From ca52d62a4134818f86e871bbd5f2c55ae4045e46 Mon Sep 17 00:00:00 2001
From: Ryan Bigg <me@ryanbigg.com>
Date: Fri, 2 Feb 2024 09:32:40 +1100
Subject: [PATCH] Add Teferi, Master of Time

Fixes #85
---
 lib/magic/ability.rb                          | 29 +++++++++++
 lib/magic/actions/activate_loyalty_ability.rb | 21 +++-----
 lib/magic/activated_ability.rb                | 28 +---------
 lib/magic/card_list.rb                        |  4 ++
 lib/magic/cards/basri_ket.rb                  |  6 +--
 lib/magic/cards/planeswalker.rb               |  4 ++
 lib/magic/cards/shared/events.rb              |  2 +
 lib/magic/cards/teferi_master_of_time.rb      | 47 +++++++++++++++++
 lib/magic/cards/ugin_the_spirit_dragon.rb     |  6 +--
 lib/magic/choice/discard.rb                   |  2 +-
 lib/magic/effects/phase_out.rb                | 10 ++++
 lib/magic/game.rb                             | 28 +++++++---
 lib/magic/game/turn.rb                        |  1 +
 lib/magic/loyalty_ability.rb                  |  8 +--
 lib/magic/permanent.rb                        | 13 +++++
 lib/magic/permanents/planeswalker.rb          |  2 +-
 lib/magic/zones/battlefield.rb                |  2 +-
 spec/cards/academy_elite_spec.rb              |  2 +-
 spec/cards/capture_sphere_spec.rb             |  2 -
 spec/cards/frost_breath_spec.rb               |  2 -
 spec/cards/rain_of_revelation_spec.rb         |  4 +-
 spec/cards/rousing_read_spec.rb               |  3 +-
 spec/cards/sanctum_of_calm_waters_spec.rb     |  2 +-
 spec/cards/teferi_master_of_time_spec.rb      | 51 +++++++++++++++++++
 spec/game/integration/turns_spec.rb           |  2 +-
 spec/game/integration/untap_spec.rb           | 17 +++++++
 .../integration/until_end_of_turn_spec.rb     |  4 --
 spec/game_spec.rb                             | 33 ++++++++++++
 28 files changed, 256 insertions(+), 79 deletions(-)
 create mode 100644 lib/magic/ability.rb
 create mode 100644 lib/magic/cards/teferi_master_of_time.rb
 create mode 100644 lib/magic/effects/phase_out.rb
 create mode 100644 spec/cards/teferi_master_of_time_spec.rb
 create mode 100644 spec/game/integration/untap_spec.rb
 create mode 100644 spec/game_spec.rb

diff --git a/lib/magic/ability.rb b/lib/magic/ability.rb
new file mode 100644
index 00000000..7b73944b
--- /dev/null
+++ b/lib/magic/ability.rb
@@ -0,0 +1,29 @@
+module Magic
+  class Ability
+    attr_reader :source
+
+    def initialize(source:)
+      @source = source
+    end
+
+    def game
+      source.game
+    end
+
+    def battlefield
+      game.battlefield
+    end
+
+    def controller
+      source.controller
+    end
+
+    def trigger_effect(effect, **args)
+      source.trigger_effect(effect, source: self, **args)
+    end
+
+    def add_choice(choice, **args)
+      source.add_choice(choice, **args)
+    end
+  end
+end
diff --git a/lib/magic/actions/activate_loyalty_ability.rb b/lib/magic/actions/activate_loyalty_ability.rb
index a0f80214..3d930108 100644
--- a/lib/magic/actions/activate_loyalty_ability.rb
+++ b/lib/magic/actions/activate_loyalty_ability.rb
@@ -4,7 +4,7 @@ class ActivateLoyaltyAbility < Action
       attr_reader :ability, :planeswalker, :targets, :x_value
 
       def initialize(ability:, **args)
-        @planeswalker = ability.planeswalker
+        @planeswalker = ability.source
         @ability = ability
         @targets = []
         super(**args)
@@ -44,19 +44,12 @@ def perform
       end
 
