Lazy load type mappings

This appears to fix issue #2256. I believe it should have the same memory implications as the intention in #2199. The type maps are loaded once when they are first called. Only one instance of the mapping is ever created.

Fortunately this was enough to solve the problem, but if there were a need, this could easily be worked into the clear_cache! API to reset it at a later point in the application just by setting the @type_map to nil.

Author: andynu

lib/active_record/connection_adapters/oracle_enhanced_adapter.rb

@@ -459,6 +459,11 @@ def reconnect! # :nodoc:
         @logger.warn "#{adapter_name} automatic reconnection failed: #{e.message}" if @logger
       end
 
+      def clear_cache!
+        self.class.clear_type_map!
+        super
+      end
+
       def reset!
         clear_cache!
         super
@@ -697,6 +702,15 @@ def check_version
       end
 
       class << self
+        def type_map
+          @type_map ||= Type::TypeMap.new.tap { |m| initialize_type_map(m) }
+          @type_map
+        end
+
+        def clear_type_map!
+          @type_map = nil
+        end
+
         private
           def initialize_type_map(m)
             super
@@ -730,10 +744,8 @@ def initialize_type_map(m)
           end
       end
 
-      TYPE_MAP = Type::TypeMap.new.tap { |m| initialize_type_map(m) }
-
       def type_map
-        TYPE_MAP
+        self.class.type_map
       end
 
       def extract_value_from_default(default)

spec/active_record/oracle_enhanced/type/integer_spec.rb

@@ -87,5 +87,13 @@ class ::Test2Employee < ActiveRecord::Base
       create_employee2
       expect(@employee2.is_manager).to be_a(Integer)
     end
+
+    it "should return Integer value from NUMBER(1) column if emulate_booleans is set to false" do
+      ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.emulate_booleans = false
+      ActiveRecord::ConnectionAdapters::OracleEnhancedAdapter.clear_type_map!
+      ActiveRecord::Base.clear_cache!
+      create_employee2
+      expect(@employee2.is_manager).to be_a(Integer)
+    end
   end
 end