Implement Twitter::Cursor#each without making an extra HTTP request

lib/twitter/api/friends_and_followers.rb

@@ -32,7 +32,7 @@ module FriendsAndFollowers
       #     Twitter.friend_ids('sferik')
       #     Twitter.friend_ids(7505382)  # Same as above
       def friend_ids(*args)
-        cursor_from_response_with_user(:ids, nil, :get, "/1.1/friends/ids.json", args, :friend_ids)
+        cursor_from_response_with_user(:ids, nil, :get, "/1.1/friends/ids.json", args)
       end
 
       # @see https://dev.twitter.com/docs/api/1.1/get/followers/ids
@@ -57,7 +57,7 @@ def friend_ids(*args)
       #     Twitter.follower_ids('sferik')
       #     Twitter.follower_ids(7505382)  # Same as above
       def follower_ids(*args)
-        cursor_from_response_with_user(:ids, nil, :get, "/1.1/followers/ids.json", args, :follower_ids)
+        cursor_from_response_with_user(:ids, nil, :get, "/1.1/followers/ids.json", args)
       end
 
       # Returns the relationship of the authenticating user to the comma separated list of up to 100 screen_names or user_ids provided. Values for connections can be: following, following_requested, followed_by, none.
@@ -94,7 +94,7 @@ def friendships(*args)
       # @example Return an array of numeric IDs for every user who has a pending request to follow the authenticating user
       #   Twitter.friendships_incoming
       def friendships_incoming(options={})
-        cursor_from_response(:ids, nil, :get, "/1.1/friendships/incoming.json", options, :friendships_incoming)
+        cursor_from_response(:ids, nil, :get, "/1.1/friendships/incoming.json", options)
       end
 
       # Returns an array of numeric IDs for every protected user for whom the authenticating user has a pending follow request
@@ -109,7 +109,7 @@ def friendships_incoming(options={})
       # @example Return an array of numeric IDs for every protected user for whom the authenticating user has a pending follow request
       #   Twitter.friendships_outgoing
       def friendships_outgoing(options={})
-        cursor_from_response(:ids, nil, :get, "/1.1/friendships/outgoing.json", options, :friendships_outgoing)
+        cursor_from_response(:ids, nil, :get, "/1.1/friendships/outgoing.json", options)
       end
 
       # Allows the authenticating user to follow the specified users, unless they are already followed
@@ -280,7 +280,7 @@ def friendship?(source, target, options={})
       #   Twitter.followers('sferik')
       #   Twitter.followers(7505382)    # Same as above
       def followers(*args)
-        cursor_from_response_with_user(:users, Twitter::User, :get, "/1.1/followers/list.json", args, :followers)
+        cursor_from_response_with_user(:users, Twitter::User, :get, "/1.1/followers/list.json", args)
       end
 
       # Returns a cursored collection of user objects for every user the specified user is following (otherwise known as their "friends").
@@ -311,7 +311,7 @@ def followers(*args)
       #   Twitter.friends('sferik')
       #   Twitter.friends(7505382)    # Same as above
       def friends(*args)
-        cursor_from_response_with_user(:users, Twitter::User, :get, "/1.1/friends/list.json", args, :friends)
+        cursor_from_response_with_user(:users, Twitter::User, :get, "/1.1/friends/list.json", args)
       end
       alias following friends
 

lib/twitter/api/lists.rb

@@ -125,7 +125,7 @@ def list_remove_member(*args)
       #     Twitter.memberships('sferik')
       #     Twitter.memberships(7505382)
       def memberships(*args)
-        cursor_from_response_with_user(:lists, Twitter::List, :get, "/1.1/lists/memberships.json", args, :memberships)
+        cursor_from_response_with_user(:lists, Twitter::List, :get, "/1.1/lists/memberships.json", args)
       end
 