       def resolve!
-        if targets.any?
-          if ability.single_target?
-            ability.resolve!(target: targets.first)
-          else
-            ability.resolve!(targets: targets)
-          end
-        else
-          if x_value
-            ability.resolve!(value_for_x: x_value)
-          else
-            ability.resolve!
-          end
-        end
+        resolver = ability.method(:resolve!)
+        args = {}
+        args[:target] = targets.first if resolver.parameters.include?([:keyreq, :target])
+        args[:targets] = targets if resolver.parameters.include?([:keyreq, :targets])
+        args[:value_for_x] = x_value if x_value && resolver.parameters.include?([:keyreq, :value_for_x])
+        ability.resolve!(**args)
       end
     end
   end
diff --git a/lib/magic/activated_ability.rb b/lib/magic/activated_ability.rb
index 3bfbed04..074f0f08 100644
--- a/lib/magic/activated_ability.rb
+++ b/lib/magic/activated_ability.rb
@@ -1,11 +1,5 @@
 module Magic
-  class ActivatedAbility
-    attr_reader :source
-
-    def initialize(source:)
-      @source = source
-    end
-
+  class ActivatedAbility < Ability
     def valid_targets?(*targets)
       targets.all? { target_choices.include?(_1) }
     end
@@ -13,25 +7,5 @@ def valid_targets?(*targets)
     def costs
       @costs || self.class::COSTS.dup
     end
-
-    def game
-      source.game
-    end
-
-    def battlefield
-      game.battlefield
-    end
-
-    def controller
-      source.controller
-    end
-
-    def trigger_effect(effect, **args)
-      source.trigger_effect(effect, source: self, **args)
-    end
-
-    def add_choice(choice, **args)
-      source.add_choice(choice, **args)
-    end
   end
 end
diff --git a/lib/magic/card_list.rb b/lib/magic/card_list.rb
index 26f4fbd6..ae4f8ca8 100644
--- a/lib/magic/card_list.rb
+++ b/lib/magic/card_list.rb
@@ -1,5 +1,9 @@
 module Magic
   class CardList < SimpleDelegator
+    def phased_out
+      select(&:phased_out?)
+    end
+
     def controlled_by(player)
       select { |card| card.controller == player }
     end
diff --git a/lib/magic/cards/basri_ket.rb b/lib/magic/cards/basri_ket.rb
index 9c142c50..271a0ddb 100644
--- a/lib/magic/cards/basri_ket.rb
+++ b/lib/magic/cards/basri_ket.rb
@@ -45,14 +45,14 @@ class LoyaltyAbility2 < Magic::LoyaltyAbility
         def loyalty_change = -2
 
         def resolve!
-          planeswalker.delayed_response(
+          source.delayed_response(
             turn: game.current_turn,
             event_type: Events::PreliminaryAttackersDeclared,
             response: -> {
               attackers = game.current_turn.attacks.count
 
               attackers.times do
-                token = planeswalker.controller.create_token(token_class: SoldierToken, enters_tapped: true)
+                token = source.controller.create_token(token_class: SoldierToken, enters_tapped: true)
 
                 game.current_turn.declare_attacker(token)
               end
@@ -65,7 +65,7 @@ class LoyaltyAbility3 < Magic::LoyaltyAbility
         def loyalty_change = -6
 
         def resolve!
-          game.add_emblem(Emblem.new(owner: planeswalker.controller))
+          game.add_emblem(Emblem.new(owner: source.controller))
         end
       end
 
