callbacks.rb in activesupport-7.1.0.beta1

- old
+ new

@@ -7,11 +7,13 @@
 require "active_support/core_ext/string/filters"
 require "active_support/core_ext/object/blank"
 require "thread"
 
 module ActiveSupport
-  # Callbacks are code hooks that are run at key points in an object's life cycle.
+  # = Active Support \Callbacks
+  #
+  # \Callbacks are code hooks that are run at key points in an object's life cycle.
   # 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.
   #
@@ -66,11 +68,11 @@
     included do
       extend ActiveSupport::DescendantsTracker
       class_attribute :__callbacks, instance_writer: false, default: {}
     end
 
-    CALLBACK_FILTER_TYPES = [:before, :after, :around]
+    CALLBACK_FILTER_TYPES = [:before, :after, :around].freeze
 
     # 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
@@ -90,19 +92,20 @@
     # user code, it has an additional design goal of minimizing its impact on
     # the visible call stack. An exception from inside a :before or :after
     # callback can be as noisy as it likes -- but when control has passed
     # smoothly through and into the supplied block, we want as little evidence
     # as possible that we were here.
-    def run_callbacks(kind)
+    def run_callbacks(kind, type = nil)
       callbacks = __callbacks[kind.to_sym]
 
       if callbacks.empty?
         yield if block_given?
       else
         env = Filters::Environment.new(self, false, nil)
-        next_sequence = callbacks.compile
 
+        next_sequence = callbacks.compile(type)
+
         # Common case: no 'around' callbacks defined
         if next_sequence.final?
           next_sequence.invoke_before(env)
           env.value = !env.halted && (!block_given? || yield)
           next_sequence.invoke_after(env)
@@ -610,46 +613,60 @@
           @config = {
             scope: [:kind],
             terminator: default_terminator
           }.merge!(config)
           @chain = []
-          @callbacks = nil
+          @all_callbacks = nil
+          @single_callbacks = {}
           @mutex = Mutex.new
         end
 
         def each(&block); @chain.each(&block); end
         def index(o);     @chain.index(o); end
         def empty?;       @chain.empty?; end
 
         def insert(index, o)
-          @callbacks = nil
+          @all_callbacks = nil
+          @single_callbacks.clear
           @chain.insert(index, o)
         end
 
         def delete(o)
-          @callbacks = nil
+          @all_callbacks = nil
+          @single_callbacks.clear
           @chain.delete(o)
         end
 
         def clear
-          @callbacks = nil
+          @all_callbacks = nil
+          @single_callbacks.clear
           @chain.clear
           self
         end
 
         def initialize_copy(other)
-          @callbacks = nil
+          @all_callbacks = nil
+          @single_callbacks = {}
           @chain     = other.chain.dup
           @mutex     = Mutex.new
         end
 
-        def compile
-          @callbacks || @mutex.synchronize do
-            final_sequence = CallbackSequence.new
-            @callbacks ||= @chain.reverse.inject(final_sequence) do |callback_sequence, callback|
-              callback.apply callback_sequence
+        def compile(type)
+          if type.nil?
+            @all_callbacks || @mutex.synchronize do
+              final_sequence = CallbackSequence.new
+              @all_callbacks ||= @chain.reverse.inject(final_sequence) do |callback_sequence, callback|
+                callback.apply(callback_sequence)
+              end
             end
+          else
+            @single_callbacks[type] || @mutex.synchronize do
+              final_sequence = CallbackSequence.new
+              @single_callbacks[type] ||= @chain.reverse.inject(final_sequence) do |callback_sequence, callback|
+                type == callback.kind ? callback.apply(callback_sequence) : callback_sequence
+              end
+            end
           end
         end
 
         def append(*callbacks)
           callbacks.each { |c| append_one(c) }
@@ -662,23 +679,26 @@
         protected
           attr_reader :chain
 
         private
           def append_one(callback)
-            @callbacks = nil
+            @all_callbacks = nil
+            @single_callbacks.clear
             remove_duplicates(callback)
             @chain.push(callback)
           end
 
           def prepend_one(callback)
-            @callbacks = nil
+            @all_callbacks = nil
+            @single_callbacks.clear
             remove_duplicates(callback)
             @chain.unshift(callback)
           end
 
           def remove_duplicates(callback)
-            @callbacks = nil
+            @all_callbacks = nil
+            @single_callbacks.clear
             @chain.delete_if { |c| callback.duplicates?(c) }
           end
 
           def default_terminator
             Proc.new do |target, result_lambda|
@@ -701,10 +721,10 @@
         end
 
         # This is used internally to append, prepend and skip callbacks to the
         # CallbackChain.
         def __update_callbacks(name) # :nodoc:
-          ([self] + self.descendants).reverse_each do |target|
+          self.descendants.prepend(self).reverse_each do |target|
             chain = target.get_callbacks name
             yield target, chain.dup
           end
         end
 