lib/active_support/callbacks.rb in activesupport-3.2.22.5 vs lib/active_support/callbacks.rb in activesupport-4.0.0.beta1
- old
+ new
@@ -1,33 +1,32 @@
+require 'thread_safe'
require 'active_support/concern'
require 'active_support/descendants_tracker'
-require 'active_support/core_ext/array/wrap'
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/object/inclusion'
module ActiveSupport
- # \Callbacks are code hooks that are run at key points in an object's lifecycle.
- # The typical use case is to have a base class define a set of callbacks relevant
- # to the other functionality it supplies, so that subclasses can install callbacks
- # that enhance or modify the base functionality without needing to override
- # or redefine methods of the base class.
+ # Callbacks are code hooks that are run at key points in an object's lifecycle.
+ # The typical use case is to have a base class define a set of callbacks
+ # relevant to the other functionality it supplies, so that subclasses can
+ # install callbacks that enhance or modify the base functionality without
+ # needing to override or redefine methods of the base class.
#
- # Mixing in this module allows you to define the events in the object's lifecycle
- # that will support callbacks (via +ClassMethods.define_callbacks+), set the instance
- # methods, procs, or callback objects to be called (via +ClassMethods.set_callback+),
- # and run the installed callbacks at the appropriate times (via +run_callbacks+).
+ # Mixing in this module allows you to define the events in the object's
+ # lifecycle that will support callbacks (via +ClassMethods.define_callbacks+),
+ # set the instance methods, procs, or callback objects to be called (via
+ # +ClassMethods.set_callback+), and run the installed callbacks at the
+ # appropriate times (via +run_callbacks+).
#
- # Three kinds of callbacks are supported: before callbacks, run before a certain event;
- # after callbacks, run after the event; and around callbacks, blocks that surround the
- # event, triggering it when they yield. Callback code can be contained in instance
- # methods, procs or lambdas, or callback objects that respond to certain predetermined
- # methods. See +ClassMethods.set_callback+ for details.
+ # Three kinds of callbacks are supported: before callbacks, run before a
+ # certain event; after callbacks, run after the event; and around callbacks,
+ # blocks that surround the event, triggering it when they yield. Callback code
+ # can be contained in instance methods, procs or lambdas, or callback objects
+ # that respond to certain predetermined methods. See +ClassMethods.set_callback+
+ # for details.
#
- # ==== Example
- #
# class Record
# include ActiveSupport::Callbacks
# define_callbacks :save
#
# def save
@@ -53,82 +52,76 @@
#
# Output:
# saving...
# - save
# saved
- #
module Callbacks
extend Concern
included do
extend ActiveSupport::DescendantsTracker
end
# Runs the callbacks for the given event.
#
# Calls the before and around callbacks in the order they were set, yields
- # the block (if given one), and then runs the after callbacks in reverse order.
- # Optionally accepts a key, which will be used to compile an optimized callback
- # method for each key. See +ClassMethods.define_callbacks+ for more information.
+ # the block (if given one), and then runs the after callbacks in reverse
+ # order.
#
- # If the callback chain was halted, returns +false+. Otherwise returns the result
- # of the block, or +true+ if no block is given.
+ # If the callback chain was halted, returns +false+. Otherwise returns the
+ # result of the block, or +true+ if no block is given.
#
# run_callbacks :save do
# save
# end
- #
- def run_callbacks(kind, *args, &block)
- send("_run_#{kind}_callbacks", *args, &block)
+ def run_callbacks(kind, &block)
+ runner_name = self.class.__define_callbacks(kind, self)
+ send(runner_name, &block)
end
private
# A hook invoked everytime a before callback is halted.
- # This can be overriden in AS::Callback implementors in order
+ # This can be overridden in AS::Callback implementors in order
# to provide better debugging/logging.
def halted_callback_hook(filter)
end
class Callback #:nodoc:#
@@_callback_sequence = 0
- attr_accessor :chain, :filter, :kind, :options, :per_key, :klass, :raw_filter
+ attr_accessor :chain, :filter, :kind, :options, :klass, :raw_filter
def initialize(chain, filter, kind, options, klass)
@chain, @kind, @klass = chain, kind, klass
+ deprecate_per_key_option(options)
normalize_options!(options)
- @per_key = options.delete(:per_key)
@raw_filter, @options = filter, options
@filter = _compile_filter(filter)
- @compiled_options = _compile_options(options)
- @callback_id = next_id
+ recompile_options!
