Merge branch 'feature/ruby-canavas'

3 files changed, 14 insertions, 8 deletions

diff --git a/CLI/ruby/bin/game-of-life b/CLI/ruby/bin/game-of-life
index 16dc0fa..08dbeca 100755
--- a/CLI/ruby/bin/game-of-life
+++ b/CLI/ruby/bin/game-of-life
@@ -8,7 +8,7 @@ class CLI < Thor
   map %w[-v --version] => :version
   desc "--version, -v", "Prints the Game of Life version information"
   def version
-    puts "Game of Life version #{GameOfLife::VERSION}"
+    print "Game of Life version #{GameOfLife::VERSION}"
   end
 
   default_task :start
@@ -50,8 +50,10 @@ end
 begin
   CLI.start(ARGV)
 rescue SystemExit, Interrupt
-  "Do nothing when user exits with Interrupt (CMD/Ctrl + C)"
+  # Print Seed/File used in previous run when  user exits with Interrupt (CMD/Ctrl + C)
+  print "\e[?1049l"
+  print "#{GameOfLife::BANNER}\n\e[0m"
 rescue NotImplementedError, GameOfLife::Error => e
-  puts e.message
+  print e.message
   exit(-1)
 end
diff --git a/CLI/ruby/lib/game_of_life.rb b/CLI/ruby/lib/game_of_life.rb
index 2ff548c..b1a95f1 100644
--- a/CLI/ruby/lib/game_of_life.rb
+++ b/CLI/ruby/lib/game_of_life.rb
@@ -106,9 +106,13 @@ module GameOfLife
     # and rendering of the current universe/banner info
     # based on the delay/cell configured by the user
     def render(universe)
-      puts "\33c\e[3J" # Clears the screen and scrollback buffer.
-      puts universe.to_s
-      puts BANNER
+      # Use Alternate Screen (\e[?1049h) and move cursor to top left (\e[H)
+      # Ref: https://github.com/ruby/ruby/blob/ruby_2_7/lib/irb/easter-egg.rb#L112-L131
+      # Ref: https://stackoverflow.com/questions/11023929/using-the-alternate-screen-in-a-bash-script
+      # Ref: https://superuser.com/questions/122911/what-commands-can-i-use-to-reset-and-clear-my-terminal
+      print "\e[?1049h\e[H"
+      print universe.to_s
+      print BANNER
       sleep(DELAY / 1000.0)
     end
   end
diff --git a/CLI/ruby/spec/game_of_life_spec.rb b/CLI/ruby/spec/game_of_life_spec.rb
index 89a0c87..a0013a6 100644
--- a/CLI/ruby/spec/game_of_life_spec.rb
+++ b/CLI/ruby/spec/game_of_life_spec.rb
@@ -181,8 +181,8 @@ RSpec.describe GameOfLife do
     it "renders the game of life presentation" do
       stub_const("BANNER", "")
       stub_const("DELAY", 100.0)
-      expect_any_instance_of(Kernel).to receive(:puts).with("\33c\e[3J")
-      expect_any_instance_of(Kernel).to receive(:puts).twice
+      expect_any_instance_of(Kernel).to receive(:print).with("\e[?1049h\e[H")
+      expect_any_instance_of(Kernel).to receive(:print).twice
       expect(universe).to receive(:to_s)
       expect_any_instance_of(Kernel).to receive(:sleep)