       # Returns the subscribers of the specified list
@@ -152,7 +152,7 @@ def memberships(*args)
       #     Twitter.list_subscribers('sferik', 8863586)
       #     Twitter.list_subscribers(7505382, 'presidents')
       def list_subscribers(*args)
-        cursor_from_response_with_list(:get, "/1.1/lists/subscribers.json", args, :list_subscribers)
+        cursor_from_response_with_list(:get, "/1.1/lists/subscribers.json", args)
       end
 
       # Make the authenticated user follow the specified list
@@ -320,7 +320,7 @@ def list_member?(*args)
       #     Twitter.list_members(7505382, 'presidents')
       #     Twitter.list_members(7505382, 8863586)
       def list_members(*args)
-        cursor_from_response_with_list(:get, "/1.1/lists/members.json", args, :list_members)
+        cursor_from_response_with_list(:get, "/1.1/lists/members.json", args)
       end
 
       # Add a member to a list
@@ -474,7 +474,7 @@ def list(*args)
       #     Twitter.subscriptions('sferik')
       #     Twitter.subscriptions(7505382)
       def subscriptions(*args)
-        cursor_from_response_with_user(:lists, Twitter::List, :get, "/1.1/lists/subscriptions.json", args, :subscriptions)
+        cursor_from_response_with_user(:lists, Twitter::List, :get, "/1.1/lists/subscriptions.json", args)
       end
 
       # Removes specified members from the list
@@ -529,7 +529,7 @@ def list_remove_members(*args)
       #     Twitter.lists_owned('sferik')
       #     Twitter.lists_owned(7505382)
       def lists_owned(*args)
-        cursor_from_response_with_user(:lists, Twitter::List, :get, "/1.1/lists/ownerships.json", args, :lists_owned)
+        cursor_from_response_with_user(:lists, Twitter::List, :get, "/1.1/lists/ownerships.json", args)
       end
       alias lists_ownerships lists_owned
 
@@ -546,11 +546,11 @@ def list_from_response(request_method, path, args)
         object_from_response(Twitter::List, request_method, path, arguments.options)
       end
 
-      def cursor_from_response_with_list(request_method, path, args, calling_method)
+      def cursor_from_response_with_list(request_method, path, args)
         arguments = Twitter::API::Arguments.new(args)
         merge_list!(arguments.options, arguments.pop)
         merge_owner!(arguments.options, arguments.pop)
-        cursor_from_response(:users, Twitter::User, request_method, path, arguments.options, calling_method)
+        cursor_from_response(:users, Twitter::User, request_method, path, arguments.options)
       end
 
       def list_user?(request_method, path, args)

lib/twitter/api/tweets.rb

@@ -281,7 +281,7 @@ def oembeds(*args)
       def retweeters_ids(*args)
         arguments = Twitter::API::Arguments.new(args)
         arguments.options[:id] ||= extract_id(arguments.first)
-        cursor_from_response(:ids, nil, :get, "/1.1/statuses/retweeters/ids.json", arguments.options, :retweeters_ids)
+        cursor_from_response(:ids, nil, :get, "/1.1/statuses/retweeters/ids.json", arguments.options)
       end
 
     private

lib/twitter/api/undocumented.rb

@@ -35,7 +35,7 @@ module Undocumented
       #     Twitter.following_followers_of('sferik')
       #     Twitter.following_followers_of(7505382)  # Same as above
       def following_followers_of(*args)
-        cursor_from_response_with_user(:users, Twitter::User, :get, "/users/following_followers_of.json", args, :following_followers_of)
+        cursor_from_response_with_user(:users, Twitter::User, :get, "/users/following_followers_of.json", args)
       end
 
       # Returns Tweets count for a URL

lib/twitter/api/users.rb

@@ -153,7 +153,7 @@ def update_profile_image(image, options={})
       # @example Return an array of user objects that the authenticating user is blocking
       #   Twitter.blocking
       def blocking(options={})
-        cursor_from_response(:users, Twitter::User, :get, "/1.1/blocks/list.json", options, :blocking)
+        cursor_from_response(:users, Twitter::User, :get, "/1.1/blocks/list.json", options)
       end
 