+ end
- _compile_per_key_options
+ def deprecate_per_key_option(options)
+ if options[:per_key]
+ raise NotImplementedError, ":per_key option is no longer supported. Use generic :if and :unless options instead."
+ end
end
def clone(chain, klass)
obj = super()
obj.chain = chain
obj.klass = klass
- obj.per_key = @per_key.dup
obj.options = @options.dup
- obj.per_key[:if] = @per_key[:if].dup
- obj.per_key[:unless] = @per_key[:unless].dup
obj.options[:if] = @options[:if].dup
obj.options[:unless] = @options[:unless].dup
obj
end
def normalize_options!(options)
- options[:if] = Array.wrap(options[:if])
- options[:unless] = Array.wrap(options[:unless])
-
- options[:per_key] ||= {}
- options[:per_key][:if] = Array.wrap(options[:per_key][:if])
- options[:per_key][:unless] = Array.wrap(options[:per_key][:unless])
+ options[:if] = Array(options[:if])
+ options[:unless] = Array(options[:unless])
end
def name
chain.name
end
@@ -139,48 +132,30 @@
def matches?(_kind, _filter)
@kind == _kind && @filter == _filter
end
+ def duplicates?(other)
+ matches?(other.kind, other.filter)
+ end
+
def _update_filter(filter_options, new_options)
- filter_options[:if].push(new_options[:unless]) if new_options.key?(:unless)
- filter_options[:unless].push(new_options[:if]) if new_options.key?(:if)
+ filter_options[:if].concat(Array(new_options[:unless])) if new_options.key?(:unless)
+ filter_options[:unless].concat(Array(new_options[:if])) if new_options.key?(:if)
end
- def recompile!(_options, _per_key)
+ def recompile!(_options)
+ deprecate_per_key_option(_options)
_update_filter(self.options, _options)
- _update_filter(self.per_key, _per_key)
- @callback_id = next_id
- @filter = _compile_filter(@raw_filter)
- @compiled_options = _compile_options(@options)
- _compile_per_key_options
+ recompile_options!
end
- def _compile_per_key_options
- key_options = _compile_options(@per_key)
-
- @klass.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
- def _one_time_conditions_valid_#{@callback_id}?
- true if #{key_options}
- end
- RUBY_EVAL
- end
-
- # This will supply contents for before and around filters, and no
- # contents for after filters (for the forward pass).
- def start(key=nil, object=nil)
- return if key && !object.send("_one_time_conditions_valid_#{@callback_id}?")
-
- # options[0] is the compiled form of supplied conditions
- # options[1] is the "end" for the conditional
- #
+ # Wraps code with filter
+ def apply(code)
case @kind
when :before
- # if condition # before_save :filter_name, :if => :condition
- # filter_name
- # end
<<-RUBY_EVAL
if !halted && #{@compiled_options}
# This double assignment is to prevent warnings in 1.9.3 as
# the `result` variable is not always used except if the
# terminator code refers to it.
@@ -188,104 +163,99 @@
halted = (#{chain.config[:terminator]})
if halted
halted_callback_hook(#{@raw_filter.inspect.inspect})
end
end
+ #{code}
RUBY_EVAL
- when :around
- # Compile around filters with conditions into proxy methods
- # that contain the conditions.
- #
- # For `around_save :filter_name, :if => :condition':
- #
- # def _conditional_callback_save_17
- # if condition
- # filter_name do
- # yield self
- # end
- # else
- # yield self
- # end
- # end
- #
- name = "_conditional_callback_#{@kind}_#{next_id}"
- @klass.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
- def #{name}(halted)
- if #{@compiled_options} && !halted
- #{@filter} do
- yield self
- end
- else
- yield self
- end
- end
- RUBY_EVAL
- "#{name}(halted) do"
- end
- end
-
- # This will supply contents for around and after filters, but not
- # before filters (for the backward pass).
- def end(key=nil, object=nil)
- return if key && !object.send("_one_time_conditions_valid_#{@callback_id}?")
