ruby/bootstraptest/test_ractor.rb

# Ractor.current returns a current ractor
assert_equal 'Ractor', %q{
  Ractor.current.class
}

# Ractor.new returns new Ractor
assert_equal 'Ractor', %q{
  Ractor.new{}.class
}

# Ractor.new must call with a block
assert_equal "must be called with a block", %q{
  begin
    Ractor.new
  rescue ArgumentError => e
    e.message
  end
}


# A return value of a Ractor block will be a message from the Ractor.
assert_equal 'ok', %q{
  # join
  r = Ractor.new do
    'ok'
  end
  r.take
}

# Passed arguments to Ractor.new will be a block parameter
# The values are passed with Ractor-communication pass.
assert_equal 'ok', %q{
  # ping-pong with arg
  r = Ractor.new 'ok' do |msg|
    msg
  end
  r.take
}

assert_equal 'ok', %q{
  # ping-pong with two args
  r =  Ractor.new 'ping', 'pong' do |msg, msg2|
    [msg, msg2]
  end
  'ok' if r.take == ['ping', 'pong']
}

# Ractor#send passes an object with copy to a Ractor
# and Ractor.recv in the Ractor block can receive the passed value.
assert_equal 'ok', %q{
  r = Ractor.new do
    msg = Ractor.recv
  end
  r.send 'ok'
  r.take
}

# Ractor.select(*ractors) receives a values from a ractors.
# It is similar to select(2) and Go's select syntax.
# The return value is [ch, received_value]
assert_equal 'ok', %q{
  # select 1
  r1 = Ractor.new{'r1'}
  r, obj = Ractor.select(r1)
  'ok' if r == r1 and obj == 'r1'
}

assert_equal '["r1", "r2"]', %q{
  # select 2
  r1 = Ractor.new{'r1'}
  r2 = Ractor.new{'r2'}
  rs = [r1, r2]
  as = []
  r, obj = Ractor.select(*rs)
  rs.delete(r)
  as << obj
  r, obj = Ractor.select(*rs)
  as << obj
  as.sort #=> ["r1", "r2"]
}

assert_equal 'true', %q{
  def test n
    rs = (1..n).map do |i|
      Ractor.new(i) do |i|
        "r#{i}"
      end
    end
    as = []
    all_rs = rs.dup

    n.times{
      r, obj = Ractor.select(*rs)
      as << [r, obj]
      rs.delete(r)
    }

    if as.map{|r, o| r.inspect}.sort == all_rs.map{|r| r.inspect}.sort &&
       as.map{|r, o| o}.sort == (1..n).map{|i| "r#{i}"}.sort
      'ok'
    else
      'ng'
    end
  end

  30.times.map{|i|
    test i
  }.all?('ok')
}

# Outgoing port of a ractor will be closed when the Ractor is terminated.
assert_equal 'ok', %q{
  r = Ractor.new do
    'finish'
  end

  r.take
  sleep 0.1 # wait for terminate

  begin
    o = r.take
  rescue Ractor::ClosedError
    'ok'
  else
    "ng: #{o}"
  end
}

assert_equal 'ok', %q{
  r = Ractor.new do
  end

  r.take # closed
  sleep 0.1 # wait for terminate

  begin
    r.send(1)
  rescue Ractor::ClosedError
    'ok'
  else
    'ng'
  end
}

# multiple Ractors can recv (wait) from one Ractor
assert_equal '[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]', %q{
  pipe = Ractor.new do
    loop do
      Ractor.yield Ractor.recv
    end
  end

  RN = 10
  rs = RN.times.map{|i|
    Ractor.new pipe, i do |pipe, i|
      msg = pipe.take
      msg # ping-pong
    end
  }
  RN.times{|i|
    pipe << i
  }
  RN.times.map{
    r, n = Ractor.select(*rs)
    rs.delete r
    n
  }.sort
}