diff --git a/lib/magic/cards/planeswalker.rb b/lib/magic/cards/planeswalker.rb
index 40073e74..02df54ca 100644
--- a/lib/magic/cards/planeswalker.rb
+++ b/lib/magic/cards/planeswalker.rb
@@ -1,6 +1,10 @@
 module Magic
   module Cards
     class Planeswalker < Card
+      def self.loyalty(loyalty)
+        const_set(:BASE_LOYALTY, loyalty)
+      end
+
       def loyalty
         self.class::BASE_LOYALTY
       end
diff --git a/lib/magic/cards/shared/events.rb b/lib/magic/cards/shared/events.rb
index 393167ec..716967da 100644
--- a/lib/magic/cards/shared/events.rb
+++ b/lib/magic/cards/shared/events.rb
@@ -31,6 +31,8 @@ def trigger_effect(effect, source: self, **args)
             game.add_effect(Effects::LoseLife.new(source: source, **args))
           when :modify_power_toughness
             game.add_effect(Effects::ApplyPowerToughnessModification.new(source: source, **args))
+          when :phase_out
+            game.add_effect(Effects::PhaseOut.new(source: source, **args))
           when :return_to_owners_hand
             game.add_effect(Effects::ReturnToOwnersHand.new(source: source, **args))
           when :tap
diff --git a/lib/magic/cards/teferi_master_of_time.rb b/lib/magic/cards/teferi_master_of_time.rb
new file mode 100644
index 00000000..810b8326
--- /dev/null
+++ b/lib/magic/cards/teferi_master_of_time.rb
@@ -0,0 +1,47 @@
+module Magic
+  module Cards
+    class TeferiMasterOfTime < Planeswalker
+      NAME = "Teferi, Master of Time"
+      TYPE_LINE = "Legendary Planeswalker -- Teferi"
+      cost generic: 2, blue: 2
+      loyalty 3
+
+      class LoyaltyAbility1 < LoyaltyAbility
+        def loyalty_change
+          1
+        end
+
+        def resolve!
+          trigger_effect(:draw_cards)
+          add_choice(:discard)
+        end
+      end
+
+      class LoyaltyAbility2 < LoyaltyAbility
+        def loyalty_change
+          -3
+        end
+
+        def target_choices
+          battlefield.creatures.not_controlled_by(controller)
+        end
+
+        def resolve!(target:)
+          trigger_effect(:phase_out, target: target)
+        end
+      end
+
+      class LoyaltyAbility3 < LoyaltyAbility
+        def loyalty_change
+          -10
+        end
+
+        def resolve!
+          2.times { game.take_additional_turn }
+        end
+      end
+
+      def loyalty_abilities = [LoyaltyAbility1, LoyaltyAbility2, LoyaltyAbility3]
+    end
+  end
+end
diff --git a/lib/magic/cards/ugin_the_spirit_dragon.rb b/lib/magic/cards/ugin_the_spirit_dragon.rb
index 7796f1ba..47b695bc 100644
--- a/lib/magic/cards/ugin_the_spirit_dragon.rb
+++ b/lib/magic/cards/ugin_the_spirit_dragon.rb
@@ -11,7 +11,7 @@ def target_choices = battlefield.cards + game.players
         def single_target? = true
 
         def resolve!(target:)
-          target.take_damage(source: planeswalker, damage: 3)
+          target.take_damage(source: source, damage: 3)
         end
       end
 
@@ -32,11 +32,11 @@ class LoyaltyAbility3 < Magic::LoyaltyAbility
         def loyalty_change = -7
 
         def resolve!
-          controller = planeswalker.controller
+          controller = source.controller
           controller.gain_life(7)
           7.times { controller.draw! }
 
-          game.choices.add(UginTheSpiritDragon::Choice.new(source: planeswalker))
+          game.choices.add(UginTheSpiritDragon::Choice.new(source: source))
         end
       end
 
diff --git a/lib/magic/choice/discard.rb b/lib/magic/choice/discard.rb
index 2480f349..80556f64 100644
--- a/lib/magic/choice/discard.rb
+++ b/lib/magic/choice/discard.rb
@@ -8,7 +8,7 @@ def initialize(player:)
         @cards = player.hand
       end
 
-      def choose(card)
+      def resolve!(card:)
         card.move_to_graveyard!
       end
     end
diff --git a/lib/magic/effects/phase_out.rb b/lib/magic/effects/phase_out.rb
new file mode 100644
index 00000000..7c696340
--- /dev/null
+++ b/lib/magic/effects/phase_out.rb
@@ -0,0 +1,10 @@
+module Magic
+  module Effects
+    class PhaseOut < TargetedEffect
+
+      def resolve!
+        target.phase_out!
+      end
+    end
+  end
+end
diff --git a/lib/magic/game.rb b/lib/magic/game.rb
index 25a61b4c..fc21c40f 100644
--- a/lib/magic/game.rb
+++ b/lib/magic/game.rb
@@ -2,7 +2,7 @@ module Magic
   class Game
     extend Forwardable
 
-    attr_reader :logger, :battlefield, :exile, :stack, :players, :emblems, :current_turn
+    attr_reader :logger, :battlefield, :exile, :turns, :stack, :players, :emblems, :current_turn
 
     def_delegators :@stack, :choices, :add_choice, :skip_choice!, :resolve_choice!, :effects, :add_effect
 
