halted_lambda.call(target, result_lambda) + if env.halted target.send :halted_callback_hook, filter end end - next_callback.call env - } + + env + end end private_class_method :halting - def self.conditional(next_callback, user_callback, user_conditions) - lambda { |env| + def self.conditional(callback_sequence, user_callback, user_conditions) + callback_sequence.before do |env| target = env.target value = env.value if user_conditions.all? { |c| c.call(target, value) } user_callback.call target, value end - next_callback.call env - } + + env + end end private_class_method :conditional - def self.simple(next_callback, user_callback) - lambda { |env| + def self.simple(callback_sequence, user_callback) + callback_sequence.before do |env| user_callback.call env.target, env.value - next_callback.call env - } + + env + end end private_class_method :simple end class After - def self.build(next_callback, user_callback, user_conditions, chain_config) + def self.build(callback_sequence, user_callback, user_conditions, chain_config) if chain_config[:skip_after_callbacks_if_terminated] if chain_config.key?(:terminator) && user_conditions.any? - halting_and_conditional(next_callback, user_callback, user_conditions) + halting_and_conditional(callback_sequence, user_callback, user_conditions) elsif chain_config.key?(:terminator) - halting(next_callback, user_callback) + halting(callback_sequence, user_callback) elsif user_conditions.any? - conditional next_callback, user_callback, user_conditions + conditional callback_sequence, user_callback, user_conditions else - simple next_callback, user_callback + simple callback_sequence, user_callback end else if user_conditions.any? - conditional next_callback, user_callback, user_conditions + conditional callback_sequence, user_callback, user_conditions else - simple next_callback, user_callback + simple callback_sequence, user_callback end end end - def self.halting_and_conditional(next_callback, user_callback, user_conditions) - lambda { |env| - env = next_callback.call env + def self.halting_and_conditional(callback_sequence, user_callback, user_conditions) + callback_sequence.after do |env| target = env.target value = env.value halted = env.halted @@ -224,122 +229,119 @@ module ActiveSupport if !halted && user_conditions.all? { |c| c.call(target, value) } user_callback.call target, value end + env - } + end end private_class_method :halting_and_conditional - def self.halting(next_callback, user_callback) - lambda { |env| - env = next_callback.call env + def self.halting(callback_sequence, user_callback) + callback_sequence.after do |env| unless env.halted user_callback.call env.target, env.value end + env - } + end end private_class_method :halting - def self.conditional(next_callback, user_callback, user_conditions) - lambda { |env| - env = next_callback.call env + def self.conditional(callback_sequence, user_callback, user_conditions) + callback_sequence.after do |env| target = env.target value = env.value if user_conditions.all? { |c| c.call(target, value) } user_callback.call target, value end + env - } + end end private_class_method :conditional - def self.simple(next_callback, user_callback) - lambda { |env| - env = next_callback.call env + def self.simple(callback_sequence, user_callback) + callback_sequence.after do |env| user_callback.call env.target, env.value + env - } + end end private_class_method :simple end class Around - def self.build(next_callback, user_callback, user_conditions, chain_config) + def self.build(callback_sequence, user_callback, user_conditions, chain_config) if chain_config.key?(:terminator) && user_conditions.any? - halting_and_conditional(next_callback, user_callback, user_conditions) + halting_and_conditional(callback_sequence, user_callback, user_conditions) elsif chain_config.key? :terminator - halting(next_callback, user_callback) + halting(callback_sequence, user_callback) elsif user_conditions.any? - conditional(next_callback, user_callback, user_conditions) + conditional(callback_sequence, user_callback, user_conditions) else - simple(next_callback, user_callback) + simple(callback_sequence, user_callback) end end - def self.halting_and_conditional(next_callback, user_callback, user_conditions) - lambda { |env| + def self.halting_and_conditional(callback_sequence, user_callback, user_conditions) + callback_sequence.around do |env, &run| target = env.target value = env.value halted = env.halted if !halted && user_conditions.all? { |c| c.call(target, value) } user_callback.call(target, value) { - env = next_callback.call env - env.value + run.call.value } env else - next_callback.call env + run.call end - } + end end private_class_method :halting_and_conditional - def self.halting(next_callback, user_callback) - lambda { |env| + def self.halting(callback_sequence, user_callback) + callback_sequence.around do |env, &run| target = env.target value = env.value if env.halted - next_callback.call env + run.call else user_callback.call(target, value) { - env = next_callback.call env - env.value + run.call.value } env end - } + end end private_class_method :halting - def self.conditional(next_callback, user_callback, user_conditions) - lambda { |env| + def self.conditional(callback_sequence, user_callback, user_conditions) + callback_sequence.around do |env, &run| target = env.target value = env.value if user_conditions.all? { |c| c.call(target, value) } user_callback.call(target, value) { - env = next_callback.call env - env.value + run.call.value } env else - next_callback.call env + run.call end - } + end end private_class_method :conditional - def self.simple(next_callback, user_callback) - lambda { |env| + def self.simple(callback_sequence, user_callback) + callback_sequence.around