diff --git a/app/models/pending_post.rb b/app/models/pending_post.rb
deleted file mode 100644
index 20c17820e..000000000
--- a/app/models/pending_post.rb
+++ /dev/null
@@ -1,210 +0,0 @@
-require "danbooru_image_resizer/danbooru_image_resizer"
-require "tmpdir"
-
-class PendingPost < ActiveRecord::Base
-  attr_accessor :file, :image_width, :image_height, :file_ext, :md5, :file_size
-  belongs_to :uploader, :class_name => "User"
-  before_save :convert_cgi_file
-  
-  def process!
-    update_attribute(:status, "processing")
-    if is_downloadable?
-      download_from_source(temp_file_path)
-    end
-    self.file_ext = content_type_to_file_ext(content_type)
-    calculate_hash(file_path)
-    calculate_file_size(file_path)
-    calculate_dimensions(file_path) if has_dimensions?
-    generate_resizes(file_path)
-    move_file
-    post = convert_to_post
-    if post.save
-      update_attributes(:status => "finished", :post_id => post.id)
-    else
-      update_attribute(:status, "error: " + post.errors.full_messages.join(", "))
-    end
-  end
-
-  def convert_to_post
-    returning Post.new do |p|
-      p.tag_string = tag_string
-      p.md5 = md5
-      p.file_ext = file_ext
-      p.image_width = image_width
-      p.image_height = image_height
-      p.uploader_id = uploader_id
-      p.uploader_ip_addr = uploader_ip_addr
-      p.updater_id = uploader_id
-      p.updater_ip_addr = uploader_ip_addr
-      p.rating = rating
-      p.source = source
-      p.file_size = file_size      
-    end
-  end
-  
-  def move_file
-    FileUtils.mv(file_path, md5_file_path)
-  end
-  
-  def calculate_file_size(source_path)
-    self.file_size = File.size(source_path)
-  end
-  
-  # Calculates the MD5 based on whatever is in temp_file_path
-  def calculate_hash(source_path)
-    self.md5 = Digest::MD5.file(source_path).hexdigest
-  end
-
-  class Error < Exception ; end
-  
-  module ResizerMethods
-    def generate_resizes(source_path)
-      generate_resize_for(Danbooru.config.small_image_width, Danbooru.config.small_image_width, source_path)
-      generate_resize_for(Danbooru.config.medium_image_width, nil, source_path)
-      generate_resize_for(Danbooru.config.large_image_width, nil, source_path)
-    end
-
-    def generate_resize_for(width, height, source_path)
-      return if width.nil?
-      return unless image_width > width
-      return unless height.nil? || image_height > height
-
-      unless File.exists?(source_path)
-        raise Error.new("file not found")
-      end
-
-      size = Danbooru.reduce_to({:width => image_width, :height => image_height}, {:width => width, :height => height})
-
-      # If we're not reducing the resolution, only reencode if the source image larger than
-      # 200 kilobytes.
-      if size[:width] == image_width && size[:height] == image_height && File.size?(source_path) < 200.kilobytes
-        return
-      end
-
-      Danbooru.resize(file_ext, source_path, resized_file_path_for(width), size, 90)
-    end
-  end
-
-  module DimensionMethods
-    # Figures out the dimensions of the image.
-    def calculate_dimensions(file_path)
-      image_size = ImageSize.new(File.open(file_path, "rb"))
-      self.image_width = image_size.get_width
-      self.image_height = image_size.get_height
-    end
-
-    # Does this file have image dimensions?
-    def has_dimensions?
-      %w(jpg gif png swf).include?(file_ext)
-    end
-  end
-  
-  module ContentTypeMethods
-    def content_type_to_file_ext(content_type)
-      case content_type
-      when "image/jpeg"
-        "jpg"
-        
-      when "image/gif"
-        "gif"
-        
-      when "image/png"
-        "png"
-        
-      when "application/x-shockwave-flash"
-        "swf"
-        
-      else
-        "bin"
-      end
-    end
-    
-    # Converts a content type string to a file extension
-    def file_ext_to_content_type(file_ext)
-      case file_ext
-      when /\.jpeg$|\.jpg$/
-        "image/jpeg"
-
-      when /\.gif$/
-        "image/gif"
-
-      when /\.png$/
-        "image/png"
-
-      when /\.swf$/
-        "application/x-shockwave-flash"
-
-      else
-        "application/octet-stream"
-      end
-    end
-  end
-
-  module FilePathMethods
-    def md5_file_path
-      prefix = Rails.env == "test" ? "test." : ""
-      "#{Rails.root}/public/data/original/#{prefix}#{md5}.#{file_ext}"
-    end
-    
-    def resized_file_path_for(width)
-      prefix = Rails.env == "test" ? "test." : ""
-
-      case width
-      when Danbooru.config.small_image_width
-        "#{Rails.root}/public/data/thumb/#{prefix}#{md5}.jpg"
-
-      when Danbooru.config.medium_image_width
-        "#{Rails.root}/public/data/medium/#{prefix}#{md5}.jpg"
-
-      when Danbooru.config.large_image_width
-        "#{Rails.root}/public/data/large/#{prefix}#{md5}.jpg"
-      end
-    end
-    
-    def temp_file_path
-      File.join(Dir::tmpdir, "#{Time.now.to_f}.#{$PROCESS_ID}")
-    end
-  end
-  
-  module DownloaderMethods
-    # Determines whether the source is downloadable
-    def is_downloadable?
-      source =~ /^http:\/\// && file_path.blank?
-    end
-
-    # Downloads the file to destination_path
-    def download_from_source(destination_path)
-      download = Download.new(source, destination_path)
-      download.download!
-      self.file_path = destination_path
-      self.content_type = download.content_type || file_ext_to_content_type(source)
-      self.file_ext = content_type_to_file_ext(content_type)
-      self.source = download.source
-    end
-  end
-
-  module CgiFileMethods
-    def convert_cgi_file
-      return if file.blank? || file.size == 0
-
-      if file.local_path
-        self.file_path = file.local_path
-      else
-        self.file_path = temp_file_path
-        
-        File.open(file_path, 'wb') do |out| 
-          out.write(file.read)
-        end
-      end
-      self.content_type = file.content_type || file_ext_to_content_type(file.original_filename)
-      self.file_ext = content_type_to_file_ext(content_type)
-    end
-  end
-  
-  include ResizerMethods
-  include DimensionMethods
-  include ContentTypeMethods
-  include DownloaderMethods
-  include FilePathMethods
-  include CgiFileMethods
-end
\ No newline at end of file
diff --git a/app/models/tag_alias.rb b/app/models/tag_alias.rb
index fee5ab714..ea69ba203 100644
--- a/app/models/tag_alias.rb
+++ b/app/models/tag_alias.rb
@@ -1,9 +1,10 @@
 class TagAlias < ActiveRecord::Base
   attr_accessor :updater_id, :updater_ip_addr
   after_save :update_posts
-  after_save :update_cache
+  after_destroy :clear_cache
   validates_presence_of :updater_id, :updater_ip_addr
   validates_uniqueness_of :antecedent_name
+  validate :absence_of_transitive_relation
   belongs_to :updater, :class_name => "User"
   belongs_to :creator, :class_name => "User"
   
