Implementation of remove.

CHANGELOG.md

@@ -6,6 +6,7 @@ Reverse Chronological Order:
 
 https://github.com/capistrano/capistrano/compare/v3.4.0...HEAD
 
+* `remove` DSL method for removing values like from arrays like `linked_dirs`
 * `append` DSL method for pushing values like `linked_dirs`
   [#1447](https://github.com/capistrano/capistrano/pull/1447),
   [#1586](https://github.com/capistrano/capistrano/pull/1586)

lib/capistrano/configuration.rb

@@ -28,7 +28,7 @@ module Capistrano
     def set(key, value=nil, &block)
       invoke_validations(key, value, &block)
       config[key] = block || value
-      
+
       puts "Config variable set: #{key.inspect} => #{config[key].inspect}" if fetch(:print_config_variables, false)
 
       config[key]
@@ -42,6 +42,10 @@ module Capistrano
       set(key, Array(fetch(key)).concat(values))
     end
 
+    def remove(key, *values)
+      set(key, Array(fetch(key)) - values)
+    end
+
     def delete(key)
       config.delete(key)
     end

lib/capistrano/dsl/env.rb

@@ -6,7 +6,7 @@ module Capistrano
       extend Forwardable
       def_delegators :env,
                      :configure_backend, :fetch, :set, :set_if_empty, :delete,
-                     :ask, :role, :server, :primary, :validate, :append
+                     :ask, :role, :server, :primary, :validate, :append, :remove
 
       def is_question?(key)
         env.is_question?(key)

spec/lib/capistrano/configuration_spec.rb

@@ -175,6 +175,38 @@ module Capistrano
           end
         end
       end
+
+      context 'removing' do
+        before :each do
+          config.set(:linked_dirs, ['vendor/bundle', 'tmp'])
+        end
+
+        subject { config.remove(:linked_dirs, 'vendor/bundle') }
+
+        it 'returns without removed value' do
+          expect(subject).to eq ['tmp']
+        end
+
+        context 'on non-array variable' do
+          before { config.set(:linked_dirs, 'string') }
+
+          context 'when removing same value' do
+            subject { config.remove(:linked_dirs, 'string') }
+
+            it 'returns without removed value' do
+              expect(subject).to eq []
+            end
+          end
+
+          context 'when removing different value' do
+            subject { config.remove(:linked_dirs, 'othervalue') }
+
+            it 'returns without removed value' do
+              expect(subject).to eq ['string']
+            end
+          end
+        end
+      end
     end
 
     describe 'keys' do