       # Returns an array of numeric user ids the authenticating user is blocking
@@ -170,7 +170,7 @@ def blocking(options={})
       def blocked_ids(*args)
         arguments = Twitter::API::Arguments.new(args)
         merge_user!(arguments.options, arguments.pop)
-        cursor_from_response(:ids, nil, :get, "/1.1/blocks/ids.json", arguments.options, :blocked_ids)
+        cursor_from_response(:ids, nil, :get, "/1.1/blocks/ids.json", arguments.options)
       end
 
       # Returns true if the authenticating user is blocking a target user

lib/twitter/api/utils.rb

@@ -108,25 +108,23 @@ def object_from_response(klass, request_method, path, options={})
       # @param request_method [Symbol]
       # @param path [String]
       # @param args [Array]
-      # @param method_name [Symbol]
       # @return [Twitter::Cursor]
-      def cursor_from_response_with_user(collection_name, klass, request_method, path, args, method_name)
+      def cursor_from_response_with_user(collection_name, klass, request_method, path, args)
         arguments = Twitter::API::Arguments.new(args)
         merge_user!(arguments.options, arguments.pop || screen_name) unless arguments.options[:user_id] || arguments.options[:screen_name]
-        cursor_from_response(collection_name, klass, request_method, path, arguments.options, method_name)
+        cursor_from_response(collection_name, klass, request_method, path, arguments.options)
       end
 
       # @param collection_name [Symbol]
       # @param klass [Class]
       # @param request_method [Symbol]
       # @param path [String]
       # @param options [Hash]
-      # @param method_name [Symbol]
       # @return [Twitter::Cursor]
-      def cursor_from_response(collection_name, klass, request_method, path, options, method_name)
+      def cursor_from_response(collection_name, klass, request_method, path, options)
         merge_default_cursor!(options)
         response = send(request_method.to_sym, path, options)
-        Twitter::Cursor.from_response(response, collection_name.to_sym, klass, self, method_name, options)
+        Twitter::Cursor.from_response(response, collection_name.to_sym, klass, self, request_method, path, options)
       end
 
       def handle_forbidden_error(klass, error)

lib/twitter/cursor.rb

@@ -12,11 +12,12 @@ class Cursor
     # @param collection_name [String, Symbol] The name of the method to return the collection
     # @param klass [Class] The class to instantiate object in the collection
     # @param client [Twitter::Client]
-    # @param method_name [String, Symbol]
-    # @param method_options [Hash]
+    # @param request_method [String, Symbol]
+    # @param path [String]
+    # @param options [Hash]
     # @return [Twitter::Cursor]
-    def self.from_response(response, collection_name, klass, client, method_name, method_options)
-      new(response[:body], collection_name, klass, client, method_name, method_options)
+    def self.from_response(response, collection_name, klass, client, request_method, path, options)
+      new(response[:body], collection_name, klass, client, request_method, path, options)
     end
 
     # Initializes a new Cursor
@@ -25,40 +26,38 @@ def self.from_response(response, collection_name, klass, client, method_name, me
     # @param collection_name [String, Symbol] The name of the method to return the collection
     # @param klass [Class] The class to instantiate object in the collection
     # @param client [Twitter::Client]
-    # @param method_name [String, Symbol]
-    # @param method_options [Hash]
+    # @param request_method [String, Symbol]
+    # @param path [String]
+    # @param options [Hash]
     # @return [Twitter::Cursor]
-    def initialize(attrs, collection_name, klass, client, method_name, method_options)
-      @attrs = attrs
+    def initialize(attrs, collection_name, klass, client, request_method, path, options)
+      @collection_name = collection_name.to_sym
+      @klass = klass
       @client = client
-      @method_name = method_name
-      @method_options = method_options
-      @collection = Array(attrs[collection_name.to_sym]).map do |item|
-        if klass
-          klass.new(item)
-        else
-          item
-        end
-      end
+      @request_method = request_method.to_sym
+      @path = path
+      @options = options
+      set_attrs(attrs)
       singleton_class.class_eval do
         alias_method(collection_name.to_sym, :collection)
       end
     end
 
