Bowling Solo Challenge

Gemfile

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+source "https://rubygems.org"
+
+# gem "rails"
+
+gem "rspec", "~> 3.12"

Gemfile.lock

@@ -0,0 +1,26 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    diff-lcs (1.5.0)
+    rspec (3.12.0)
+      rspec-core (~> 3.12.0)
+      rspec-expectations (~> 3.12.0)
+      rspec-mocks (~> 3.12.0)
+    rspec-core (3.12.2)
+      rspec-support (~> 3.12.0)
+    rspec-expectations (3.12.3)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.12.0)
+    rspec-mocks (3.12.5)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.12.0)
+    rspec-support (3.12.0)
+
+PLATFORMS
+  arm64-darwin-22
+
+DEPENDENCIES
+  rspec (~> 3.12)
+
+BUNDLED WITH
+   2.4.12

lib/frame.rb

@@ -0,0 +1,15 @@
+class Frame
+  attr_reader :scores
+
+  def initialize(*scores)
+    @scores = scores
+  end
+
+  def strike?
+    @scores.first == 10
+  end
+
+  def spare?
+    !strike? && @scores.sum == 10
+  end
+end

lib/scorecard.rb

@@ -0,0 +1,46 @@
+require 'frame'
+
+class Scorecard
+  def initialize
+    @frames = []
+  end
+
+  def add_frame(*scores)
+    @frames << Frame.new(*scores)
+  end
+
+  def calculate_score
+    @frames[0..9].reduce(0) { |sum, frame| sum + get_frame_score(frame) }
+  end
+
+  def perfect_game?
+    calculate_score == 300
+  end
+
+  def gutter_game?
+    calculate_score == 0
+  end
+
+  private
+
+  def get_frame_score(frame)
+    i = @frames.index(frame)
+    score = @frames[i].scores.sum
+    return score + get_next_roll(i) if frame.spare?
+    return score + get_next_two_rolls(i) if frame.strike?
+    return score
+  end
+
+  def get_next_roll(current_frame_index)
+    @frames[current_frame_index + 1].scores.first
+  end
+
+  def get_next_two_rolls(current_frame_index)
+    score = get_next_roll(current_frame_index)
+    if @frames[current_frame_index + 1].scores.length == 1
+      return score + @frames[current_frame_index + 2].scores.first
+    else
+      return score + @frames[current_frame_index + 1].scores.last
+    end
+  end
+end

spec/frame_spec.rb

@@ -0,0 +1,68 @@
+require 'frame'
+
+RSpec.describe Frame do
+  context 'when initialized with two zeros' do
+    it 'has those scores' do
+      frame = Frame.new(0, 0)
+      expect(frame.scores).to eq [0, 0]
+    end
+
+    it 'is not a strike' do
+      frame = Frame.new(0, 0)
+      expect(frame.strike?).to eq false
+    end
+
+    it 'is not a spare' do
+      frame = Frame.new(0, 0)
+      expect(frame.spare?).to eq false
+    end
+  end
+
+  context 'when initialised with two numbers that add up to 9' do
+    it 'has those scores' do
+      frame = Frame.new(4, 5)
+      expect(frame.scores).to eq [4, 5]
+    end
+
+    it 'is not a strike' do
+      frame = Frame.new(4, 5)
+      expect(frame.strike?).to eq false
+    end
+
+    it 'is not a spare' do
+      frame = Frame.new(4, 5)
+      expect(frame.spare?).to eq false
+    end
+  end
+
+  context 'when initialised with two numbers that add up to 10' do
+    it 'is a spare' do
+      frame = Frame.new(2, 8)
+      expect(frame.spare?).to eq true
+    end
+  end
+
+  context 'when initialised with another two numbers that add up to 10' do
+    it 'is also a spare' do
+      frame = Frame.new(9, 1)
+      expect(frame.spare?).to eq true
+    end
+  end
+
+  context 'when initialised with 10' do
+    it 'has that score' do
+      frame = Frame.new(10)
+      expect(frame.scores).to eq [10]
+    end
+
+    it 'is a strike' do
+      frame = Frame.new(10)
+      expect(frame.strike?).to eq true
+    end
+
+    it 'is not a spare' do
+      frame = Frame.new(10)
+      expect(frame.spare?).to eq false
+    end
+  end
+end

