Make updating sources a noop in bundle install if all of the gems are…

… already available

lib/bundler/cli.rb

@@ -139,7 +139,7 @@ def update(*gems)
         Bundler.definition(:gems => gems, :sources => sources)
       end
 
-      Installer.install Bundler.root, Bundler.definition
+      Installer.install Bundler.root, Bundler.definition, "update" => true
       cache if Bundler.root.join("vendor/cache").exist?
       Bundler.ui.confirm "Your bundle is updated! " +
         "Use `bundle show [gemname]` to see where a bundled gem is installed."

lib/bundler/installer.rb

@@ -15,11 +15,21 @@ def run(options)
         return
       end
 
+      if Bundler.root.join("Gemfile.lock").exist? && !options["update"]
+        begin
+          missing_specs = Definition.build(Bundler.default_gemfile, Bundler.root.join("Gemfile.lock"), nil).missing_specs
+          local = true unless missing_specs.any?
+        rescue BundlerError
+        end
+      end
+
       # Since we are installing, we can resolve the definition
       # using remote specs
-      options["local"] ?
-        @definition.resolve_with_cache! :
-        @definition.resolve_remotely!
+      unless local
+        options["local"] ?
+          @definition.resolve_with_cache! :
+          @definition.resolve_remotely!
+      end
 
       # Ensure that BUNDLE_PATH exists
       Bundler.mkdir_p(Bundler.bundle_path)

lib/bundler/source.rb

@@ -544,7 +544,8 @@ def install(spec)
       end
 
       def load_spec_files
-        super if cache_path.exist?
+        return super if cache_path.exist?
+        raise PathError
       rescue PathError
         raise PathError, "#{to_s} is not checked out. Please run `bundle install`"
       end