# Ractor.select also support multiple take, recv and yiled
assert_equal '[true, true, true]', %q{
  RN = 10
  CR = Ractor.current

  rs = (1..RN).map{
    Ractor.new do
      CR.send 'send' + CR.take #=> 'sendyield'
      'take'
    end
  }
  recv = []
  take = []
  yiel = []
  until rs.empty?
    r, v = Ractor.select(CR, *rs, yield_value: 'yield')
    case r
    when :recv
      recv << v
    when :yield
      yiel << v
    else
      take << v
      rs.delete r
    end
  end
  [recv.all?('sendyield'), yiel.all?(nil), take.all?('take')]
}

# multiple Ractors can send to one Ractor
assert_equal '[0, 1, 2, 3, 4, 5, 6, 7, 8, 9]', %q{
  pipe = Ractor.new do
    loop do
      Ractor.yield Ractor.recv
    end
  end

  RN = 10
  RN.times.map{|i|
    Ractor.new pipe, i do |pipe, i|
      pipe << i
    end
  }
  RN.times.map{
    pipe.take
  }.sort
}

# an exception in a Ractor will be re-raised at Ractor#recv
assert_equal '[RuntimeError, "ok", true]', %q{
  r = Ractor.new do
    raise 'ok' # exception will be transferred receiver
  end
  begin
    r.take
  rescue Ractor::RemoteError => e
    [e.cause.class,   #=> RuntimeError
     e.cause.message, #=> 'ok'
     e.ractor == r]   #=> true
  end
}

# unshareable object are copied
assert_equal 'false', %q{
  obj = 'str'.dup
  r = Ractor.new obj do |msg|
    msg.object_id
  end
  
  obj.object_id == r.take
}

# To copy the object, now Marshal#dump is used
assert_equal 'no _dump_data is defined for class Thread', %q{
  obj = Thread.new{}
  begin
    r = Ractor.new obj do |msg|
      msg
    end
  rescue TypeError => e
    e.message #=> no _dump_data is defined for class Thread
  else
    'ng'
  end
}

# send sharable and unsharable objects
assert_equal "[[[1, true], [:sym, true], [:xyzzy, true], [\"frozen\", true], " \
             "[(3/1), true], [(3+4i), true], [/regexp/, true], [C, true]], " \
             "[[\"mutable str\", false], [[:array], false], [{:hash=>true}, false]]]", %q{
  r = Ractor.new do
    while v = Ractor.recv
      Ractor.yield v
    end
  end

  class C
  end

  sharable_objects = [1, :sym, 'xyzzy'.to_sym, 'frozen'.freeze, 1+2r, 3+4i, /regexp/, C]

  sr = sharable_objects.map{|o|
    r << o
    o2 = r.take
    [o, o.object_id == o2.object_id]
  }

  ur = unsharable_objects = ['mutable str'.dup, [:array], {hash: true}].map{|o|
    r << o
    o2 = r.take
    [o, o.object_id == o2.object_id]
  }
  [sr, ur].inspect
}

# move example2: String
# touching moved object causes an error
assert_equal 'hello world', %q{
  # move
  r = Ractor.new do
    obj = Ractor.recv
    obj << ' world'
  end

  str = 'hello'
  r.send str, move: true
  modified = r.take

  begin
    str << ' exception' # raise Ractor::MovedError
  rescue Ractor::MovedError
    modified #=> 'hello world'
  else
    raise 'unreachable'
  end
}

# move example2: Array
assert_equal '[0, 1]', %q{
  r = Ractor.new do
    ary = Ractor.recv
    ary << 1
  end

  a1 = [0]
  r.send a1, move: true
  a2 = r.take
  begin
    a1 << 2 # raise Ractor::MovedError
  rescue Ractor::MovedError
    a2.inspect
  end
}

# move with yield
assert_equal 'hello', %q{
  r = Ractor.new do
    Thread.current.report_on_exception = false
    obj = 'hello'
    Ractor.yield obj, move: true
    obj << 'world'
  end

  str = r.take
  begin
    r.take 
  rescue Ractor::RemoteError
    str #=> "hello"
  end
}