@@ -33,7 +33,7 @@ def initialize(
       @player_count = 0
       @players = players
       @emblems = []
-      @turn_number = 0
+      @turns = []
     end
 
     def add_players(*players)
@@ -51,7 +51,7 @@ def add_emblem(emblem)
     end
 
     def start!
-      @current_turn = Turn.new(number: 1, game: self, active_player: players.first)
+      @current_turn = add_turn(number: 1, active_player: players.first)
       players.each do |player|
         7.times { player.draw! }
       end
@@ -61,12 +61,26 @@ def notify!(*events)
       current_turn.notify!(*events)
     end
 
+    def take_additional_turn(player: current_turn.active_player)
+      add_turn(number: @turns.size + 1, active_player: player)
+    end
+
+    def add_turn(number: @turns.size + 1, active_player: player)
+      turn = Turn.new(number: number, game: self, active_player: active_player)
+      @turns << turn
+      turn
+    end
+
     def next_turn
-      @turn_number += 1
-      logger.debug "Starting Turn #{@turn_number} - Active Player: #{@players.first}"
-      @current_turn = Turn.new(number: @turn_number, game: self, active_player: @players.first)
+      next_turn = turns.find { |turn| turn.number > current_turn.number }
+      if next_turn
+        @current_turn = next_turn
+        return next_turn
+      end
+
       next_active_player
-      @current_turn
+      logger.debug "Starting Turn #{@turn_number} - Active Player: #{@players.first}"
+      @current_turn = add_turn(number: current_turn.number + 1, active_player: @players.first)
     end
 
     def next_active_player
diff --git a/lib/magic/game/turn.rb b/lib/magic/game/turn.rb
index 55d96bbe..c348d580 100644
--- a/lib/magic/game/turn.rb
+++ b/lib/magic/game/turn.rb
@@ -18,6 +18,7 @@ class Turn
         end
 
         after_transition to: :untap do |turn|
+          turn.battlefield.phased_out.permanents.controlled_by(turn.active_player).each(&:phase_in!)
           turn.battlefield.permanents.controlled_by(turn.active_player).each(&:untap_during_untap_step)
         end
 
diff --git a/lib/magic/loyalty_ability.rb b/lib/magic/loyalty_ability.rb
index 9246a020..a767d33d 100644
--- a/lib/magic/loyalty_ability.rb
+++ b/lib/magic/loyalty_ability.rb
@@ -1,10 +1,4 @@
 module Magic
-  class LoyaltyAbility
-    attr_reader :planeswalker, :game
-
-    def initialize(planeswalker:)
-      @planeswalker = planeswalker
-      @game = planeswalker.game
-    end
+  class LoyaltyAbility < Ability
   end
 end
diff --git a/lib/magic/permanent.rb b/lib/magic/permanent.rb
index 391d9aac..8d81cab8 100644
--- a/lib/magic/permanent.rb
+++ b/lib/magic/permanent.rb
@@ -55,6 +55,7 @@ def initialize(game:, owner:, card:, token: false, cast: true, kicked: false, ti
       @damage = 0
       @protections = Protections.new(card.protections.dup)
       @exiled_cards = Magic::CardList.new([])
+      @phased_out = false
       @timestamp = timestamp
     end
 
@@ -319,6 +320,18 @@ def add_choice(choice, **args)
       card.add_choice(choice, **args)
     end
 
+    def phased_out?
+      @phased_out
+    end
+
+    def phase_out!
+      @phased_out = true
+    end
+
+    def phase_in!
+      @phased_out = false
+    end
+
     private
 
     def remove_until_eot_keyword_grants!
diff --git a/lib/magic/permanents/planeswalker.rb b/lib/magic/permanents/planeswalker.rb
index 9c2ddc3d..9846b781 100644
--- a/lib/magic/permanents/planeswalker.rb
+++ b/lib/magic/permanents/planeswalker.rb
@@ -19,7 +19,7 @@ def take_damage(source:, damage:)
       end
 
       def loyalty_abilities
-        card.loyalty_abilities.map { |ability| ability.new(planeswalker: self) }
+        card.loyalty_abilities.map { |ability| ability.new(source: self) }
       end
     end
   end
diff --git a/lib/magic/zones/battlefield.rb b/lib/magic/zones/battlefield.rb
index d22035c7..5045c549 100644
--- a/lib/magic/zones/battlefield.rb
+++ b/lib/magic/zones/battlefield.rb
@@ -3,7 +3,7 @@ module Zones
     class Battlefield < Zone
       extend Forwardable
 
