util.rb in instana-0.13.1

- old
+ new
@@ -1,52 +1,70 @@
 module Instana
   module Util
-    ##
-    # enforce_deltas
-    #
-    # Take two hashes, and make sure candidate does not have
-    # any of the same values as `last`.  We only report
-    # when values change.
-    #
-    # Note this is not recursive, so only pass in the single
-    # hashes that you want delta reporting with.
-    #
-    def self.enforce_deltas(candidate, last)
-      return unless last.is_a?(Hash)
+    class << self
+      # An agnostic approach to method aliasing.
+      #
+      # @param klass [Object] The class or module that holds the method to be alias'd.
+      # @param method [Symbol] The name of the method to be aliased.
+      #
+      def method_alias(klass, method)
+        if klass.method_defined?(method.to_sym)
 
-      candidate.each do |k,v|
-        if candidate[k] == last[k]
-          candidate.delete(k)
+          with = "#{method}_with_instana"
+          without = "#{method}_without_instana"
+
+          klass.class_eval do
+            alias_method without, method.to_s
+            alias_method method.to_s, with
+          end
+        else
+          ::Instana.logger.debug "No such method (#{method}) to alias on #{klass}"
         end
       end
-      candidate
-    end
-  end
 
-  ##
-  # Debugging helper method
-  #
-  def self.pry!
-    # Only valid for development or test environments
-    #env = ENV['RACK_ENV'] || ENV['RAILS_ENV']
-    #return unless %w(development, test).include? env
+      # Take two hashes, and make sure candidate does not have
+      # any of the same values as `last`.  We only report
+      # when values change.
+      #
+      # Note this is not recursive, so only pass in the single
+      # hashes that you want delta reporting with.
+      #
+      def enforce_deltas(candidate, last)
+        return unless last.is_a?(Hash)
 
-    if RUBY_VERSION > '1.8.7'
-      require 'pry-byebug'
+        candidate.each do |k,v|
+          if candidate[k] == last[k]
+            candidate.delete(k)
+          end
+        end
+        candidate
+      end
 
-      if defined?(PryByebug)
-        Pry.commands.alias_command 'c', 'continue'
-        Pry.commands.alias_command 's', 'step'
-        Pry.commands.alias_command 'n', 'next'
-        Pry.commands.alias_command 'f', 'finish'
+      # Debugging helper method
+      #
+      def pry!
+        # Only valid for development or test environments
+        #env = ENV['RACK_ENV'] || ENV['RAILS_ENV']
+        #return unless %w(development, test).include? env
 
-        Pry::Commands.command(/^$/, 'repeat last command') do
-          _pry_.run_command Pry.history.to_a.last
+        if RUBY_VERSION > '1.8.7'
+          require 'pry-byebug'
+
+          if defined?(PryByebug)
+            Pry.commands.alias_command 'c', 'continue'
+            Pry.commands.alias_command 's', 'step'
+            Pry.commands.alias_command 'n', 'next'
+            Pry.commands.alias_command 'f', 'finish'
+
+            Pry::Commands.command(/^$/, 'repeat last command') do
+              _pry_.run_command Pry.history.to_a.last
+            end
+          end
+
+          binding.pry
+        else
+          require 'ruby-debug'; debugger
         end
       end
-
-      binding.pry
-    else
-      require 'ruby-debug'; debugger
     end
   end
 end