1 files changed, 41 insertions, 0 deletions
diff --git a/storage/mroonga/vendor/groonga/lib/mrb/scripts/expression_rewriters.rb b/storage/mroonga/vendor/groonga/lib/mrb/scripts/expression_rewriters.rb
new file mode 100644
index 00000000..ae773541
--- /dev/null
+++ b/storage/mroonga/vendor/groonga/lib/mrb/scripts/expression_rewriters.rb
@@ -0,0 +1,41 @@
+module Groonga
+  module ExpressionRewriters
+    @rewriters = {}
+
+    class << self
+      def register(name, rewriter_class)
+        @rewriters[name] = rewriter_class
+      end
+
+      def enabled?
+        rewriters_table_name =
+          Config["expression_rewriter.table"] || "expression_rewriters"
+        rewriters_table = Context.instance[rewriters_table_name]
+        return false if rewriters_table.nil?
+        return false if rewriters_table.empty?
+
+        true
+      end
+
+      def classes
+        rewriters_table_name =
+          Config["expression_rewriter.table"] || "expression_rewriters"
+        rewriters_table = Context.instance[rewriters_table_name]
+        return [] if rewriters_table.nil?
+
+        rewriters_table.collect do |id|
+          record = Record.new(rewriters_table, id)
+          name = record.key
+          rewriter = @rewriters[name]
+          if rewriter.nil?
+            plugin_name = record.plugin_name.value
+            require plugin_name
+            rewriter = @rewriters[name]
+            raise "unknown rewriter: <#{name}>:<#{plugin_name}>" if rewriter.nil?
+          end
+          rewriter
+        end
+      end
+    end
+  end
+end