-
- case @kind
when :after
- # after_save :filter_name, :if => :condition
<<-RUBY_EVAL
- if #{@compiled_options}
+ #{code}
+ if #{!chain.config[:skip_after_callbacks_if_terminated] || "!halted"} && #{@compiled_options}
#{@filter}
end
RUBY_EVAL
when :around
+ name = define_conditional_callback
<<-RUBY_EVAL
+ #{name}(halted) do
+ #{code}
value
end
RUBY_EVAL
end
end
private
+ # Compile around filters with conditions into proxy methods
+ # that contain the conditions.
+ #
+ # For `set_callback :save, :around, :filter_name, if: :condition':
+ #
+ # def _conditional_callback_save_17
+ # if condition
+ # filter_name do
+ # yield self
+ # end
+ # else
+ # yield self
+ # end
+ # end
+ def define_conditional_callback
+ name = "_conditional_callback_#{@kind}_#{next_id}"
+ @klass.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
+ def #{name}(halted)
+ if #{@compiled_options} && !halted
+ #{@filter} do
+ yield self
+ end
+ else
+ yield self
+ end
+ end
+ RUBY_EVAL
+ name
+ end
+
# Options support the same options as filters themselves (and support
# symbols, string, procs, and objects), so compile a conditional
- # expression based on the options
- def _compile_options(options)
+ # expression based on the options.
+ def recompile_options!
conditions = ["true"]
unless options[:if].empty?
- conditions << Array.wrap(_compile_filter(options[:if]))
+ conditions << Array(_compile_filter(options[:if]))
end
unless options[:unless].empty?
- conditions << Array.wrap(_compile_filter(options[:unless])).map {|f| "!#{f}"}
+ conditions << Array(_compile_filter(options[:unless])).map {|f| "!#{f}"}
end
- conditions.flatten.join(" && ")
+ @compiled_options = conditions.flatten.join(" && ")
end
# Filters support:
#
# Arrays:: Used in conditions. This is used to specify
# multiple conditions. Used internally to
- # merge conditions from skip_* filters
- # Symbols:: A method to call
- # Strings:: Some content to evaluate
- # Procs:: A proc to call with the object
- # Objects:: An object with a before_foo method on it to call
+ # merge conditions from skip_* filters.
+ # Symbols:: A method to call.
+ # Strings:: Some content to evaluate.
+ # Procs:: A proc to call with the object.
+ # Objects:: An object with a <tt>before_foo</tt> method on it to call.
#
# All of these objects are compiled into methods and handled
# the same after this point:
#
- # Arrays:: Merged together into a single filter
- # Symbols:: Already methods
- # Strings:: class_eval'ed into methods
- # Procs:: define_method'ed into methods
+ # Arrays:: Merged together into a single filter.
+ # Symbols:: Already methods.
+ # Strings:: class_eval'ed into methods.
+ # Procs:: define_method'ed into methods.
# Objects::
# a method is created that calls the before_foo method
# on the object.
- #
def _compile_filter(filter)
method_name = "_callback_#{@kind}_#{next_id}"
case filter
when Array
filter.map {|f| _compile_filter(f)}
@@ -300,11 +270,11 @@
method_name << (filter.arity == 1 ? "(self)" : " self, Proc.new ")
else
@klass.send(:define_method, "#{method_name}_object") { filter }
_normalize_legacy_filter(kind, filter)
- scopes = Array.wrap(chain.config[:scope])
+ scopes = Array(chain.config[:scope])
method_to_call = scopes.map{ |s| s.is_a?(Symbol) ? send(s) : s }.join("_")
@klass.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
def #{method_name}(&blk)
#{method_name}_object.send(:#{method_to_call}, self, &blk)
@@ -315,112 +285,119 @@
end
end
def _normalize_legacy_filter(kind, filter)
if !filter.respond_to?(kind) && filter.respond_to?(:filter)
+ message = "Filter object with #filter method is deprecated. Define method corresponding " \
+ "to filter type (#before, #after or #around)."
+ ActiveSupport::Deprecation.warn message
filter.singleton_class.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
def #{kind}(context, &block) filter(context, &block) end
RUBY_EVAL
- elsif filter.respond_to?(:before) && filter.respond_to?(:after) && kind == :around
+ elsif filter.respond_to?(:before) && filter.respond_to?(:after) && kind == :around && !filter.respond_to?(:around)
+ message = "Filter object with #before and #after methods is deprecated. Define #around method instead."
