parallel out, concurrent-ruby in

Gemfile.lock

@@ -3,13 +3,13 @@ PATH
   specs:
     steep (1.4.0.dev.4)
       activesupport (>= 5.1)
+      concurrent-ruby (>= 1.2.2)
       csv (>= 3.0.9)
       fileutils (>= 1.1.0)
       json (>= 2.1.0)
       language_server-protocol (>= 3.15, < 4.0)
       listen (~> 3.0)
       logger (>= 1.3.0)
-      parallel (>= 1.0.0)
       parser (>= 3.1)
       rainbow (>= 2.2.2, < 4.0)
       rbs (>= 2.8.0)
@@ -46,7 +46,6 @@ GEM
       minitest (> 5.3)
     minitest-slow_test (0.2.0)
       minitest (>= 5.0)
-    parallel (1.23.0)
     parser (3.2.2.0)
       ast (~> 2.4.1)
     rainbow (3.1.1)

lib/steep.rb

@@ -16,7 +16,7 @@
 require "yaml"
 require "securerandom"
 
-require "parallel/processor_count"
+require "concurrent/utility/processor_counter"
 require "terminal-table"
 
 require "rbs"

lib/steep/cli.rb

@@ -8,8 +8,6 @@ class CLI
     attr_reader :stderr
     attr_reader :command
 
-    include Parallel::ProcessorCount
-
     def initialize(stdout:, stdin:, stderr:, argv:)
       @stdout = stdout
       @stdin = stdin

lib/steep/drivers/utils/jobs_option.rb

@@ -4,14 +4,12 @@ module Utils
       class JobsOption
         attr_accessor :jobs_count, :steep_command, :jobs_count_modifier
 
-        include Parallel::ProcessorCount
-
         def initialize(jobs_count_modifier: 0)
           @jobs_count_modifier = jobs_count_modifier
         end
 
         def default_jobs_count
-          physical_processor_count + jobs_count_modifier
+          Concurrent.physical_processor_count + jobs_count_modifier
         end
 
         def jobs_count_value

sig/shims/concurrent-ruby.rbs

@@ -0,0 +1,39 @@
+module Concurrent
+  # Number of physical processor cores on the current system. For performance
+  # reasons the calculated value will be memoized on the first call.
+  #
+  # On Windows the Win32 API will be queried for the `NumberOfCores from
+  # Win32_Processor`. This will return the total number "of cores for the
+  # current instance of the processor." On Unix-like operating systems either
+  # the `hwprefs` or `sysctl` utility will be called in a subshell and the
+  # returned value will be used. In the rare case where none of these methods
+  # work or an exception is raised the function will simply return 1.
+  #
+  # @return [Integer] number physical processor cores on the current system
+  #
+  # @see https://github.com/grosser/parallel/blob/4fc8b89d08c7091fe0419ca8fba1ec3ce5a8d185/lib/parallel.rb
+  #
+  # @see http://msdn.microsoft.com/en-us/library/aa394373(v=vs.85).aspx
+  # @see http://www.unix.com/man-page/osx/1/HWPREFS/
+  # @see http://linux.die.net/man/8/sysctl
+  def self.physical_processor_count: () -> Integer
+
+  # Number of processors seen by the OS and used for process scheduling. For
+  # performance reasons the calculated value will be memoized on the first
+  # call.
+  #
+  # When running under JRuby the Java runtime call
+  # `java.lang.Runtime.getRuntime.availableProcessors` will be used. According
+  # to the Java documentation this "value may change during a particular
+  # invocation of the virtual machine... [applications] should therefore
+  # occasionally poll this property." Subsequently the result will NOT be
+  # memoized under JRuby.
+  #
+  # Otherwise Ruby's Etc.nprocessors will be used.
+  #
+  # @return [Integer] number of processors seen by the OS or Java runtime
+  #
+  # @see http://docs.oracle.com/javase/6/docs/api/java/lang/Runtime.html#availableProcessors()
+  #
+  def self.processor_count: () -> Integer
+end

sig/steep/cli.rbs

@@ -10,8 +10,6 @@ module Steep
 
     attr_reader command: Symbol
 
-    include Parallel::ProcessorCount
-
     def initialize: (stdout: IO, stdin: IO, stderr: IO, argv: Array[String]) -> void
 
     def self.available_commands: () -> ::Array[Symbol]

sig/steep/drivers/utils/jobs_option.rbs

@@ -8,8 +8,6 @@ module Steep
 
         attr_reader jobs_count_modifier: Integer
 
-        include Parallel::ProcessorCount
-
         def initialize: (?jobs_count_modifier: Integer) -> void
 
         def default_jobs_count: () -> Integer

steep.gemspec

@@ -34,7 +34,7 @@ Gem::Specification.new do |spec|
   spec.add_runtime_dependency "listen", "~> 3.0"
   spec.add_runtime_dependency "language_server-protocol", ">= 3.15", "< 4.0"
   spec.add_runtime_dependency "rbs", ">= 2.8.0"
-  spec.add_runtime_dependency "parallel", ">= 1.0.0"
+  spec.add_runtime_dependency "concurrent-ruby", ">= 1.2.2"
   spec.add_runtime_dependency "terminal-table", ">= 2", "< 4"
   spec.add_runtime_dependency "securerandom", ">= 0.1"
   spec.add_runtime_dependency "json", ">= 2.1.0"