do |env, &run| user_callback.call(env.target, env.value) { - env = next_callback.call env - env.value + run.call.value } env - } + end end private_class_method :simple end @@ -366,14 +368,14 @@ module ActiveSupport def filter; @key; end def raw_filter; @filter; end - def merge(chain, new_options) + def merge_conditional_options(chain, if_option:, unless_option:) options = { :if => @if.dup, :unless => @unless.dup } - options[:if].concat Array(new_options.fetch(:unless, [])) - options[:unless].concat Array(new_options.fetch(:if, [])) + options[:if].concat Array(unless_option) + options[:unless].concat Array(if_option) self.class.build chain, @filter, @kind, options end @@ -392,17 +394,17 @@ module ActiveSupport end # Wraps code with filter - def apply(next_callback) + def apply(callback_sequence) user_conditions = conditions_lambdas user_callback = make_lambda @filter case kind when :before - Filters::Before.build(next_callback, user_callback, user_conditions, chain_config, @filter) + Filters::Before.build(callback_sequence, user_callback, user_conditions, chain_config, @filter) when :after - Filters::After.build(next_callback, user_callback, user_conditions, chain_config) + Filters::After.build(callback_sequence, user_callback, user_conditions, chain_config) when :around - Filters::Around.build(next_callback, user_callback, user_conditions, chain_config) + Filters::Around.build(callback_sequence, user_callback, user_conditions, chain_config) end end @@ -467,16 +469,59 @@ module ActiveSupport end end + # Execute before and after filters in a sequence instead of + # chaining them with nested lambda calls, see: + # https://github.com/rails/rails/issues/18011 + class CallbackSequence + def initialize(&call) + @call = call + @before = [] + @after = [] + end + + def before(&before) + @before.unshift(before) + self + end + + def after(&after) + @after.push(after) + self + end + + def around(&around) + CallbackSequence.new do |*args| + around.call(*args) { + self.call(*args) + } + end + end + + def call(*args) + @before.each { |b| b.call(*args) } + value = @call.call(*args) + @after.each { |a| a.call(*args) } + value + end + end + # An Array with a compile method. class CallbackChain #:nodoc:# include Enumerable attr_reader :name, :config + # If true, any callback returning +false+ will halt the entire callback + # chain and display a deprecation message. If false, callback chains will + # only be halted by calling +throw :abort+. Defaults to +true+. + class_attribute :halt_and_display_warning_on_return_false + self.halt_and_display_warning_on_return_false = true + def initialize(name, config) @name = name @config = { - :scope => [ :kind ] + scope: [:kind], + terminator: default_terminator }.merge!(config) @chain = [] @callbacks = nil @@ -511,8 +556,9 @@ module ActiveSupport def compile @callbacks || @mutex.synchronize do - @callbacks ||= @chain.reverse.inject(Filters::ENDING) do |chain, callback| - callback.apply chain + final_sequence = CallbackSequence.new { |env| Filters::ENDING.call(env) } + @callbacks ||= @chain.reverse.inject(final_sequence) do |callback_sequence, callback| + callback.apply callback_sequence end end end @@ -546,6 +592,28 @@ module ActiveSupport @callbacks = nil @chain.delete_if { |c| callback.duplicates?(c) } end + + def default_terminator + Proc.new do |target, result_lambda| + terminate = true + catch(:abort) do + result = result_lambda.call if result_lambda.is_a?(Proc) + if halt_and_display_warning_on_return_false && result == false + display_deprecation_warning_for_false_terminator + else + terminate = false + end + end + terminate + end + end + + def display_deprecation_warning_for_false_terminator + ActiveSupport::Deprecation.warn(<<-MSG.squish) + Returning `false` in a callback will not implicitly halt a callback chain in the next release of Rails. + To explicitly halt a callback chain, please use `throw :abort` instead. + MSG + end end module ClassMethods @@ -628,7 +696,7 @@ module ActiveSupport filter = chain.find {|c| c.matches?(type, filter) } if filter && options.any? - new_filter = filter.merge(chain, options) + new_filter = filter.merge_conditional_options(chain, if_option: options[:if], unless_option: options[:unless]) chain.insert(chain.index(filter), new_filter) end @@ -659,21 +727,22 @@ module ActiveSupport # ===== Options # # * <tt>:terminator</tt> - Determines when a before filter will halt the - # callback chain, preventing following callbacks from being called and - # the event from being triggered. This should be a lambda to be executed. + # callback chain, preventing following before and around callbacks from + # being called and the event from being triggered. + # This should be a lambda to be executed. # The current object and the return result of the callback will be called # with the lambda. # # define_callbacks :validate, terminator: ->(target, result) { result == false } # # In this example, if any before validate callbacks returns +false+, - # other callbacks are not executed. Defaults to +false+, meaning no value - # halts the chain. + # any successive before and around callback is not executed. + # Defaults to +false+, meaning no value halts the chain. # # * <tt>:skip_after_callbacks_if_terminated</tt> - Determines if after # callbacks should be terminated by the <tt>:terminator</tt> option. By - # default after callbacks executed no matter if callback chain was - # terminated or not. Option makes sense only when <tt>:terminator</tt> + # default after callbacks are executed no matter if callback chain was + # terminated or not. This option makes sense only when <tt>:terminator</tt> # option is specified. # # * <tt>:scope</tt> - Indicates which methods should be executed when an |