Support multiple groups

README.md

@@ -93,7 +93,7 @@ The following types are supported:
 
 ### Groups
 
-Groups give you more flexibility to define when variables are needed.  
+Groups give you more flexibility to define when variables are needed.
 It's similar to groups in a Gemfile:
 
 ```ruby
@@ -103,6 +103,10 @@ variable :FORCE_SSL, :boolean
 group :production do
   variable :SECRET_KEY_BASE
 end
+
+group :development, :staging do
+  variable :DEV_KEY
+end
 ```
 
 ```ruby
@@ -142,7 +146,7 @@ variable :PORT, :integer, default: proc {|envied| envied.FORCE_SSL ? 443 : 80 }
 ```
 
 Please remember that ENVied only **reads** from ENV; it doesn't mutate ENV.
-Don't let setting a default for, say `RAILS_ENV`, give you the impression that `ENV['RAILS_ENV']` is set.  
+Don't let setting a default for, say `RAILS_ENV`, give you the impression that `ENV['RAILS_ENV']` is set.
 As a rule of thumb you should only use defaults:
 * for local development
 * for ENV-variables that are solely used by your application (i.e. for `ENV['STAFF_EMAILS']`, not for `ENV['RAILS_ENV']`)

lib/envied/configuration.rb

@@ -45,9 +45,11 @@ def variable(name, *args)
       variables << ENVied::Variable.new(name, type, options)
     end
 
-    def group(name, &block)
-      @current_group = name.to_sym
-      yield
+    def group(*names, &block)
+      names.each do |name|
+        @current_group = name.to_sym
+        yield
+      end
     ensure
       @current_group = nil
     end

spec/envied_spec.rb

@@ -283,6 +283,28 @@ def envied_require(*args)
         end
       end
 
+      context 'a variable in multiple groups' do
+        before do
+          configure do
+            variable :moar
+
+            group :foo, :moo do
+              variable :bar
+            end
+          end.and_no_ENV
+        end
+
+        it 'is required when requiring any of the groups' do
+          expect {
+            envied_require(:foo)
+          }.to raise_error(/bar/)
+
+          expect {
+            envied_require(:moo)
+          }.to raise_error(/bar/)
+        end
+      end
+
       describe 'Hashable' do
         before do
           configure do