[Fix #1340] Fix a false positive for Rails/WhereEquals when qualifying the database name

And `Rails/WhereNot`/``Rails/WhereRange` as well.

I'd like to extract some of this logic to a module sometime since it is looking rather similar.

The original issue mentions Redshift, and I know that MSSQL allows cross-database queries as well

Author: Earlopain

changelog/fix_false_positive_database_qualified.md

@@ -0,0 +1 @@
+* [#1340](https://github.com/rubocop/rubocop-rails/issues/1340): Fix a false positive for `Rails/WhereEquals`, `Rails/WhereNot`, and `Rails/WhereRange` when qualifying the database name. ([@earlopain][])

lib/rubocop/cop/rails/where_equals.rb

@@ -74,6 +74,7 @@ def offense_range(node)
           range_between(node.loc.selector.begin_pos, node.source_range.end_pos)
         end
 
+        # rubocop:disable Metrics/AbcSize, Metrics/CyclomaticComplexity, Metrics/MethodLength
         def extract_column_and_value(template_node, value_node)
           value =
             case template_node.value
@@ -90,8 +91,12 @@ def extract_column_and_value(template_node, value_node)
               return
             end
 
-          [Regexp.last_match(1), value]
+          column_qualifier = Regexp.last_match(1)
+          return if column_qualifier.count('.') > 1
+
+          [column_qualifier, value]
         end
+        # rubocop:enable Metrics/AbcSize, Metrics/CyclomaticComplexity, Metrics/MethodLength
 
         def build_good_method(method_name, column, value)
           if column.include?('.')

lib/rubocop/cop/rails/where_not.rb

@@ -68,6 +68,7 @@ def offense_range(node)
           range_between(node.loc.selector.begin_pos, node.source_range.end_pos)
         end
 
+        # rubocop:disable Metrics/AbcSize, Metrics/CyclomaticComplexity, Metrics/MethodLength
         def extract_column_and_value(template_node, value_node)
           value =
             case template_node.value
@@ -84,8 +85,12 @@ def extract_column_and_value(template_node, value_node)
               return
             end
 
-          [Regexp.last_match(1), value]
+          column_qualifier = Regexp.last_match(1)
+          return if column_qualifier.count('.') > 1
+
+          [column_qualifier, value]
         end
+        # rubocop:enable Metrics/AbcSize, Metrics/CyclomaticComplexity, Metrics/MethodLength
 
         def build_good_method(dot, column, value)
           dot ||= '.'

lib/rubocop/cop/rails/where_range.rb

@@ -140,6 +140,8 @@ def extract_column_and_value(template_node, values_node)
                 rhs = pair2.value
               end
             end
+          else
+            return
           end
 
           if lhs
@@ -150,7 +152,10 @@ def extract_column_and_value(template_node, values_node)
             rhs_source = parentheses_needed?(rhs) ? "(#{rhs.source})" : rhs.source
           end
 
-          [Regexp.last_match(1), "#{lhs_source}#{operator}#{rhs_source}"] if operator
+          column_qualifier = Regexp.last_match(1)
+          return if column_qualifier.count('.') > 1
+
+          [column_qualifier, "#{lhs_source}#{operator}#{rhs_source}"] if operator
         end
         # rubocop:enable Metrics
 

spec/rubocop/cop/rails/where_equals_spec.rb

@@ -217,4 +217,10 @@
       users.not('name = ?', 'Gabe')
     RUBY
   end
+
+  it 'does not register an offense when qualifying the database' do
+    expect_no_offenses(<<~RUBY)
+      User.where('database.users.name = ?', 'Gabe')
+    RUBY
+  end
 end

spec/rubocop/cop/rails/where_not_spec.rb

@@ -275,4 +275,10 @@
       User.where('name <> ? AND age <> ?', 'john', 19)
     RUBY
   end
+
+  it 'does not register an offense when qualifying the database' do
+    expect_no_offenses(<<~RUBY)
+      User.where('database.users.name != ?', 'Gabe')
+    RUBY
+  end
 end

spec/rubocop/cop/rails/where_range_spec.rb

@@ -221,6 +221,12 @@
           Model.where(column: ...value)
         RUBY
       end
+
+      it 'does not register an offense when qualifying the database' do
+        expect_no_offenses(<<~RUBY)
+          Model.where('database.table.column >= ?', value)
+        RUBY
+      end
     end
   end
 end