@@ -20,8 +21,20 @@ class TagAlias < ActiveRecord::Base
     alias_hash.values.uniq
   end
   
+  def absence_of_transitive_relation
+    # We don't want a -> b && b -> c chains
+    if self.class.exists?(["antecedent_name = ?", consequent_name]) || self.class.exists?(["consequent_name = ?", antecedent_name])
+      self.errors[:base] << "Tag alias can not create a transitive relation with another tag alias"
+      false
+    end
+  end
+
+  def clear_cache
+    Cache.delete("ta:#{Cache.sanitize(antecedent_name)}")
+  end
+  
   def update_cache
-    Cache.put("ta:#{Cache.sanitize(antecedent_name)}", consequent_name, 24.hours)
+    Cache.put("ta:#{Cache.sanitize(antecedent_name)}", consequent_name)
   end
   
   def update_posts
diff --git a/app/models/tag_implication.rb b/app/models/tag_implication.rb
index 8e447b727..633062f7c 100644
--- a/app/models/tag_implication.rb
+++ b/app/models/tag_implication.rb
@@ -1,32 +1,82 @@
 class TagImplication < ActiveRecord::Base
-  after_save :update_descendant_names
+  attr_accessor :updater_id, :updater_ip_addr
+  before_save :update_descendant_names
+  after_save :update_descendant_names_for_parent
+  after_save :clear_cache
+  after_destroy :clear_cache
+  after_save :update_posts
+  belongs_to :creator, :class_name => "User"
+  belongs_to :updater, :class_name => "User"
+  validates_presence_of :updater_id, :updater_ip_addr, :creator_id
   
   def self.with_descendants(names)
     names.map do |name|
-      ti = TagImplication.find_by_antecedent_name(name)
+      ti = find_by_antecedent_name(name)
       if ti
-        [name, ti.descendant_name_array]
+        [name, ti.descendant_names_array]
       else
         name
       end
     end.flatten
   end
   