spec/integration/scorecard_frame_spec.rb

@@ -0,0 +1,220 @@
+require 'frame'
+require 'scorecard'
+
+describe 'integration' do
+  context 'when there are no spares or strikes' do
+    it 'calculates the score' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+
+      expect(scorecard.calculate_score).to eq 30
+    end
+  end
+
+  context 'when there are spares' do
+    it 'calculates the score' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 9)
+      scorecard.add_frame(3, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(5, 5)
+      scorecard.add_frame(9, 0)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+
+      expect(scorecard.calculate_score).to eq 64
+    end
+  end
+
+  context 'when there are strikes' do
+    it 'calculates the score' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(10)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(10)
+      scorecard.add_frame(3, 2)
+
+      expect(scorecard.calculate_score).to eq 54
+    end
+  end
+
+  context 'when there are multiple strikes in a row' do
+    it 'calculates the score' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(3, 2)
+      scorecard.add_frame(3, 2)
+
+      expect(scorecard.calculate_score).to eq 89
+    end
+  end
+
+  context 'when 10th frame is a spare' do
+    it 'adds the first endgame bonus score to the total score' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(3, 2)
+      scorecard.add_frame(3, 7)
+      # bonus
+      scorecard.add_frame(3)
+
+      expect(scorecard.calculate_score).to eq 97
+    end
+  end
+
+  context 'when 10th frame is a strike' do
+    it 'adds two endgame bonus scores to the total score' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(3, 2)
+      scorecard.add_frame(10)
+      # bonus
+      scorecard.add_frame(3, 10)
+
+      expect(scorecard.calculate_score).to eq 107
+    end
+  end
+
+  context 'the game ends with two strikes in a row' do
+    it 'the first endgame bonus is used as a bonus for the ninth frame' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(1, 2)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      # bonus
+      scorecard.add_frame(3, 10)
+
+      expect(scorecard.calculate_score).to eq 125
+    end
+  end
+
+  context 'the game is all strikes' do
+    it 'is a perfect game with score of 300' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      # bonus
+      scorecard.add_frame(10, 10)
+
+      expect(scorecard.calculate_score).to eq 300
+      expect(scorecard.perfect_game?).to eq true
+      expect(scorecard.gutter_game?).to eq false
+    end
+  end
+
+  context 'the player never hits a pin' do
+    it 'is a gutter game with a score of 0' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+
+      expect(scorecard.calculate_score).to eq 0
+      expect(scorecard.perfect_game?).to eq false
+      expect(scorecard.gutter_game?).to eq true
+    end
+  end
+
+  context 'the player hits one pin' do
+    it 'is not a gutter game' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 1)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+      scorecard.add_frame(0, 0)
+
+      expect(scorecard.calculate_score).to eq 1
+      expect(scorecard.perfect_game?).to eq false
+      expect(scorecard.gutter_game?).to eq false
+    end
+  end
+
+  context 'the player doesn\'t get all strikes' do
+    it 'is not a perfect game' do
+      scorecard = Scorecard.new
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(9, 1)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      scorecard.add_frame(10)
+      # bonus
+      scorecard.add_frame(10, 10)
+
+      expect(scorecard.calculate_score).to eq 279
+      expect(scorecard.perfect_game?).to eq false
+      expect(scorecard.gutter_game?).to eq false
+    end
+  end
+end

spec/scorecard_spec.rb

@@ -0,0 +1,4 @@
+require 'scorecard'
+
+RSpec.describe Scorecard do
+end