-      def_delegators :permanents, :creatures, :planeswalkers, :not_controlled_by, :controlled_by
+      def_delegators :permanents, :creatures, :planeswalkers, :not_controlled_by, :controlled_by, :phased_out
 
       def initialize(**args)
         super(**args)
diff --git a/spec/cards/academy_elite_spec.rb b/spec/cards/academy_elite_spec.rb
index 000c5258..74f3f00c 100644
--- a/spec/cards/academy_elite_spec.rb
+++ b/spec/cards/academy_elite_spec.rb
@@ -73,7 +73,7 @@
 
       choice = game.choices.last
       expect(choice).to be_a(Magic::Choice::Discard)
-      choice.choose(p1.hand.cards.first)
+      game.resolve_choice!(card: p1.hand.cards.first)
       expect(p1.graveyard.cards.count).to eq(1)
     end
   end
diff --git a/spec/cards/capture_sphere_spec.rb b/spec/cards/capture_sphere_spec.rb
index 8e70ffae..084a49d7 100644
--- a/spec/cards/capture_sphere_spec.rb
+++ b/spec/cards/capture_sphere_spec.rb
@@ -16,8 +16,6 @@
     # Enchanted creature doesn't untap during its controller's untap step.
 
     it "taps enchanted creature, equips aura" do
-      game.next_turn
-
       expect(game.current_turn.active_player).to eq(p1)
       p1.add_mana(white: 4)
       action = cast_action(player: p1, card: subject)
diff --git a/spec/cards/frost_breath_spec.rb b/spec/cards/frost_breath_spec.rb
index c01a1089..9242912a 100644
--- a/spec/cards/frost_breath_spec.rb
+++ b/spec/cards/frost_breath_spec.rb
@@ -9,8 +9,6 @@
 
   context "resolution" do
     it "taps two target creatures" do
-      game.next_turn
-
       p1.add_mana(blue: 3)
       action = cast_action(card: subject, player: p1).targeting(wood_elves, loxodon_wayfarer)
       action.pay_mana(blue: 1, generic: { blue: 2 })
diff --git a/spec/cards/rain_of_revelation_spec.rb b/spec/cards/rain_of_revelation_spec.rb
index 4e737e61..2ccd6548 100644
--- a/spec/cards/rain_of_revelation_spec.rb
+++ b/spec/cards/rain_of_revelation_spec.rb
@@ -12,8 +12,8 @@
 
       choice = game.choices.last
       expect(choice).to be_a(Magic::Choice::Discard)
-      card = choice.cards.first
-      choice.choose(card)
+      card = p1.hand.first
+      game.resolve_choice!(card: card)
 
       expect(card.zone).to be_graveyard
     end
diff --git a/spec/cards/rousing_read_spec.rb b/spec/cards/rousing_read_spec.rb
index e4176c21..4ef5c791 100644
--- a/spec/cards/rousing_read_spec.rb
+++ b/spec/cards/rousing_read_spec.rb
@@ -18,8 +18,7 @@
     game.tick!
 
     choice = game.choices.last
-    expect(choice).to be_a(Magic::Choice::Discard)
-    choice.choose(choice.cards.first)
+    game.resolve_choice!(card: choice.cards.first)
 
     expect(wood_elves.power).to eq(2)
     expect(wood_elves.toughness).to eq(2)
diff --git a/spec/cards/sanctum_of_calm_waters_spec.rb b/spec/cards/sanctum_of_calm_waters_spec.rb
index 20f84f2d..5f4599b4 100644
--- a/spec/cards/sanctum_of_calm_waters_spec.rb
+++ b/spec/cards/sanctum_of_calm_waters_spec.rb
@@ -18,7 +18,7 @@
 
