Hook mechanizm for route_added [help from rtomayko]

Example:

module Sinatra
  module RouteAddedExtSample
    def self.route_added(verb, path)
      p [verb, path]
    end
  end

  register RouteAddedExtSample
end

post '/' do
  do_something
  'ok'
end

Output:

["POST", "/"]

move superclass logic into extensions attr reader

lib/sinatra/base.rb

@@ -553,6 +553,7 @@ module Sinatra
     @middleware = []
     @errors     = {}
     @prototype  = nil
+    @extensions = []
 
     class << self
       attr_accessor :routes, :filters, :conditions, :templates,
@@ -698,10 +699,16 @@ module Sinatra
             lambda { unbound_method.bind(self).call }
           end
 
+        invoke_hook(:route_added, verb, path)
+
         (routes[verb] ||= []).
           push([pattern, keys, conditions, block]).last
       end
 
+      def invoke_hook(name, *args)
+        extensions.each { |e| e.send(name, *args) if e.respond_to?(name) }
+      end
+
       def compile(path)
         keys = []
         if path.respond_to? :to_str
@@ -733,8 +740,13 @@ module Sinatra
         include *extensions if extensions.any?
       end
 
+      def extensions
+        (@extensions + (superclass.extensions rescue [])).uniq
+      end
+
       def register(*extensions, &block)
         extensions << Module.new(&block) if block_given?
+        @extensions += extensions
         extensions.each do |extension|
           extend extension
           extension.registered(self) if extension.respond_to?(:registered)
@@ -817,6 +829,7 @@ module Sinatra
         @errors     = base.errors.dup
         @middleware = base.middleware.dup
         @prototype  = nil
+        @extensions = []
       end
 
     protected

test/route_added_hook_test.rb

@@ -0,0 +1,47 @@
+require File.dirname(__FILE__) + '/helper'
+
+module RouteAddedTest
+  @routes = []
+  def self.routes ; @routes ; end
+  def self.route_added(verb, path)
+    @routes << [verb, path]
+  end
+end
+
+describe "route_added Hook" do
+
+  before { RouteAddedTest.routes.clear }
+
+  it "should be notified of an added route" do
+    mock_app(Class.new(Sinatra::Base)) {
+      register RouteAddedTest
+      get('/') {}
+    }
+
+    assert_equal [["GET", "/"], ["HEAD", "/"]],
+      RouteAddedTest.routes
+  end
+
+  it "should include hooks from superclass" do
+    a = Class.new(Class.new(Sinatra::Base))
+    b = Class.new(a)
+
+    a.register RouteAddedTest
+    b.class_eval { post("/sub_app_route") {} }
+
+    assert_equal [["POST", "/sub_app_route"]],
+      RouteAddedTest.routes
+  end
+
+  it "should only run once per extension" do
+    mock_app(Class.new(Sinatra::Base)) {
+      register RouteAddedTest
+      register RouteAddedTest
+      get('/') {}
+    }
+
+    assert_equal [["GET", "/"], ["HEAD", "/"]],
+      RouteAddedTest.routes
+  end
+
+end