Add bin and edit workflow

bin/gems/concurrent-ruby-1.3.8/lib/concurrent-ruby/concurrent/dataflow.rb

@@ -0,0 +1,81 @@
+require 'concurrent/future'
+require 'concurrent/atomic/atomic_fixnum'
+
+module Concurrent
+
+  # @!visibility private
+  class DependencyCounter # :nodoc:
+
+    def initialize(count, &block)
+      @counter = AtomicFixnum.new(count)
+      @block = block
+    end
+
+    def update(time, value, reason)
+      if @counter.decrement == 0
+        @block.call
+      end
+    end
+  end
+
+  # Dataflow allows you to create a task that will be scheduled when all of its data dependencies are available.
+  # {include:file:docs-source/dataflow.md}
+  #
+  # @param [Future] inputs zero or more `Future` operations that this dataflow depends upon
+  #
+  # @yield The operation to perform once all the dependencies are met
+  # @yieldparam [Future] inputs each of the `Future` inputs to the dataflow
+  # @yieldreturn [Object] the result of the block operation
+  #
+  # @return [Object] the result of all the operations
+  #
+  # @raise [ArgumentError] if no block is given
+  # @raise [ArgumentError] if any of the inputs are not `IVar`s
+  def dataflow(*inputs, &block)
+    dataflow_with(Concurrent.global_io_executor, *inputs, &block)
+  end
+  module_function :dataflow
+
+  def dataflow_with(executor, *inputs, &block)
+    call_dataflow(:value, executor, *inputs, &block)
+  end
+  module_function :dataflow_with
+
+  def dataflow!(*inputs, &block)
+    dataflow_with!(Concurrent.global_io_executor, *inputs, &block)
+  end
+  module_function :dataflow!
+
+  def dataflow_with!(executor, *inputs, &block)
+    call_dataflow(:value!, executor, *inputs, &block)
+  end
+  module_function :dataflow_with!
+
+  private
+
+  def call_dataflow(method, executor, *inputs, &block)
+    raise ArgumentError.new('an executor must be provided') if executor.nil?
+    raise ArgumentError.new('no block given') unless block_given?
+    unless inputs.all? { |input| input.is_a? IVar }
+      raise ArgumentError.new("Not all dependencies are IVars.\nDependencies: #{ inputs.inspect }")
+    end
+
+    result = Future.new(executor: executor) do
+      values = inputs.map { |input| input.send(method) }
+      block.call(*values)
+    end
+
+    if inputs.empty?
+      result.execute
+    else
+      counter = DependencyCounter.new(inputs.size) { result.execute }
+
+      inputs.each do |input|
+        input.add_observer counter
+      end
+    end
+
+    result
+  end
+  module_function :call_dataflow
+end