-    # @param collection [Array]
-    # @param cursor [Integer]
-    # @return [Array]
-    def all(collection=collection, cursor=next_cursor)
-      cursor = @client.send(@method_name.to_sym, @method_options.merge(:cursor => cursor))
-      collection += cursor.collection
-      cursor.last? ? collection.flatten : all(collection, cursor.next_cursor)
+    def all
+      map{|element| element}
     end
 
-    # @return [Enumerable]
-    def each
-      all(collection, next_cursor).each do |element|
+    # @return [Enumerator]
+    def each(&block)
+      return to_enum(:each) unless block_given?
+      @collection.each do |element|
         yield element
       end
+      unless last?
+        fetch_next
+        each(&block)
+      end
+      self
     end
 
     def next_cursor
@@ -75,13 +74,25 @@ def previous_cursor
     def first?
       previous_cursor.zero?
     end
-    alias first first?
 
     # @return [Boolean]
     def last?
       next_cursor.zero?
     end
-    alias last last?
+
+  private
+
+    def fetch_next
+      response = @client.send(@request_method, @path, @options.merge(:cursor => next_cursor))
+      set_attrs(response[:body])
+    end
+
+    def set_attrs(attrs)
+      @attrs = attrs
+      @collection = Array(attrs[@collection_name]).map do |element|
+        @klass ? @klass.new(element) : element
+      end
+    end
 
   end
 end

spec/twitter/cursor_spec.rb

@@ -4,7 +4,7 @@
 
   describe "#collection" do
     it "returns a collection" do
-      collection = Twitter::Cursor.new({:ids => [1, 2, 3, 4, 5]}, :ids, nil, Twitter::Client.new, :follower_ids, {}).collection
+      collection = Twitter::Cursor.new({:ids => [1, 2, 3, 4, 5]}, :ids, nil, Twitter::Client.new, :get, "/1.1/followers/ids.json", {}).collection
       expect(collection).to be_an Array
       expect(collection.first).to be_a Fixnum
     end
@@ -48,15 +48,15 @@
   describe "#first?" do
     context "when previous cursor equals zero" do
       before do
-        @cursor = Twitter::Cursor.new({:previous_cursor => 0}, :ids, nil, Twitter::Client.new, :follower_ids, {})
+        @cursor = Twitter::Cursor.new({:previous_cursor => 0}, :ids, nil, Twitter::Client.new, :get, "/1.1/followers/ids.json", {})
       end
       it "returns true" do
         expect(@cursor.first?).to be_true
       end
     end
     context "when previous cursor does not equal zero" do
       before do
-        @cursor = Twitter::Cursor.new({:previous_cursor => 1}, :ids, nil, Twitter::Client.new, :follower_ids, {})
+        @cursor = Twitter::Cursor.new({:previous_cursor => 1}, :ids, nil, Twitter::Client.new, :get, "/1.1/followers/ids.json", {})
       end
       it "returns true" do
         expect(@cursor.first?).to be_false
@@ -67,15 +67,15 @@
   describe "#last?" do
     context "when next cursor equals zero" do
       before do
-        @cursor = Twitter::Cursor.new({:next_cursor => 0}, :ids, nil, Twitter::Client.new, :follower_ids, {})
+        @cursor = Twitter::Cursor.new({:next_cursor => 0}, :ids, nil, Twitter::Client.new, :get, "/1.1/followers/ids.json", {})
       end
       it "returns true" do
         expect(@cursor.last?).to be_true
       end
     end
     context "when next cursor does not equal zero" do
       before do
-        @cursor = Twitter::Cursor.new({:next_cursor => 1}, :ids, nil, Twitter::Client.new, :follower_ids, {})
+        @cursor = Twitter::Cursor.new({:next_cursor => 1}, :ids, nil, Twitter::Client.new, :get, "/1.1/followers/ids.json", {})
       end
       it "returns false" do
         expect(@cursor.last?).to be_false