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#
# Copyright (c) 2005-2012 David Heinemeier Hansson
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
#
# This is lifted from rails activesupport (note the copyright above):
# https://github.com/rails/rails/blob/9f84e60ac9d7bf07d6ae1bc94f3941f5b8f1a228/activesupport/lib/active_support/descendants_tracker.rb
class Chef
module Mixin
module DescendantsTracker
@@direct_descendants = {}
class << self
def direct_descendants(klass)
@@direct_descendants[klass] || []
end
def descendants(klass)
arr = []
accumulate_descendants(klass, arr)
arr
end
def find_descendants_by_name(klass, name)
descendants(klass).first {|c| c.name == name }
end
# This is the only method that is not thread safe, but is only ever called
# during the eager loading phase.
def store_inherited(klass, descendant)
(@@direct_descendants[klass] ||= []) << descendant
end
private
def accumulate_descendants(klass, acc)
if direct_descendants = @@direct_descendants[klass]
acc.concat(direct_descendants)
direct_descendants.each { |direct_descendant| accumulate_descendants(direct_descendant, acc) }
end
end
end
def inherited(base)
DescendantsTracker.store_inherited(self, base)
super
end
def direct_descendants
DescendantsTracker.direct_descendants(self)
end
def find_descendants_by_name(name)
DescendantsTracker.find_descendants_by_name(self, name)
end
def descendants
DescendantsTracker.descendants(self)
end
end
end
end
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