       choice = game.choices.first
       expect(choice).to be_a(Magic::Choice::Discard)
-      choice.choose(p1.hand.cards.first)
+      game.resolve_choice!(card: p1.hand.cards.first)
     end
   end
 end
diff --git a/spec/cards/teferi_master_of_time_spec.rb b/spec/cards/teferi_master_of_time_spec.rb
new file mode 100644
index 00000000..24b392af
--- /dev/null
+++ b/spec/cards/teferi_master_of_time_spec.rb
@@ -0,0 +1,51 @@
+require 'spec_helper'
+
+RSpec.describe Magic::Cards::TeferiMasterOfTime do
+  include_context "two player game"
+
+  subject(:planeswalker) { ResolvePermanent("Teferi, Master Of Time") }
+
+  context "+1 ability" do
+    let(:ability) { planeswalker.loyalty_abilities.first }
+
+    it "draws, then discards a card" do
+      expect(p1).to receive(:draw!)
+      p1.activate_loyalty_ability(ability: ability)
+      game.tick!
+      expect(planeswalker.loyalty).to eq(4)
+
+      choice = game.choices.last
+      expect(choice).to be_a(Magic::Choice::Discard)
+      game.resolve_choice!(card: p1.hand.first)
+    end
+  end
+
+  context "-3 ability" do
+    let(:ability) { planeswalker.loyalty_abilities[1] }
+    let!(:wood_elves) { ResolvePermanent("Wood Elves", owner: p2) }
+
+    it "target creature you don't control phases out" do
+      p1.activate_loyalty_ability(ability: ability) do
+        _1.targeting(wood_elves)
+      end
+
+      game.tick!
+
+      expect(wood_elves).to be_phased_out
+    end
+  end
+
+  context "-10 ability" do
+    let(:ability) { planeswalker.loyalty_abilities[2] }
+
+    it "take two additional turns" do
+      p1.activate_loyalty_ability(ability: ability)
+
+      game.tick!
+
+      expect(game.turns.count).to eq(3)
+      # Turn 1 (current turn), Turn 2, and Turn 3
+      expect(game.turns.map(&:active_player)).to eq([p1, p1, p1])
+    end
+  end
+end
diff --git a/spec/game/integration/turns_spec.rb b/spec/game/integration/turns_spec.rb
index b11374a7..fe0e8ac9 100644
--- a/spec/game/integration/turns_spec.rb
+++ b/spec/game/integration/turns_spec.rb
@@ -20,7 +20,7 @@
     expect(p1.hand.count).to eq(7)
     expect(p2.hand.count).to eq(7)
 
-    turn_1 = game.next_turn
+    turn_1 = game.current_turn
 
     turn_1.untap!
     turn_1.upkeep!
diff --git a/spec/game/integration/untap_spec.rb b/spec/game/integration/untap_spec.rb
new file mode 100644
index 00000000..1de83642
--- /dev/null
+++ b/spec/game/integration/untap_spec.rb
@@ -0,0 +1,17 @@
+require 'spec_helper'
+
+RSpec.describe Magic::Game, "untap step" do
+  include_context "two player game"
+
+  let!(:dranas_emissary) { ResolvePermanent("Drana's Emissary", owner: p1) }
+
+  before do
+    dranas_emissary.phase_out!
+  end
+
+  it "phases back in" do
+    expect(dranas_emissary).to be_phased_out
+    current_turn.untap!
+    expect(dranas_emissary).not_to be_phased_out
+  end
+end
diff --git a/spec/game/integration/until_end_of_turn_spec.rb b/spec/game/integration/until_end_of_turn_spec.rb
index 10905c5a..dd65632c 100644
--- a/spec/game/integration/until_end_of_turn_spec.rb
+++ b/spec/game/integration/until_end_of_turn_spec.rb
@@ -5,10 +5,6 @@
 
   let!(:dranas_emissary) { ResolvePermanent("Drana's Emissary", owner: p1) }
 
-  before do
-    game.battlefield.add(dranas_emissary)
-  end
-
   def go_to_cleanup
     current_turn.untap!
     current_turn.upkeep!
diff --git a/spec/game_spec.rb b/spec/game_spec.rb
new file mode 100644
index 00000000..2a37079d
--- /dev/null
+++ b/spec/game_spec.rb
@@ -0,0 +1,33 @@
+require "spec_helper"
+
+RSpec.describe Magic::Game do
+  include_context "two player game"
+
+  context "take additional turn" do
+    it "player 1 has turns 1 and 2" do
+      game.take_additional_turn
+      expect(game.turns.size).to eq(2)
+      expect(game.turns.map(&:number)).to eq([1, 2])
+
+      expect(game.current_turn.number).to eq(1)
+      expect(game.current_turn.active_player).to eq(p1)
+
+      game.next_turn
+
+      expect(game.current_turn.number).to eq(2)
+      expect(game.current_turn.active_player).to eq(p1)
+    end
+  end
+
+  context "next_turn" do
+    it "player 1 has turns 1 and 2" do
+      expect(game.current_turn.number).to eq(1)
+      expect(game.current_turn.active_player).to eq(p1)
+
+      game.next_turn
+
+      expect(game.current_turn.number).to eq(2)
+      expect(game.current_turn.active_player).to eq(p2)
+    end
+  end
+end