Allow to use regexp validator with arrays

Author: Alexander Koltun

CHANGELOG.md

@@ -1,6 +1,7 @@
 0.17.1 (Next)
 ==================
 
+* [#1503](https://github.com/ruby-grape/grape/pull/1503): Allow to use regexp validator with arrays - [@akoltun](https://github.com/akoltun).
 * [#1480](https://github.com/ruby-grape/grape/pull/1480): Use the ruby-grape-danger gem for PR linting - [@dblock](https://github.com/dblock).
 * [#1486](https://github.com/ruby-grape/grape/pull/1486): Implemented except in values validator - [@jonmchan](https://github.com/jonmchan).
 * [#1470](https://github.com/ruby-grape/grape/pull/1470): Drop support for ruby-2.0 - [@namusyaka](https://github.com/namusyaka).

lib/grape/validations/validators/regexp.rb

@@ -2,7 +2,7 @@ module Grape
   module Validations
     class RegexpValidator < Base
       def validate_param!(attr_name, params)
-        return unless params.key?(attr_name) && !params[attr_name].nil? && !(params[attr_name].to_s =~ (options_key?(:value) ? @option[:value] : @option))
+        return if Array.wrap(params[attr_name]).all? { |param| param.nil? || (param.to_s =~ (options_key?(:value) ? @option[:value] : @option)) }
         raise Grape::Exceptions::Validation, params: [@scope.full_name(attr_name)], message: message(:regexp)
       end
     end

spec/grape/validations/validators/regexp_spec.rb

@@ -12,13 +12,25 @@ class API < Grape::API
           end
           get do
           end
+
+          params do
+            requires :names, type: { value: Array[String], message: 'can\'t be nil' }, regexp: { value: /^[a-z]+$/, message: 'format is invalid' }
+          end
+          get 'regexp_with_array' do
+          end
         end
 
         params do
           requires :name, regexp: /^[a-z]+$/
         end
         get do
         end
+
+        params do
+          requires :names, type: Array[String], regexp: /^[a-z]+$/
+        end
+        get 'regexp_with_array' do
+        end
       end
     end
   end
@@ -51,6 +63,36 @@ def app
       get '/custom_message', name: 'bob'
       expect(last_response.status).to eq(200)
     end
+
+    context 'regexp with array' do
+      it 'refuses inapppopriate items' do
+        get '/custom_message/regexp_with_array', names: ['invalid name', 'abc']
+        expect(last_response.status).to eq(400)
+        expect(last_response.body).to eq('{"error":"names format is invalid"}')
+      end
+
+      it 'refuses empty items' do
+        get '/custom_message/regexp_with_array', names: ['', 'abc']
+        expect(last_response.status).to eq(400)
+        expect(last_response.body).to eq('{"error":"names format is invalid"}')
+      end
+
+      it 'refuses nil items' do
+        get '/custom_message/regexp_with_array', names: [nil, 'abc']
+        expect(last_response.status).to eq(400)
+        expect(last_response.body).to eq('{"error":"names can\'t be nil"}')
+      end
+
+      it 'accepts valid items' do
+        get '/custom_message/regexp_with_array', names: ['bob']
+        expect(last_response.status).to eq(200)
+      end
+
+      it 'accepts nil instead of array' do
+        get '/custom_message/regexp_with_array', names: nil
+        expect(last_response.status).to eq(200)
+      end
+    end
   end
 
   context 'invalid input' do
@@ -76,4 +118,34 @@ def app
     get '/', name: 'bob'
     expect(last_response.status).to eq(200)
   end
+
+  context 'regexp with array' do
+    it 'refuses inapppopriate items' do
+      get '/regexp_with_array', names: ['invalid name', 'abc']
+      expect(last_response.status).to eq(400)
+      expect(last_response.body).to eq('{"error":"names is invalid"}')
+    end
+
+    it 'refuses empty items' do
+      get '/regexp_with_array', names: ['', 'abc']
+      expect(last_response.status).to eq(400)
+      expect(last_response.body).to eq('{"error":"names is invalid"}')
+    end
+
+    it 'refuses nil items' do
+      get '/regexp_with_array', names: [nil, 'abc']
+      expect(last_response.status).to eq(400)
+      expect(last_response.body).to eq('{"error":"names is invalid"}')
+    end
+
+    it 'accepts valid items' do
+      get '/regexp_with_array', names: ['bob']
+      expect(last_response.status).to eq(200)
+    end
+
+    it 'accepts nil instead of array' do
+      get '/regexp_with_array', names: nil
+      expect(last_response.status).to eq(200)
+    end
+  end
 end