lib/ddtrace/patcher.rb in ddtrace-0.12.0.beta2 vs lib/ddtrace/patcher.rb in ddtrace-0.12.0.rc1

@@ -1,18 +1,40 @@
 module Datadog
   # Defines some useful patching methods for integrations
   module Patcher
-    module_function
+    def self.included(base)
+      base.send(:extend, CommonMethods)
+      base.send(:include, CommonMethods)
+    end
 
-    def without_warnings
-      # This is typically used when monkey patching functions such as
-      # intialize, which Ruby advices you not to. Use cautiously.
-      v = $VERBOSE
-      $VERBOSE = nil
-      begin
-        yield
-      ensure
-        $VERBOSE = v
+    # Defines some common methods for patching, that can be used
+    # at the instance, class, or module level.
+    module CommonMethods
+      def without_warnings
+        # This is typically used when monkey patching functions such as
+        # intialize, which Ruby advices you not to. Use cautiously.
+        v = $VERBOSE
+        $VERBOSE = nil
+        begin
+          yield
+        ensure
+          $VERBOSE = v
+        end
       end
+
+      def do_once(key = nil)
+        # If already done, don't do again
+        @done_once ||= {}
+        return @done_once[key] if @done_once.key?(key)
+
+        # Otherwise 'do'
+        yield.tap do
+          # Then add the key so we don't do again.
+          @done_once[key] = true
+        end
+      end
     end
+
+    # Extend the common methods so they're available as a module function.
+    extend(CommonMethods)
   end
 end