Fix LIKE predicates wildcard escaping for SQLite and other non-MySQL/PostgreSQL databases

lib/ransack/constants.rb

@@ -161,16 +161,8 @@ module Constants
   module_function
     # replace % \ to \% \\
     def escape_wildcards(unescaped)
-      case ActiveRecord::Base.connection.adapter_name
-      when "Mysql2".freeze
-        # Necessary for MySQL
-        unescaped.to_s.gsub(/([\\%_])/, '\\\\\\1')
-      when "PostGIS".freeze, "PostgreSQL".freeze
-        # Necessary for PostgreSQL
-        unescaped.to_s.gsub(/([\\%_.])/, '\\\\\\1')
-      else
-        unescaped
-      end
+      # Use ActiveRecord's sanitize_sql_like for consistent escaping across all adapters
+      ActiveRecord::Base.sanitize_sql_like(unescaped.to_s)
     end
   end
 end

lib/ransack/nodes/condition.rb

@@ -324,7 +324,13 @@ def combinator_method
       def format_predicate(attribute)
         arel_pred = arel_predicate_for_attribute(attribute)
         arel_values = formatted_values_for_attribute(attribute)
-        predicate = attr_value_for_attribute(attribute).public_send(arel_pred, arel_values)
+
+        # For LIKE predicates that use escaped wildcards, add ESCAPE clause for proper behavior
+        if needs_escape_clause?(arel_pred, arel_values)
+          predicate = attr_value_for_attribute(attribute).public_send(arel_pred, arel_values, '\\')
+        else
+          predicate = attr_value_for_attribute(attribute).public_send(arel_pred, arel_values)
+        end
 
         if in_predicate?(predicate)
           predicate.right = predicate.right.map do |pr|
@@ -364,6 +370,15 @@ def replace_right_node?(predicate)
       def valid_combinator?
         attributes.size < 2 || Constants::AND_OR.include?(combinator)
       end
+
+      def needs_escape_clause?(arel_pred, arel_values)
+        # Add ESCAPE clause for LIKE predicates when values contain escaped wildcards
+        like_predicates = ['matches', 'does_not_match']
+        return false unless like_predicates.include?(arel_pred.to_s)
+
+        # Check if any values contain escaped wildcards (backslash followed by %, _, or \)
+        Array(arel_values).any? { |val| val.to_s.match?(/\\[%_\\]/) }
+      end
     end
   end
 end

spec/ransack/predicate_spec.rb

@@ -21,6 +21,45 @@ module Ransack
       end
     end
 
+    describe 'wildcard escaping behavior' do
+      context 'with special characters in search values' do
+        it 'properly escapes wildcard characters in LIKE predicates' do
+          # Test that % and _ are treated as literal characters
+          Person.create!(name: '100% Pure')
+          Person.create!(name: '50_50 Blend')
+          Person.create!(name: 'Normal Text')
+
+          # Search for literal %
+          results = Person.ransack(name_cont: '%').result
+          expect(results).to include(Person.find_by(name: '100% Pure'))
+          expect(results).not_to include(Person.find_by(name: 'Normal Text'))
+
+          # Search for literal _
+          results = Person.ransack(name_cont: '_').result
+          expect(results).to include(Person.find_by(name: '50_50 Blend'))
+          expect(results).not_to include(Person.find_by(name: 'Normal Text'))
+        end
+
+        it 'works with start predicate' do
+          Person.create!(name: '%start')
+          Person.create!(name: 'normalstart')
+
+          results = Person.ransack(name_start: '%').result
+          expect(results).to include(Person.find_by(name: '%start'))
+          expect(results).not_to include(Person.find_by(name: 'normalstart'))
+        end
+
+        it 'works with end predicate' do
+          Person.create!(name: 'end%')
+          Person.create!(name: 'endnormal')
+
+          results = Person.ransack(name_end: '%').result
+          expect(results).to include(Person.find_by(name: 'end%'))
+          expect(results).not_to include(Person.find_by(name: 'endnormal'))
+        end
+      end
+    end
+
     describe 'eq' do
       it 'generates an equality condition for boolean true values' do
         test_boolean_equality_for(true)
@@ -163,7 +202,7 @@ module Ransack
         when "Mysql2"
           /`people`.`name` LIKE '%\\\\%.\\\\_\\\\\\\\%'/
         else
-         /"people"."name" LIKE '%%._\\%'/
+         /LIKE '%\\%\.\\_\\\\%' ESCAPE '\\'/
         end) do
         subject { @s }
       end
@@ -183,7 +222,7 @@ module Ransack
         when  "Mysql2"
           /`people`.`name` NOT LIKE '%\\\\%.\\\\_\\\\\\\\%'/
         else
-         /"people"."name" NOT LIKE '%%._\\%'/
+         /NOT LIKE '%\\%\.\\_\\\\%' ESCAPE '\\'/
         end) do
         subject { @s }
       end
@@ -205,7 +244,7 @@ module Ransack
         when "Mysql2"
           /LOWER\(`people`.`name`\) LIKE '%\\\\%.\\\\_\\\\\\\\%'/
         else
-         /LOWER\("people"."name"\) LIKE '%%._\\%'/
+         /LIKE '%\\%\.\\_\\\\%' ESCAPE '\\'/
         end) do
         subject { @s }
       end
@@ -227,7 +266,7 @@ module Ransack
         when "Mysql2"
           /LOWER\(`people`.`name`\) NOT LIKE '%\\\\%.\\\\_\\\\\\\\%'/
         else
-         /LOWER\("people"."name"\) NOT LIKE '%%._\\%'/
+         /NOT LIKE '%\\%\.\\_\\\\%' ESCAPE '\\'/
         end) do
         subject { @s }
       end