bottle: only chdir into the cellar when tarring up the bottle

Library/Homebrew/cmd/bottle.rb

@@ -127,14 +127,10 @@ module Homebrew extend self
     end
 
     bottle_path = Pathname.pwd/filename
-    sha1 = nil
 
     prefix = HOMEBREW_PREFIX.to_s
     cellar = HOMEBREW_CELLAR.to_s
 
-    output = nil
-
-    HOMEBREW_CELLAR.cd do
     ohai "Bottling #{filename}..."
 
     keg = Keg.new(f.prefix)
@@ -145,9 +141,11 @@ module Homebrew extend self
         keg.relocate_install_names prefix, Keg::PREFIX_PLACEHOLDER,
           cellar, Keg::CELLAR_PLACEHOLDER, :keg_only => f.keg_only?
 
+        HOMEBREW_CELLAR.cd do
           # Use gzip, faster to compress than bzip2, faster to uncompress than bzip2
           # or an uncompressed tarball (and more bandwidth friendly).
           safe_system 'tar', 'czf', bottle_path, "#{f.name}/#{f.version}"
+        end
 
         if File.size?(bottle_path) > 1*1024*1024
           ohai "Detecting if #{filename} is relocatable..."
@@ -172,18 +170,16 @@ module Homebrew extend self
       end
     end
 
-      sha1 = bottle_path.sha1
-
     bottle = Bottle.new
     bottle.prefix HOMEBREW_PREFIX
     bottle.cellar relocatable ? :any : HOMEBREW_CELLAR
     bottle.revision bottle_revision
-      bottle.sha1 sha1 => bottle_tag
+    bottle.sha1 bottle_path.sha1 => bottle_tag
+
+    output = bottle_output bottle
 
     puts "./#{filename}"
-      output = bottle_output bottle
     puts output
-    end
 
     if ARGV.include? '--rb'
       bottle_base = filename.gsub(bottle_suffix(bottle_revision), '')