Merge pull request #1646 from pablonahuelgomez/allow-helpers-to-mix-in-a-list-of-modules

Add ability to include an array of modules as helpers

Author: dblock

CHANGELOG.md

@@ -5,6 +5,7 @@
 * [#1594](https://github.com/ruby-grape/grape/pull/1594): Replace `Hashie::Mash` parameters with `ActiveSupport::HashWithIndifferentAccess` - [@james2m](https://github.com/james2m), [@dblock](https://github.com/dblock).
 * [#1622](https://github.com/ruby-grape/grape/pull/1622): Add `except_values` validator to replace `except` option of `values` validator - [@jlfaber](https://github.com/jlfaber).
 * [#1635](https://github.com/ruby-grape/grape/pull/1635): Instrument validators with ActiveSupport::Notifications - [@ktimothy](https://github.com/ktimothy).
+* [#1646](https://github.com/ruby-grape/grape/pull/1646): Add ability to include an array of modules as helpers - [@pablonahuelgomez](https://github.com/pablonahuelgomez).
 * Your contribution here.
 
 #### Fixes

lib/grape/dsl/helpers.rb

@@ -13,7 +13,7 @@ module ClassMethods
         # When called without a block, all known helpers within this scope
         # are included.
         #
-        # @param [Module] new_mod optional module of methods to include
+        # @param [Array] new_modules optional array of modules to include
         # @param [Block] block optional block of methods to include
         #
         # @example Define some helpers.
@@ -26,28 +26,42 @@ module ClassMethods
         #       end
         #     end
         #
-        def helpers(new_mod = nil, &block)
-          if block_given? || new_mod
-            mod = new_mod || Module.new
-            define_boolean_in_mod(mod)
-            inject_api_helpers_to_mod(mod) if new_mod
+        # @example Include many modules
+        #
+        #     class ExampleAPI < Grape::API
+        #       helpers Authentication, Mailer, OtherModule
+        #     end
+        #
+        def helpers(*new_modules, &block)
+          include_new_modules(new_modules) if new_modules.any?
+          include_block(block) if block_given?
+          include_all_in_scope if !block_given? && new_modules.empty?
+        end
 
-            inject_api_helpers_to_mod(mod) do
-              mod.class_eval(&block)
-            end if block_given?
+        protected
 
-            namespace_stackable(:helpers, mod)
-          else
-            mod = Module.new
-            namespace_stackable(:helpers).each do |mod_to_include|
-              mod.send :include, mod_to_include
-            end
-            change!
-            mod
+        def include_new_modules(modules)
+          modules.each { |mod| make_inclusion(mod) }
+        end
+
+        def include_block(block)
+          Module.new.tap do |mod|
+            make_inclusion(mod) { mod.class_eval(&block) }
           end
         end
 
-        protected
+        def make_inclusion(mod, &block)
+          define_boolean_in_mod(mod)
+          inject_api_helpers_to_mod(mod, &block)
+          namespace_stackable(:helpers, mod)
+        end
+
+        def include_all_in_scope
+          Module.new.tap do |mod|
+            namespace_stackable(:helpers).each { |mod_to_include| mod.send :include, mod_to_include }
+            change!
+          end
+        end
 
         def define_boolean_in_mod(mod)
           return if defined? mod::Boolean

spec/grape/dsl/helpers_spec.rb

@@ -6,8 +6,12 @@ module HelpersSpec
       class Dummy
         include Grape::DSL::Helpers
 
-        def self.mod
-          namespace_stackable(:helpers).first
+        def self.mods
+          namespace_stackable(:helpers)
+        end
+
+        def self.first_mod
+          mods.first
         end
       end
     end
@@ -36,23 +40,38 @@ def test
           expect(subject).to receive(:namespace_stackable).with(:helpers).and_call_original
           subject.helpers(&proc)
 
-          expect(subject.mod.instance_methods).to include(:test)
+          expect(subject.first_mod.instance_methods).to include(:test)
         end
 
         it 'uses provided modules' do
           mod = Module.new
 
-          expect(subject).to receive(:namespace_stackable).with(:helpers, kind_of(Grape::DSL::Helpers::BaseHelper)).and_call_original
+          expect(subject).to receive(:namespace_stackable).with(:helpers, kind_of(Grape::DSL::Helpers::BaseHelper)).and_call_original.exactly(2).times
           expect(subject).to receive(:namespace_stackable).with(:helpers).and_call_original
           subject.helpers(mod, &proc)
 
-          expect(subject.mod).to eq mod
+          expect(subject.first_mod).to eq mod
+        end
+
+        it 'uses many provided modules' do
+          mod  = Module.new
+          mod2 = Module.new
+          mod3 = Module.new
+
+          expect(subject).to receive(:namespace_stackable).with(:helpers, kind_of(Grape::DSL::Helpers::BaseHelper)).and_call_original.exactly(4).times
+          expect(subject).to receive(:namespace_stackable).with(:helpers).and_call_original.exactly(3).times
+
+          subject.helpers(mod, mod2, mod3, &proc)
+
+          expect(subject.mods).to include(mod)
+          expect(subject.mods).to include(mod2)
+          expect(subject.mods).to include(mod3)
         end
 
         context 'with an external file' do
           it 'sets Boolean as a Virtus::Attribute::Boolean' do
             subject.helpers BooleanParam
-            expect(subject.mod::Boolean).to eq Virtus::Attribute::Boolean
+            expect(subject.first_mod::Boolean).to eq Virtus::Attribute::Boolean
           end
         end
       end