catstodon/spec/lib/connection_pool/shared_timed_stack_spec.rb

# frozen_string_literal: true

require 'rails_helper'

RSpec.describe ConnectionPool::SharedTimedStack do
  subject { described_class.new(5) { |site| mini_connection_class.new(site) } }

  let(:mini_connection_class) do
    Class.new do
      attr_reader :site

      def initialize(site)
        @site = site
      end
    end
  end

  describe '#push' do
    it 'keeps the connection in the stack' do
      subject.push(mini_connection_class.new('foo'))
      expect(subject.size).to eq 1
    end
  end

  describe '#pop' do
    it 'returns a connection' do
      expect(subject.pop('foo')).to be_a mini_connection_class
    end

    it 'returns the same connection that was pushed in' do
      connection = mini_connection_class.new('foo')
      subject.push(connection)
      expect(subject.pop('foo')).to be connection
    end

    it 'does not create more than maximum amount of connections' do
      expect { 6.times { subject.pop('foo', 0) } }.to raise_error Timeout::Error
    end

    it 'repurposes a connection for a different site when maximum amount is reached' do
      5.times { subject.push(mini_connection_class.new('foo')) }
      expect(subject.pop('bar')).to be_a mini_connection_class
    end
  end

  describe '#empty?' do
    it 'returns true when no connections on the stack' do
      expect(subject.empty?).to be true
    end

    it 'returns false when there are connections on the stack' do
      subject.push(mini_connection_class.new('foo'))
      expect(subject.empty?).to be false
    end
  end

  describe '#size' do
    it 'returns the number of connections on the stack' do
      2.times { subject.push(mini_connection_class.new('foo')) }
      expect(subject.size).to eq 2
    end
  end
end