emoji: extract logic into generic OS classes. (#450)

Library/Homebrew/emoji.rb

+module Emoji
+  class << self
+    def tick
+      # necessary for 1.8.7 unicode handling since many installs are on 1.8.7
+      @tick ||= ["2714".hex].pack("U*")
+    end
+
+    def cross
+      # necessary for 1.8.7 unicode handling since many installs are on 1.8.7
+      @cross ||= ["2718".hex].pack("U*")
+    end
+
+    def install_badge
+      ENV["HOMEBREW_INSTALL_BADGE"] || "\xf0\x9f\x8d\xba"
+    end
+
+    def enabled?
+      !ENV["HOMEBREW_NO_EMOJI"]
+    end
+    alias generic_enabled? enabled?
+  end
+end
+
+require "extend/os/emoji"

Library/Homebrew/extend/os/emoji.rb

+require "os"
+require "emoji"
+
+if OS.mac?
+  require "extend/os/mac/emoji"
+end

Library/Homebrew/extend/os/mac/emoji.rb

+module Emoji
+  class << self
+    def enabled?
+      generic_enabled? && MacOS.version >= :lion
+    end
+  end
+end

Library/Homebrew/formula_installer.rb

@@ -13,6 +13,7 @@ require "hooks/bottles"
 require "debrew"
 require "sandbox"
 require "requirements/cctools_requirement"
+require "emoji"
 
 class FormulaInstaller
   include FormulaCellarChecks
@@ -492,13 +493,9 @@ class FormulaInstaller
     unlock
   end
 
-  def emoji
-    ENV["HOMEBREW_INSTALL_BADGE"] || "\xf0\x9f\x8d\xba"
-  end
-
   def summary
     s = ""
-    s << "#{emoji}  " if MacOS.version >= :lion && !ENV["HOMEBREW_NO_EMOJI"]
+    s << "#{Emoji.install_badge}  " if Emoji.enabled?
     s << "#{formula.prefix}: #{formula.prefix.abv}"
     s << ", built in #{pretty_duration build_time}" if build_time
     s

Library/Homebrew/utils.rb

 require "pathname"
+require "emoji"
 require "exceptions"
 require "utils/hash"
 require "utils/json"
@@ -12,16 +13,6 @@ require "utils/curl"
 
 class Tty
   class << self
-    def tick
-      # necessary for 1.8.7 unicode handling since many installs are on 1.8.7
-      @tick ||= ["2714".hex].pack("U*")
-    end
-
-    def cross
-      # necessary for 1.8.7 unicode handling since many installs are on 1.8.7
-      @cross ||= ["2718".hex].pack("U*")
-    end
-
     def strip_ansi(string)
       string.gsub(/\033\[\d+(;\d+)*m/, "")
     end
@@ -124,20 +115,20 @@ end
 def pretty_installed(f)
   if !$stdout.tty?
     "#{f}"
-  elsif ENV["HOMEBREW_NO_EMOJI"]
-    "#{Tty.highlight}#{Tty.green}#{f} (installed)#{Tty.reset}"
+  elsif Emoji.enabled?
+    "#{Tty.highlight}#{f} #{Tty.green}#{Emoji.tick}#{Tty.reset}"
   else
-    "#{Tty.highlight}#{f} #{Tty.green}#{Tty.tick}#{Tty.reset}"
+    "#{Tty.highlight}#{Tty.green}#{f} (installed)#{Tty.reset}"
   end
 end
 
 def pretty_uninstalled(f)
   if !$stdout.tty?
     "#{f}"
-  elsif ENV["HOMEBREW_NO_EMOJI"]
-    "#{Tty.red}#{f} (uninstalled)#{Tty.reset}"
+  elsif Emoji.enabled?
+    "#{f} #{Tty.red}#{Emoji.cross}#{Tty.reset}"
   else
-    "#{f} #{Tty.red}#{Tty.cross}#{Tty.reset}"
+    "#{Tty.red}#{f} (uninstalled)#{Tty.reset}"
   end
 end