AtLeastOneOfValidator properly treats nested params in errors

Unlike other validators `Grape::Valiations::AtLeastOneOfValidator` didn't wrap params
into a scope (namespace) for errors when params were nested.

CHANGELOG.md

@@ -8,6 +8,7 @@
 #### Fixes
 
 * Your contribution here.
+* [#1911](https://github.com/ruby-grape/grape/pull/1911): Make sure `Grape::Valiations::AtLeastOneOfValidator` properly treats nested params in errors - [@dnesteryuk](https://github.com/dnesteryuk).
 * [#1893](https://github.com/ruby-grape/grape/pull/1893): Allows `Grape::API` to behave like a Rack::app in some instances where it was misbehaving - [@myxoh](https://github.com/myxoh).
 * [#1898](https://github.com/ruby-grape/grape/pull/1898): Refactor `ValidatorFactory` to improve memory allocation - [@Bhacaz](https://github.com/Bhacaz).
 * [#1900](https://github.com/ruby-grape/grape/pull/1900): Define boolean for `Grape::Api::Instance` - [@Bhacaz](https://github.com/Bhacaz).
@@ -17,7 +18,7 @@
 
 #### Features
 
-* [#1888](https://github.com/ruby-grape/grape/pull/1888): Makes the `configuration` hash widly available - [@myxoh](https://github.com/myxoh).
+* [#1888](https://github.com/ruby-grape/grape/pull/1888): Makes the `configuration` hash widely available - [@myxoh](https://github.com/myxoh).
 * [#1864](https://github.com/ruby-grape/grape/pull/1864): Adds `finally` on the API - [@myxoh](https://github.com/myxoh).
 * [#1869](https://github.com/ruby-grape/grape/pull/1869): Fix issue with empty headers after `error!` method call - [@anaumov](https://github.com/anaumov).
 

lib/grape/validations/validators/at_least_one_of.rb

@@ -1,11 +1,14 @@
+require 'grape/validations/validators/multiple_params_base'
+
 module Grape
   module Validations
-    require 'grape/validations/validators/multiple_params_base'
     class AtLeastOneOfValidator < MultipleParamsBase
       def validate!(params)
         super
         if scope_requires_params && no_exclusive_params_are_present
-          raise Grape::Exceptions::Validation, params: all_keys, message: message(:at_least_one)
+          scoped_params = all_keys.map { |key| @scope.full_name(key) }
+          raise Grape::Exceptions::Validation, params: scoped_params,
+                                               message: message(:at_least_one)
         end
         params
       end

spec/grape/validations/validators/at_least_one_of_spec.rb

@@ -9,8 +9,15 @@ def params(arg)
         end
 
         def required?; end
+
+        # mimics a method from Grape::Validations::ParamsScope which decides how a parameter must
+        # be named in errors
+        def full_name(name)
+          "food[#{name}]"
+        end
       end
     end
+
     let(:at_least_one_of_params) { %i[beer wine grapefruit] }
     let(:validator) { described_class.new(at_least_one_of_params, {}, false, scope.new) }
 
@@ -48,11 +55,14 @@ def required?; end
 
     context 'when none of the restricted params is selected' do
       let(:params) { { somethingelse: true } }
-
       it 'raises a validation exception' do
-        expect do
-          validator.validate! params
-        end.to raise_error(Grape::Exceptions::Validation)
+        expected_params = at_least_one_of_params.map { |p| "food[#{p}]" }
+
+        expect { validator.validate! params }.to raise_error do |error|
+          expect(error).to be_a(Grape::Exceptions::Validation)
+          expect(error.params).to eq(expected_params)
+          expect(error.message).to eq(I18n.t('grape.errors.messages.at_least_one'))
+        end
       end
     end
 

spec/grape/validations_spec.rb

@@ -1485,16 +1485,16 @@ def validate_param!(attr_name, params)
         before :each do
           subject.params do
             requires :nested, type: Hash do
-              optional :beer_nested
-              optional :wine_nested
-              optional :juice_nested
-              at_least_one_of :beer_nested, :wine_nested, :juice_nested
+              optional :beer
+              optional :wine
+              optional :juice
+              at_least_one_of :beer, :wine, :juice
             end
             optional :nested2, type: Array do
-              optional :beer_nested2
-              optional :wine_nested2
-              optional :juice_nested2
-              at_least_one_of :beer_nested2, :wine_nested2, :juice_nested2
+              optional :beer
+              optional :wine
+              optional :juice
+              at_least_one_of :beer, :wine, :juice
             end
           end
           subject.get '/at_least_one_of_nested' do
@@ -1505,17 +1505,17 @@ def validate_param!(attr_name, params)
         it 'errors when none are present' do
           get '/at_least_one_of_nested'
           expect(last_response.status).to eq(400)
-          expect(last_response.body).to eq 'nested is missing, beer_nested, wine_nested, juice_nested are missing, at least one parameter must be provided'
+          expect(last_response.body).to eq 'nested is missing, nested[beer], nested[wine], nested[juice] are missing, at least one parameter must be provided'
         end
 
         it 'does not error when one is present' do
-          get '/at_least_one_of_nested', nested: { beer_nested: 'string' }, nested2: [{ beer_nested2: 'string' }]
+          get '/at_least_one_of_nested', nested: { beer: 'string' }, nested2: [{ beer: 'string' }]
           expect(last_response.status).to eq(200)
           expect(last_response.body).to eq 'at_least_one_of works!'
         end
 
         it 'does not error when two are present' do
-          get '/at_least_one_of_nested', nested: { beer_nested: 'string', wine_nested: 'string' }, nested2: [{ beer_nested2: 'string', wine_nested2: 'string' }]
+          get '/at_least_one_of_nested', nested: { beer: 'string', wine: 'string' }, nested2: [{ beer: 'string', wine: 'string' }]
           expect(last_response.status).to eq(200)
           expect(last_response.body).to eq 'at_least_one_of works!'
         end