+  def parent
+    @parent ||= self.class.where(["consequent_name = ?", antecedent_name]).first
+  end
+  
   def descendants
     all = []
     children = [consequent_name]
     
     until children.empty?
       all += children
-      children = where(["antecedent_name IN (?)", children]).all.map(&:consequent_name)
+      children = self.class.where(["antecedent_name IN (?)", children]).all.map(&:consequent_name)
+    end
+    
+    all
+  end
+  
+  def descendant_names_array
+    Cache.get("ti:#{Cache.sanitize(antecedent_name)}") do
+      descendant_names.split(/ /)
     end
   end
   
-  def descendant_name_array
-    descendant_names.split(/ /)
-  end
-  
-  def update_desecendant_names
+  def update_descendant_names
     self.descendant_names = descendants.join(" ")
   end
+  
+  def update_descendant_names!
+    update_descendant_names
+    save
+  end
+  
+  def update_descendant_names_for_parent
+    parent.update_descendant_names! if parent
+  end
+
+  def clear_cache
+    Cache.delete("ti:#{Cache.sanitize(antecedent_name)}")
+  end
+  
+  def update_posts
+    Post.find_by_tags(antecedent_name).find_each do |post|
+      escaped_antecedent_name = Regexp.escape(antecedent_name)
+      fixed_tags = post.tag_string.sub(/\A#{escaped_antecedent_name} | #{escaped_antecedent_name} | #{escaped_antecedent_name}\Z/, " #{descendant_names} ").strip
+      post.update_attributes(
+        :tag_string => fixed_tags,
+        :updater_id => updater_id,
+        :updater_ip_addr => updater_ip_addr
+      )
+    end
+  end
+  
+  def reload(options = {})
+    super
+    clear_parent_cache
+  end
+  
+  def clear_parent_cache
+    @parent = nil
+  end
 end
diff --git a/db/development_structure.sql b/db/development_structure.sql
index f0fcacddd..218e63177 100644
--- a/db/development_structure.sql
+++ b/db/development_structure.sql
@@ -374,45 +374,6 @@ CREATE SEQUENCE favorites_9_id_seq
 ALTER SEQUENCE favorites_9_id_seq OWNED BY favorites_9.id;
 
 
---
--- Name: pending_posts; Type: TABLE; Schema: public; Owner: -; Tablespace: 
---
-
-CREATE TABLE pending_posts (
-    id integer NOT NULL,
-    created_at timestamp without time zone,
-    updated_at timestamp without time zone,
-    source character varying(255),
-    file_path character varying(255),
-    content_type character varying(255),
-    rating character(1) NOT NULL,
-    uploader_id integer NOT NULL,
-    uploader_ip_addr inet NOT NULL,
-    tag_string text NOT NULL,
-    status character varying(255) DEFAULT 'pending'::character varying NOT NULL,
-    post_id integer
-);
-
-
---
--- Name: pending_posts_id_seq; Type: SEQUENCE; Schema: public; Owner: -
---
-
-CREATE SEQUENCE pending_posts_id_seq
-    START WITH 1
-    INCREMENT BY 1
-    NO MAXVALUE
-    NO MINVALUE
-    CACHE 1;
-
-
---
--- Name: pending_posts_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
---
-
-ALTER SEQUENCE pending_posts_id_seq OWNED BY pending_posts.id;
-
-
 --
 -- Name: pool_versions; Type: TABLE; Schema: public; Owner: -; Tablespace: 
 --
@@ -724,6 +685,45 @@ CREATE SEQUENCE unapprovals_id_seq
 ALTER SEQUENCE unapprovals_id_seq OWNED BY unapprovals.id;
 