+ ActiveSupport::Deprecation.warn message
def filter.around(context)
should_continue = before(context)
yield if should_continue
after(context)
end
end
end
end
- # An Array with a compile method
+ # An Array with a compile method.
class CallbackChain < Array #:nodoc:#
attr_reader :name, :config
def initialize(name, config)
@name = name
@config = {
:terminator => "false",
- :rescuable => false,
:scope => [ :kind ]
}.merge(config)
end
- def compile(key=nil, object=nil)
+ def compile
method = []
method << "value = nil"
method << "halted = false"
- each do |callback|
- method << callback.start(key, object)
+ callbacks = "value = !halted && (!block_given? || yield)"
+ reverse_each do |callback|
+ callbacks = callback.apply(callbacks)
end
+ method << callbacks
- if config[:rescuable]
- method << "rescued_error = nil"
- method << "begin"
- end
+ method << "value"
+ method.join("\n")
+ end
- method << "value = yield if block_given? && !halted"
+ def append(*callbacks)
+ callbacks.each { |c| append_one(c) }
+ end
- if config[:rescuable]
- method << "rescue Exception => e"
- method << "rescued_error = e"
- method << "end"
- end
+ def prepend(*callbacks)
+ callbacks.each { |c| prepend_one(c) }
+ end
- reverse_each do |callback|
- method << callback.end(key, object)
- end
+ private
- method << "raise rescued_error if rescued_error" if config[:rescuable]
- method << "halted ? false : (block_given? ? value : true)"
- method.compact.join("\n")
+ def append_one(callback)
+ remove_duplicates(callback)
+ push(callback)
end
+
+ def prepend_one(callback)
+ remove_duplicates(callback)
+ unshift(callback)
+ end
+
+ def remove_duplicates(callback)
+ delete_if { |c| callback.duplicates?(c) }
+ end
+
end
module ClassMethods
- # Generate the internal runner method called by +run_callbacks+.
- def __define_runner(symbol) #:nodoc:
- runner_method = "_run_#{symbol}_callbacks"
- unless private_method_defined?(runner_method)
- class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
- def #{runner_method}(key = nil, &blk)
- self.class.__run_callback(key, :#{symbol}, self, &blk)
- end
- private :#{runner_method}
- RUBY_EVAL
- end
- end
- # This method calls the callback method for the given key.
- # If this called first time it creates a new callback method for the key,
- # calculating which callbacks can be omitted because of per_key conditions.
- #
- def __run_callback(key, kind, object, &blk) #:nodoc:
- name = __callback_runner_name(key, kind)
+ # This method defines callback chain method for the given kind
+ # if it was not yet defined.
+ # This generated method plays caching role.
+ def __define_callbacks(kind, object) #:nodoc:
+ name = __callback_runner_name(kind)
unless object.respond_to?(name, true)
- str = object.send("_#{kind}_callbacks").compile(key, object)
+ str = object.send("_#{kind}_callbacks").compile
class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
def #{name}() #{str} end
protected :#{name}
RUBY_EVAL
end
- object.send(name, &blk)
+ name
end
def __reset_runner(symbol)
- name = __callback_runner_name(nil, symbol)
+ name = __callback_runner_name(symbol)
undef_method(name) if method_defined?(name)
end
- def __callback_runner_name(key, kind)
- "_run__#{self.name.hash.abs}__#{kind}__#{key.hash.abs}__callbacks"
+ def __callback_runner_name_cache
+ @__callback_runner_name_cache ||= ThreadSafe::Cache.new {|cache, kind| cache[kind] = __generate_callback_runner_name(kind) }
end
+ def __generate_callback_runner_name(kind)
+ "_run__#{self.name.hash.abs}__#{kind}__callbacks"
+ end
+
+ def __callback_runner_name(kind)
+ __callback_runner_name_cache[kind]