# Access to global-variables are prohibitted
assert_equal 'can not access global variables $gv from non-main Ractors', %q{
  $gv = 1
  r = Ractor.new do
    $gv
  end

  begin
    r.take
  rescue Ractor::RemoteError => e
    e.cause.message
  end
}

# Access to global-variables are prohibitted
assert_equal 'can not access global variables $gv from non-main Ractors', %q{
  r = Ractor.new do
    $gv = 1
  end

  begin
    r.take
  rescue Ractor::RemoteError => e
    e.cause.message
  end
}

# $stdin,out,err is Ractor local, but shared fds
assert_equal 'ok', %q{
  r = Ractor.new do
    [$stdin, $stdout, $stderr].map{|io|
      [io.object_id, io.fileno]
    }
  end

  [$stdin, $stdout, $stderr].zip(r.take){|io, (oid, fno)|
    raise "should not be different object" if io.object_id == oid
    raise "fd should be same" unless io.fileno == fno
  }
  'ok'
}

# selfs are different objects
assert_equal 'false', %q{
  r = Ractor.new do
    self.object_id
  end
  r.take == self.object_id #=> false
}

# self is a Ractor instance
assert_equal 'true', %q{
  r = Ractor.new do
    self.object_id
  end
  r.object_id == r.take #=> true
}

# given block Proc will be isolated, so can not access outer variables.
assert_equal 'ArgumentError', %q{
  begin
    a = true
    r = Ractor.new do
      a
    end
  rescue => e
    e.class
  end
}

# ivar in sharable-objects are not allowed to access from non-main Ractor
assert_equal 'can not access instance variables of classes/modules from non-main Ractors', %q{
  class C
    @iv = 'str'
  end

  r = Ractor.new do
    class C
      p @iv
    end
  end


  begin
    r.take
  rescue Ractor::RemoteError => e
    e.cause.message
  end
}

# ivar in sharable-objects are not allowed to access from non-main Ractor
assert_equal 'can not access instance variables of shareable objects from non-main Ractors', %q{
  shared = Ractor.new{}
  shared.instance_variable_set(:@iv, 'str')

  r = Ractor.new shared do |shared|
    p shared.instance_variable_get(:@iv)
  end

  begin
    r.take
  rescue Ractor::RemoteError => e
    e.cause.message
  end
}

# cvar in sharable-objects are not allowed to access from non-main Ractor
assert_equal 'can not access class variables from non-main Ractors', %q{
  class C
    @@cv = 'str'
  end

  r = Ractor.new do
    class C
      p @@cv
    end
  end

  begin
    r.take
  rescue Ractor::RemoteError => e
    e.cause.message
  end
}

# Getting non-sharable objects via constants by other Ractors is not allowed
assert_equal 'can not access non-sharable objects in constant C::CONST by non-main Ractor.', %q{
  class C
    CONST = 'str'
  end
  r = Ractor.new do
    C::CONST
  end
  begin
    r.take
  rescue Ractor::RemoteError => e
    e.cause.message
  end
}

# Setting non-sharable objects into constants by other Ractors is not allowed
assert_equal 'can not set constants with non-shareable objects by non-main Ractors', %q{
  class C
  end
  r = Ractor.new do
    C::CONST = 'str'
  end
  begin
    r.take
  rescue Ractor::RemoteError => e
    e.cause.message
  end
}

# Immutable Array and Hash are shareable, so it can be shared with constants
assert_equal '[1000, 3]', %q{
  A = Array.new(1000).freeze # [nil, ...]
  H = {a: 1, b: 2, c: 3}.freeze

  Ractor.new{ [A.size, H.size] }.take
}

# A Ractor can have a name
assert_equal 'test-name', %q{
  r = Ractor.new name: 'test-name' do
  end
  r.name
}

# If Ractor doesn't have a name, Ractor#name returns nil.
assert_equal 'nil', %q{
  r = Ractor.new do
  end
  r.name.inspect
}