 
+--
+-- Name: uploads; Type: TABLE; Schema: public; Owner: -; Tablespace: 
+--
+
+CREATE TABLE uploads (
+    id integer NOT NULL,
+    created_at timestamp without time zone,
+    updated_at timestamp without time zone,
+    source character varying(255),
+    file_path character varying(255),
+    content_type character varying(255),
+    rating character(1) NOT NULL,
+    uploader_id integer NOT NULL,
+    uploader_ip_addr inet NOT NULL,
+    tag_string text NOT NULL,
+    status character varying(255) DEFAULT 'pending'::character varying NOT NULL,
+    post_id integer
+);
+
+
+--
+-- Name: uploads_id_seq; Type: SEQUENCE; Schema: public; Owner: -
+--
+
+CREATE SEQUENCE uploads_id_seq
+    START WITH 1
+    INCREMENT BY 1
+    NO MAXVALUE
+    NO MINVALUE
+    CACHE 1;
+
+
+--
+-- Name: uploads_id_seq; Type: SEQUENCE OWNED BY; Schema: public; Owner: -
+--
+
+ALTER SEQUENCE uploads_id_seq OWNED BY uploads.id;
+
+
 --
 -- Name: users; Type: TABLE; Schema: public; Owner: -; Tablespace: 
 --
@@ -843,13 +843,6 @@ ALTER TABLE favorites_8 ALTER COLUMN id SET DEFAULT nextval('favorites_8_id_seq'
 ALTER TABLE favorites_9 ALTER COLUMN id SET DEFAULT nextval('favorites_9_id_seq'::regclass);
 
 
---
--- Name: id; Type: DEFAULT; Schema: public; Owner: -
---
-
-ALTER TABLE pending_posts ALTER COLUMN id SET DEFAULT nextval('pending_posts_id_seq'::regclass);
-
-
 --
 -- Name: id; Type: DEFAULT; Schema: public; Owner: -
 --
@@ -906,6 +899,13 @@ ALTER TABLE tags ALTER COLUMN id SET DEFAULT nextval('tags_id_seq'::regclass);
 ALTER TABLE unapprovals ALTER COLUMN id SET DEFAULT nextval('unapprovals_id_seq'::regclass);
 
 
+--
+-- Name: id; Type: DEFAULT; Schema: public; Owner: -
+--
+
+ALTER TABLE uploads ALTER COLUMN id SET DEFAULT nextval('uploads_id_seq'::regclass);
+
+
 --
 -- Name: id; Type: DEFAULT; Schema: public; Owner: -
 --
@@ -993,14 +993,6 @@ ALTER TABLE ONLY favorites_9
     ADD CONSTRAINT favorites_9_pkey PRIMARY KEY (id);
 
 
---
--- Name: pending_posts_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
---
-
-ALTER TABLE ONLY pending_posts
-    ADD CONSTRAINT pending_posts_pkey PRIMARY KEY (id);
-
-
 --
 -- Name: pool_versions_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
 --
@@ -1065,6 +1057,14 @@ ALTER TABLE ONLY unapprovals
     ADD CONSTRAINT unapprovals_pkey PRIMARY KEY (id);
 
 
+--
+-- Name: uploads_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
+--
+
+ALTER TABLE ONLY uploads
+    ADD CONSTRAINT uploads_pkey PRIMARY KEY (id);
+
+
 --
 -- Name: users_pkey; Type: CONSTRAINT; Schema: public; Owner: -; Tablespace: 
 --
diff --git a/db/migrate/20100205224030_create_pending_posts.rb b/db/migrate/20100205224030_create_pending_posts.rb
deleted file mode 100644
index 5aac1e159..000000000
--- a/db/migrate/20100205224030_create_pending_posts.rb
+++ /dev/null
@@ -1,21 +0,0 @@
-class CreatePendingPosts < ActiveRecord::Migration
-  def self.up
-    create_table :pending_posts do |t|
-      t.timestamps
-      t.column :source, :string
-      t.column :file_path, :string
-      t.column :content_type, :string
-      
-      t.column :rating, :character, :null => false
-      t.column :uploader_id, :integer, :null => false
-      t.column :uploader_ip_addr, "inet", :null => false
-      t.column :tag_string, :text, :null => false
-      t.column :status, :string, :null => false, :default => "pending"
-      t.column :post_id, :integer
-    end
-  end
-
-  def self.down
-    drop_table :pending_posts
-  end
-end
diff --git a/db/migrate/20100211191709_create_tag_aliases.rb b/db/migrate/20100211191709_create_tag_aliases.rb
index 9c025aa93..eb3aac2c3 100644
--- a/db/migrate/20100211191709_create_tag_aliases.rb
+++ b/db/migrate/20100211191709_create_tag_aliases.rb
@@ -9,6 +9,7 @@ class CreateTagAliases < ActiveRecord::Migration
     end
     
     add_index :tag_aliases, :antecedent_name
+    add_index :tag_aliases, :consequent_name
   end
 