+ end
+
# This is used internally to append, prepend and skip callbacks to the
# CallbackChain.
- #
def __update_callbacks(name, filters = [], block = nil) #:nodoc:
- type = filters.first.in?([:before, :after, :around]) ? filters.shift : :before
+ type = [:before, :after, :around].include?(filters.first) ? filters.shift : :before
options = filters.last.is_a?(Hash) ? filters.pop : {}
filters.unshift(block) if block
([self] + ActiveSupport::DescendantsTracker.descendants(self)).reverse.each do |target|
chain = target.send("_#{name}_callbacks")
@@ -430,110 +407,81 @@
end
# Install a callback for the given event.
#
# set_callback :save, :before, :before_meth
- # set_callback :save, :after, :after_meth, :if => :condition
- # set_callback :save, :around, lambda { |r| stuff; result = yield; stuff }
+ # set_callback :save, :after, :after_meth, if: :condition
+ # set_callback :save, :around, ->(r, &block) { stuff; result = block.call; stuff }
#
# The second arguments indicates whether the callback is to be run +:before+,
# +:after+, or +:around+ the event. If omitted, +:before+ is assumed. This
# means the first example above can also be written as:
#
# set_callback :save, :before_meth
#
- # The callback can specified as a symbol naming an instance method; as a proc,
- # lambda, or block; as a string to be instance evaluated; or as an object that
- # responds to a certain method determined by the <tt>:scope</tt> argument to
- # +define_callback+.
+ # The callback can specified as a symbol naming an instance method; as a
+ # proc, lambda, or block; as a string to be instance evaluated; or as an
+ # object that responds to a certain method determined by the <tt>:scope</tt>
+ # argument to +define_callback+.
#
# If a proc, lambda, or block is given, its body is evaluated in the context
# of the current object. It can also optionally accept the current object as
# an argument.
#
- # Before and around callbacks are called in the order that they are set; after
- # callbacks are called in the reverse order.
- #
+ # Before and around callbacks are called in the order that they are set;
+ # after callbacks are called in the reverse order.
+ #
# Around callbacks can access the return value from the event, if it
# wasn't halted, from the +yield+ call.
#
# ===== Options
#
- # * <tt>:if</tt> - A symbol naming an instance method or a proc; the callback
- # will be called only when it returns a true value.
- # * <tt>:unless</tt> - A symbol naming an instance method or a proc; the callback
- # will be called only when it returns a false value.
- # * <tt>:prepend</tt> - If true, the callback will be prepended to the existing
- # chain rather than appended.
- # * <tt>:per_key</tt> - A hash with <tt>:if</tt> and <tt>:unless</tt> options;
- # see "Per-key conditions" below.
- #
- # ===== Per-key conditions
- #
- # When creating or skipping callbacks, you can specify conditions that
- # are always the same for a given key. For instance, in Action Pack,
- # we convert :only and :except conditions into per-key conditions.
- #
- # before_filter :authenticate, :except => "index"
- #
- # becomes
- #
- # set_callback :process_action, :before, :authenticate, :per_key => {:unless => proc {|c| c.action_name == "index"}}
- #
- # Per-key conditions are evaluated only once per use of a given key.
- # In the case of the above example, you would do:
- #
- # run_callbacks(:process_action, action_name) { ... dispatch stuff ... }
- #
- # In that case, each action_name would get its own compiled callback
- # method that took into consideration the per_key conditions. This
- # is a speed improvement for ActionPack.
- #
+ # * <tt>:if</tt> - A symbol naming an instance method or a proc; the
+ # callback will be called only when it returns a +true+ value.
+ # * <tt>:unless</tt> - A symbol naming an instance method or a proc; the
+ # callback will be called only when it returns a +false+ value.
+ # * <tt>:prepend</tt> - If +true+, the callback will be prepended to the
+ # existing chain rather than appended.
def set_callback(name, *filter_list, &block)
mapped = nil
__update_callbacks(name, filter_list, block) do |target, chain, type, filters, options|
mapped ||= filters.map do |filter|
Callback.new(chain, filter, type, options.dup, self)
end
- filters.each do |filter|
- chain.delete_if {|c| c.matches?(type, filter) }
- end
+ options[:prepend] ? chain.prepend(*mapped) : chain.append(*mapped)
- options[:prepend] ? chain.unshift(*(mapped.reverse)) : chain.push(*mapped)
-
target.send("_#{name}_callbacks=", chain)
end
end
- # Skip a previously set callback. Like +set_callback+, <tt>:if</tt> or <tt>:unless</tt>
- # options may be passed in order to control when the callback is skipped.
