Add a --relock option to bundle install

lib/bundler/cli.rb

@@ -44,15 +44,20 @@ def check
     end
 
     desc "install", "Install the current environment to the system"
-    method_option :without, :type => :array, :banner => "Exclude gems that are part of the specified named group"
+    method_option :without, :type => :array, :banner   => "Exclude gems that are part of the specified named group"
+    method_option :relock,  :type => :boolean, :banner => "Unlock, install the gems, and relock"
     def install(path = nil)
+      remove_lockfiles if options[:relock]
+
       opts = options.dup
       opts[:without] ||= []
       opts[:without].map! { |g| g.to_sym }
 
       Bundler.settings[:path] = path if path
 
       Installer.install(Bundler.root, Bundler.definition, opts)
+
+      lock if options[:relock]
     end
 
     desc "lock", "Locks the bundle to the current set of dependencies, including all child dependencies."

spec/install/gems_spec.rb

@@ -157,18 +157,27 @@
   end
 
   describe "when locked" do
-    it "works" do
-      system_gems "rack-1.0.0" do
+    before(:each) do
+      system_gems "rack-0.9.1" do
         gemfile <<-G
           source "file://#{gem_repo1}"
           gem "rack"
         G
 
         bundle :lock
       end
+    end
 
+    it "works" do
       system_gems [] do
         bundle :install
+        should_be_installed "rack 0.9.1"
+      end
+    end
+
+    it "allows --relock to update the dependencies" do
+      system_gems "rack-0.9.1" do
+        bundle "install --relock"
         should_be_installed "rack 1.0.0"
       end
     end