   def self.down
diff --git a/db/migrate/20100211191716_create_tag_implications.rb b/db/migrate/20100211191716_create_tag_implications.rb
index 3078f9728..9d2f2eb75 100644
--- a/db/migrate/20100211191716_create_tag_implications.rb
+++ b/db/migrate/20100211191716_create_tag_implications.rb
@@ -10,6 +10,7 @@ class CreateTagImplications < ActiveRecord::Migration
     end
     
     add_index :tag_implications, :antecedent_name
+    add_index :tag_implications, :consequent_name
   end
 
   def self.down
diff --git a/lib/cache.rb b/lib/cache.rb
index 3f31c94e4..fd29ea27e 100644
--- a/lib/cache.rb
+++ b/lib/cache.rb
@@ -25,7 +25,9 @@ module Cache
       hash[x] = "#{prefix}:#{Cache.sanitize(x)}"
       hash
     end
+    start_time = Time.now
     sanitized_key_to_value_hash = MEMCACHE.get_multi(key_to_sanitized_key_hash.values)
+    elapsed = Time.now - start_time
     returning({}) do |result_hash|
       key_to_sanitized_key_hash.each do |key, sanitized_key|
         if sanitized_key_to_value_hash.has_key?(sanitized_key)
@@ -35,16 +37,12 @@ module Cache
           Cache.put(sanitized_key, result_hash[key], expiry)
         end
       end
+      
+      ActiveRecord::Base.logger.debug('MemCache Multi-Get (%0.6f)  %s' % [elapsed, keys.join(",")])
     end
   end
   
   def get(key, expiry = 0)
-    if block_given?
-      return yield
-    else
-      return nil
-    end
-    
     begin
       start_time = Time.now
       value = MEMCACHE.get key
diff --git a/test/factories/pending_post.rb b/test/factories/pending_post.rb
deleted file mode 100644
index 34272f706..000000000
--- a/test/factories/pending_post.rb
+++ /dev/null
@@ -1,43 +0,0 @@
-require 'fileutils'
-
-Factory.define(:pending_post) do |f|
-  f.rating "s"
-  f.uploader {|x| x.association(:user)}
-  f.uploader_ip_addr "127.0.0.1"
-  f.tag_string "special"
-  f.status "pending"
-end
-
-Factory.define(:downloadable_pending_post, :parent => :pending_post) do |f|
-  f.source "http://www.google.com/intl/en_ALL/images/logo.gif"
-end
-
-Factory.define(:uploaded_jpg_pending_post, :parent => :pending_post) do |f|
-  f.file_path do
-    FileUtils.cp("#{Rails.root}/test/files/test.jpg", "#{Rails.root}/tmp")
-    "#{Rails.root}/tmp/test.jpg"
-  end
-end
-
-Factory.define(:uploaded_large_jpg_pending_post, :parent => :pending_post) do |f|
-  f.file_ext "jpg"
-  f.content_type "image/jpeg"
-  f.file_path do
-    FileUtils.cp("#{Rails.root}/test/files/test-large.jpg", "#{Rails.root}/tmp")
-    "#{Rails.root}/tmp/test-large.jpg"
-  end
-end
-
-Factory.define(:uploaded_png_pending_post, :parent => :pending_post) do |f|
-  f.file_path do
-    FileUtils.cp("#{Rails.root}/test/files/test.png", "#{Rails.root}/tmp")
-    "#{Rails.root}/tmp/test.png"
-  end
-end
-
-Factory.define(:uploaded_gif_pending_post, :parent => :pending_post) do |f|
-  f.file_path do
-    FileUtils.cp("#{Rails.root}/test/files/test.gif", "#{Rails.root}/tmp")
-    "#{Rails.root}/tmp/test.gif"
-  end
-end
diff --git a/test/factories/tag_implication.rb b/test/factories/tag_implication.rb
new file mode 100644
index 000000000..80d2357ae
--- /dev/null
+++ b/test/factories/tag_implication.rb
@@ -0,0 +1,5 @@
+Factory.define(:tag_implication) do |f|
+  f.creator {|x| x.association(:user)}
+  f.updater_id {|x| x.creator_id}
+  f.updater_ip_addr "127.0.0.1"
+end
diff --git a/test/factories/upload.rb b/test/factories/upload.rb
index d4eaa56f6..e6f1929c4 100644
--- a/test/factories/upload.rb
+++ b/test/factories/upload.rb
@@ -8,18 +8,18 @@ Factory.define(:upload) do |f|
   f.status "pending"
 end
 
