support LIKE case-insensitive matching

lib/arel/visitors/oracle.rb

@@ -1,8 +1,12 @@
 # frozen_string_literal: true
 
+require_relative "oracle_common"
+
 module Arel # :nodoc: all
   module Visitors
     class Oracle < Arel::Visitors::ToSql
+      include OracleCommon
+
       private
         def visit_Arel_Nodes_SelectStatement(o, collector)
           o = order_hacks(o)

lib/arel/visitors/oracle12.rb

@@ -1,8 +1,12 @@
 # frozen_string_literal: true
 
+require_relative "oracle_common"
+
 module Arel # :nodoc: all
   module Visitors
     class Oracle12 < Arel::Visitors::ToSql
+      include OracleCommon
+
       private
         def visit_Arel_Nodes_SelectStatement(o, collector)
           # Oracle does not allow LIMIT clause with select for update

lib/arel/visitors/oracle_common.rb

@@ -0,0 +1,17 @@
+# frozen_string_literal: true
+
+module Arel # :nodoc: all
+  module Visitors
+    module OracleCommon
+      private
+        def visit_Arel_Nodes_Matches(o, collector)
+          if !o.case_sensitive && o.left && o.right
+            o.left = Arel::Nodes::NamedFunction.new("UPPER", [o.left])
+            o.right = Arel::Nodes::NamedFunction.new("UPPER", [o.right])
+          end
+
+          super o, collector
+        end
+    end
+  end
+end

spec/active_record/oracle_enhanced/type/character_string_spec.rb

@@ -24,6 +24,7 @@ class ::TestItem < ActiveRecord::Base
   end
 
   after(:each) do
+    TestItem.delete_all
     Object.send(:remove_const, "TestItem")
     ActiveRecord::Base.clear_cache!
   end
@@ -40,4 +41,27 @@ class ::TestItem < ActiveRecord::Base
     item_reloaded = TestItem.first
     expect(item_reloaded.padded).to eq(str)
   end
+
+  it "should support case sensitive matching" do
+    TestItem.create!(
+      padded: "First",
+    )
+    TestItem.create!(
+      padded: "first",
+    )
+
+    expect(TestItem.where(TestItem.arel_table[:padded].matches("first%", "\\", true))).to have_attributes(count: 1)
+  end
+
+  it "should support case insensitive matching" do
+    TestItem.create!(
+      padded: "First",
+    )
+    TestItem.create!(
+      padded: "first",
+    )
+
+    expect(TestItem.where(TestItem.arel_table[:padded].matches("first%", "\\", false))).to have_attributes(count: 2)
+    expect(TestItem.where(TestItem.arel_table[:padded].matches("first%"))).to have_attributes(count: 2)
+  end
 end