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# frozen_string_literal: true
# Copyright, 2018, by Samuel G. D. Williams. <http://www.codeotaku.com>
#
# 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.
require 'async/semaphore'
require 'async/barrier'
require 'async/rspec'
require_relative 'chainable_async_examples'
RSpec.describe Async::Semaphore do
include_context Async::RSpec::Reactor
context '#async' do
let(:repeats) {40}
let(:limit) {4}
it 'should process work in batches' do
semaphore = Async::Semaphore.new(limit)
current, maximum = 0, 0
result = repeats.times.map do |i|
semaphore.async do |task|
current += 1
maximum = [current, maximum].max
task.sleep(rand * 0.1)
current -= 1
i
end
end.collect(&:result)
# Verify that the maximum number of concurrent tasks was the specificed limit:
expect(maximum).to be == limit
# Verify that the results were in the correct order:
expect(result).to be == (0...repeats).to_a
end
it 'only allows one task at a time' do
semaphore = Async::Semaphore.new(1)
order = []
3.times.map do |i|
semaphore.async do |task|
order << i
task.sleep(0.1)
order << i
end
end.collect(&:result)
expect(order).to be == [0, 0, 1, 1, 2, 2]
end
it 'allows tasks to execute concurrently' do
semaphore = Async::Semaphore.new(3)
order = []
3.times.map do |i|
semaphore.async do |task|
order << i
task.sleep(0.1)
order << i
end
end.collect(&:result)
expect(order).to be == [0, 1, 2, 0, 1, 2]
end
end
context '#waiting' do
subject {Async::Semaphore.new(0)}
it 'handles exceptions thrown while waiting' do
expect do
reactor.with_timeout(0.1) do
subject.acquire do
end
end
end.to raise_error(Async::TimeoutError)
expect(subject.waiting).to be_empty
end
end
context '#count' do
it 'should count number of current acquisitions' do
expect(subject.count).to be == 0
subject.acquire do
expect(subject.count).to be == 1
end
end
end
context '#limit' do
it 'should have a default limit' do
expect(subject.limit).to be == 1
end
end
context '#empty?' do
it 'should be empty unless acquired' do
expect(subject).to be_empty
subject.acquire do
expect(subject).to_not be_empty
end
end
end
context '#blocking?' do
it 'will be blocking when acquired' do
expect(subject).to_not be_blocking
subject.acquire do
expect(subject).to be_blocking
end
end
end
context '#acquire/#release' do
it 'works when called without block' do
subject.acquire
expect(subject.count).to be == 1
subject.release
expect(subject.count).to be == 0
end
end
context 'with barrier' do
let(:capacity) {2}
let(:barrier) {Async::Barrier.new}
let(:repeats) {capacity * 2}
it 'should execute several tasks and wait using a barrier' do
repeats.times do
subject.async(parent: barrier) do |task|
task.sleep 0.1
end
end
expect(barrier.size).to be == repeats
barrier.wait
end
end
it_behaves_like 'chainable async'
end
|
