Merge pull request #1008 from samrjenkins/fix-uniqueness-validation-without-index-explicit-disable

Fix `Rails/UniquenessValidationWithoutIndex` false positive on explicit disable

Author: koic

changelog/fix_uniqueness_validation_without_index_explicit_disable_false_positive.md

@@ -0,0 +1 @@
+* [#1008](https://github.com/rubocop/rubocop-rails/pull/1008): Fix `UniqueValidationWithoutIndex` to not detect offenses when a validation specifies `uniqueness: false`. ([@samrjenkins][])

lib/rubocop/cop/rails/unique_validation_without_index.rb

@@ -31,7 +31,7 @@ class UniqueValidationWithoutIndex < Base
         RESTRICT_ON_SEND = %i[validates].freeze
 
         def on_send(node)
-          return unless uniqueness_part(node)
+          return if uniqueness_part(node).falsey_literal?
           return if condition_part?(node)
           return unless schema
 

spec/rubocop/cop/rails/unique_validation_without_index_spec.rb

@@ -32,6 +32,14 @@ class User
           end
         RUBY
       end
+
+      it 'does not register an offense' do
+        expect_no_offenses(<<~RUBY)
+          class User
+            validates :account, uniqueness: false
+          end
+        RUBY
+      end
     end
 
     context 'when the table has an index but it is not unique' do