diff --git a/activesupport/lib/active_support/lazy_load_hooks.rb b/activesupport/lib/active_support/lazy_load_hooks.rb index c23b319046..c124416595 100644 --- a/activesupport/lib/active_support/lazy_load_hooks.rb +++ b/activesupport/lib/active_support/lazy_load_hooks.rb @@ -27,11 +27,17 @@ module ActiveSupport base.class_eval do @load_hooks = Hash.new { |h, k| h[k] = [] } @loaded = Hash.new { |h, k| h[k] = [] } + @run_once = Hash.new { |h, k| h[k] = [] } end end # Declares a block that will be executed when a Rails component is fully # loaded. + # + # Options: + # + # * :yield - Yields the object that run_load_hooks to +block+. + # * :run_once - Given +block+ will run only once. def on_load(name, options = {}, &block) @loaded[name].each do |base| execute_hook(base, options, block) @@ -40,20 +46,32 @@ module ActiveSupport @load_hooks[name] << [block, options] end - def execute_hook(base, options, block) - if options[:yield] - block.call(base) - else - base.instance_eval(&block) - end - end - def run_load_hooks(name, base = Object) @loaded[name] << base @load_hooks[name].each do |hook, options| execute_hook(base, options, hook) end end + + private + + def with_execution_control(name, block, once) + unless @run_once[name].include?(block) + @run_once[name] << block if once + + yield + end + end + + def execute_hook(base, options, block) + with_execution_control(name, block, options[:run_once]) do + if options[:yield] + block.call(base) + else + base.instance_eval(&block) + end + end + end end extend LazyLoadHooks diff --git a/activesupport/test/lazy_load_hooks_test.rb b/activesupport/test/lazy_load_hooks_test.rb index 9c9264e8fc..c161005100 100644 --- a/activesupport/test/lazy_load_hooks_test.rb +++ b/activesupport/test/lazy_load_hooks_test.rb @@ -20,6 +20,18 @@ class LazyLoadHooksTest < ActiveSupport::TestCase assert_equal 7, i end + def test_basic_hook_with_two_registrations_only_once + i = 0 + ActiveSupport.on_load(:basic_hook_with_two_once, run_once: true) do + i += incr + end + assert_equal 0, i + ActiveSupport.run_load_hooks(:basic_hook_with_two_once, FakeContext.new(2)) + assert_equal 2, i + ActiveSupport.run_load_hooks(:basic_hook_with_two_once, FakeContext.new(5)) + assert_equal 2, i + end + def test_hook_registered_after_run i = 0 ActiveSupport.run_load_hooks(:registered_after) @@ -37,6 +49,15 @@ class LazyLoadHooksTest < ActiveSupport::TestCase assert_equal 7, i end + def test_hook_registered_after_run_with_two_registrations_only_once + i = 0 + ActiveSupport.run_load_hooks(:registered_after_with_two_once, FakeContext.new(2)) + ActiveSupport.run_load_hooks(:registered_after_with_two_once, FakeContext.new(5)) + assert_equal 0, i + ActiveSupport.on_load(:registered_after_with_two_once, run_once: true) { i += incr } + assert_equal 2, i + end + def test_hook_registered_interleaved_run_with_two_registrations i = 0 ActiveSupport.run_load_hooks(:registered_interleaved_with_two, FakeContext.new(2)) @@ -47,6 +68,22 @@ class LazyLoadHooksTest < ActiveSupport::TestCase assert_equal 7, i end + def test_hook_registered_interleaved_run_with_two_registrations_once + i = 0 + ActiveSupport + .run_load_hooks(:registered_interleaved_with_two_once, FakeContext.new(2)) + assert_equal 0, i + + ActiveSupport.on_load(:registered_interleaved_with_two_once, run_once: true) do + i += incr + end + assert_equal 2, i + + ActiveSupport + .run_load_hooks(:registered_interleaved_with_two_once, FakeContext.new(5)) + assert_equal 2, i + end + def test_hook_receives_a_context i = 0 ActiveSupport.on_load(:contextual) { i += incr }