Implement optional groups

* Add optional option to the group method, defaulting to false
* Exclude optional groups from the groups to be installed
* Add --with parameter to bundle install to install a group that would
* otherwise be excluded
* Error out if a group is listed in both, --with and --without
* Add bundle_with option to capistrano task

2 files changed, 14 insertions, 1 deletions

diff --git a/man/bundle-install.ronn b/man/bundle-install.ronn
index e9706b51..117fd363 100644
--- a/man/bundle-install.ronn
+++ b/man/bundle-install.ronn
@@ -18,6 +18,7 @@ bundle-install(1) -- Install the dependencies specified in your Gemfile
                  [--standalone[=GROUP[ GROUP...]]]
                  [--trust-policy=POLICY]
                  [--without=GROUP[ GROUP...]]
+                 [--with=GROUP[ GROUP...]]
 
 ## DESCRIPTION
 
@@ -125,8 +126,16 @@ update process below under [CONSERVATIVE UPDATING][].
 
 * `--without=<list>`:
   A space-separated list of groups referencing gems to skip during installation.
+  If a group is given that is in the remembered list of groups given
+  to --with, it is removed from that list.
   This is a [remembered option][REMEMBERED OPTIONS].
 
+* `--with=<list>`:
+  A space-separated list of groups referencing gems to install. If an
+  optional group is given it is installed. If a group is given that is
+  in the remembered list of groups given to --without, it is removed
+  from that list. This is a [remembered option][REMEMBERED OPTIONS].
+
 
 ## DEPLOYMENT MODE
 
diff --git a/man/gemfile.5.ronn b/man/gemfile.5.ronn
index 876c9273..dcd1961a 100644
--- a/man/gemfile.5.ronn
+++ b/man/gemfile.5.ronn
@@ -430,11 +430,15 @@ applied to a group of gems by using block form.
       gem "sqlite3"
     end
 
-    group :development do
+    group :development, :optional => true do
       gem "wirble"
       gem "faker"
     end
 
+In the case of the group block form the :optional option can be given
+to prevent a group from being installed unless listed in the `--with`
+option given to the `bundle install` command.
+
 In the case of the `git` block form, the `:ref`, `:branch`, `:tag`,
 and `:submodules` options may be passed to the `git` method, and
 all gems in the block will inherit those options.