Allow clearing --without groups

fixes rubygems#1259

lib/bundler/cli.rb

@@ -150,12 +150,11 @@ def check
       "Install using defaults tuned for deployment environments"
     def install(path = nil)
       opts = options.dup
-      opts[:without] ||= []
-      if opts[:without].size == 1
-        opts[:without] = opts[:without].map{|g| g.split(" ") }
+      if opts[:without]
+        opts[:without].map!{|g| g.split(" ") }
         opts[:without].flatten!
+        opts[:without].map!{|g| g.to_sym }
       end
-      opts[:without] = opts[:without].map{|g| g.to_sym }
 
       # Can't use Bundler.settings for this because settings needs gemfile.dirname
       ENV['BUNDLE_GEMFILE'] = File.expand_path(opts[:gemfile]) if opts[:gemfile]
@@ -214,7 +213,7 @@ def install(path = nil)
       Bundler.settings[:bin] = opts["binstubs"] if opts[:binstubs]
       Bundler.settings[:no_prune] = true if opts["no-prune"]
       Bundler.settings[:disable_shared_gems] = Bundler.settings[:path] ? '1' : nil
-      Bundler.settings.without = opts[:without] unless opts[:without].empty?
+      Bundler.settings.without = opts[:without]
       Bundler.ui.be_quiet! if opts[:quiet]
 
       Installer.install(Bundler.root, Bundler.definition, opts)

lib/bundler/settings.rb

@@ -62,9 +62,7 @@ def pretty_values_for(exposed_key)
     end
 
     def without=(array)
-      unless array.empty?
-        self[:without] = array.join(":")
-      end
+      self[:without] = (array.empty? ? nil : array.join(":")) if array
     end
 
     def without
@@ -95,6 +93,7 @@ def key_for(key)
 
     def set_key(key, value, hash, file)
       key = key_for(key)
+      puts key.inspect
 
       unless hash[key] == value
         hash[key] = value

spec/install/gems/groups_spec.rb

@@ -136,6 +136,20 @@
 
           ENV["BUNDLE_WITHOUT"] = nil
         end
+
+        it "clears without when passed an empty list" do
+          bundle :install, :without => "emo"
+
+          bundle 'install --without ""'
+          should_be_installed "activesupport 2.3.5"
+        end
+
+        it "doesn't clear without when nothing is passed" do
+          bundle :install, :without => "emo"
+
+          bundle :install
+          should_not_be_installed "activesupport 2.3.5"
+        end
       end
 
       describe "with gems assigned to multiple groups" do