+ # Skip a previously set callback. Like +set_callback+, <tt>:if</tt> or
+ # <tt>:unless</tt> options may be passed in order to control when the
+ # callback is skipped.
#
# class Writer < Person
- # skip_callback :validate, :before, :check_membership, :if => lambda { self.age > 18 }
+ # skip_callback :validate, :before, :check_membership, if: -> { self.age > 18 }
# end
- #
def skip_callback(name, *filter_list, &block)
__update_callbacks(name, filter_list, block) do |target, chain, type, filters, options|
filters.each do |filter|
filter = chain.find {|c| c.matches?(type, filter) }
if filter && options.any?
new_filter = filter.clone(chain, self)
chain.insert(chain.index(filter), new_filter)
- new_filter.recompile!(options, options[:per_key] || {})
+ new_filter.recompile!(options)
end
chain.delete(filter)
end
target.send("_#{name}_callbacks=", chain)
end
end
# Remove all set callbacks for the given event.
- #
def reset_callbacks(symbol)
callbacks = send("_#{symbol}_callbacks")
ActiveSupport::DescendantsTracker.descendants(self).each do |target|
chain = target.send("_#{symbol}_callbacks").dup
@@ -552,28 +500,29 @@
# define_callbacks :validate
# define_callbacks :initialize, :save, :destroy
#
# ===== 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 is a string to be eval'ed. The result of the callback is available
- # in the <tt>result</tt> variable.
+ # * <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 is a string to be eval'ed. The
+ # result of the callback is available in the +result+ variable.
#
- # define_callbacks :validate, :terminator => "result == false"
+ # define_callbacks :validate, terminator: 'result == false'
#
# In this example, if any before validate callbacks returns +false+,
- # other callbacks are not executed. Defaults to "false", meaning no value
+ # other callbacks are not executed. Defaults to +false+, meaning no value
# halts the chain.
#
- # * <tt>:rescuable</tt> - By default, after filters are not executed if
- # the given block or a before filter raises an error. By setting this option
- # to <tt>true</tt> exception raised by given block is stored and after
- # executing all the after callbacks the stored exception is raised.
+ # * <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>
+ # option is specified.
#
- # * <tt>:scope</tt> - Indicates which methods should be executed when an object
- # is used as a callback.
+ # * <tt>:scope</tt> - Indicates which methods should be executed when an
+ # object is used as a callback.
#
# class Audit
# def before(caller)
# puts 'Audit: before is called'
# end
@@ -594,32 +543,31 @@
# puts 'save in main'
# end
# end
# end
#
- # In the above case whenever you save an account the method <tt>Audit#before</tt> will
- # be called. On the other hand
+ # In the above case whenever you save an account the method
+ # <tt>Audit#before</tt> will be called. On the other hand
#
- # define_callbacks :save, :scope => [:kind, :name]
+ # define_callbacks :save, scope: [:kind, :name]
#
- # would trigger <tt>Audit#before_save</tt> instead. That's constructed by calling
- # <tt>#{kind}_#{name}</tt> on the given instance. In this case "kind" is "before" and
- # "name" is "save". In this context +:kind+ and +:name+ have special meanings: +:kind+
- # refers to the kind of callback (before/after/around) and +:name+ refers to the
- # method on which callbacks are being defined.
+ # would trigger <tt>Audit#before_save</tt> instead. That's constructed
+ # by calling <tt>#{kind}_#{name}</tt> on the given instance. In this
+ # case "kind" is "before" and "name" is "save". In this context +:kind+
+ # and +:name+ have special meanings: +:kind+ refers to the kind of
+ # callback (before/after/around) and +:name+ refers to the method on
+ # which callbacks are being defined.
#
# A declaration like
#
- # define_callbacks :save, :scope => [:name]
+ # define_callbacks :save, scope: [:name]
#
# would call <tt>Audit#save</tt>.
- #
def define_callbacks(*callbacks)
config = callbacks.last.is_a?(Hash) ? callbacks.pop : {}
callbacks.each do |callback|
class_attribute "_#{callback}_callbacks"
send("_#{callback}_callbacks=", CallbackChain.new(callback, config))
- __define_runner(callback)
end
end
end
end
end