-Factory.define(:downloadable_upload, :parent => :upload) do |f|
+Factory.define(:source_upload, :parent => :upload) do |f|
   f.source "http://www.google.com/intl/en_ALL/images/logo.gif"
 end
 
-Factory.define(:uploaded_jpg_upload, :parent => :upload) do |f|
+Factory.define(:jpg_upload, :parent => :upload) do |f|
   f.file_path do
     FileUtils.cp("#{Rails.root}/test/files/test.jpg", "#{Rails.root}/tmp")
     "#{Rails.root}/tmp/test.jpg"
   end
 end
 
-Factory.define(:uploaded_large_jpg_upload, :parent => :upload) do |f|
+Factory.define(:large_jpg_upload, :parent => :upload) do |f|
   f.file_ext "jpg"
   f.content_type "image/jpeg"
   f.file_path do
@@ -28,14 +28,14 @@ Factory.define(:uploaded_large_jpg_upload, :parent => :upload) do |f|
   end
 end
 
-Factory.define(:uploaded_png_upload, :parent => :upload) do |f|
+Factory.define(:png_upload, :parent => :upload) do |f|
   f.file_path do
     FileUtils.cp("#{Rails.root}/test/files/test.png", "#{Rails.root}/tmp")
     "#{Rails.root}/tmp/test.png"
   end
 end
 
-Factory.define(:uploaded_gif_upload, :parent => :upload) do |f|
+Factory.define(:gif_upload, :parent => :upload) do |f|
   f.file_path do
     FileUtils.cp("#{Rails.root}/test/files/test.gif", "#{Rails.root}/tmp")
     "#{Rails.root}/tmp/test.gif"
diff --git a/test/unit/pending_post_test.rb b/test/unit/pending_post_test.rb
deleted file mode 100644
index 7b3ab866e..000000000
--- a/test/unit/pending_post_test.rb
+++ /dev/null
@@ -1,156 +0,0 @@
-require File.dirname(__FILE__) + '/../test_helper'
-
-class PendingPostTest < ActiveSupport::TestCase
-  context "A pending post" do    
-    teardown do
-      FileUtils.rm_f(Dir.glob("#{Rails.root}/tmp/test.*"))
-    end
-
-    context "image size calculator" do
-      should "discover the dimensions for a JPG" do
-        @pending_post = Factory.create(:uploaded_jpg_pending_post)
-        assert_nothing_raised {@pending_post.calculate_dimensions(@pending_post.file_path)}
-        assert_equal(500, @pending_post.image_width)
-        assert_equal(335, @pending_post.image_height)
-      end
-
-      should "discover the dimensions for a PNG" do
-        @pending_post = Factory.create(:uploaded_png_pending_post)
-        assert_nothing_raised {@pending_post.calculate_dimensions(@pending_post.file_path)}
-        assert_equal(768, @pending_post.image_width)
-        assert_equal(1024, @pending_post.image_height)
-      end
-
-      should "discover the dimensions for a GIF" do
-        @pending_post = Factory.create(:uploaded_gif_pending_post)
-        assert_nothing_raised {@pending_post.calculate_dimensions(@pending_post.file_path)}
-        assert_equal(400, @pending_post.image_width)
-        assert_equal(400, @pending_post.image_height)
-      end
-    end
-    
-    context "content type calculator" do
-      should "know how to parse jpeg, png, gif, and swf file extensions" do
-        @pending_post = Factory.create(:uploaded_jpg_pending_post)
-        assert_equal("image/jpeg", @pending_post.file_ext_to_content_type("test.jpeg"))
-        assert_equal("image/gif", @pending_post.file_ext_to_content_type("test.gif"))
-        assert_equal("image/png", @pending_post.file_ext_to_content_type("test.png"))
-        assert_equal("application/x-shockwave-flash", @pending_post.file_ext_to_content_type("test.swf"))
-        assert_equal("application/octet-stream", @pending_post.file_ext_to_content_type(""))
-      end
-
-      should "know how to parse jpeg, png, gif, and swf content types" do
-        @pending_post = Factory.create(:uploaded_jpg_pending_post)
-        assert_equal("jpg", @pending_post.content_type_to_file_ext("image/jpeg"))
-        assert_equal("gif", @pending_post.content_type_to_file_ext("image/gif"))
-        assert_equal("png", @pending_post.content_type_to_file_ext("image/png"))
-        assert_equal("swf", @pending_post.content_type_to_file_ext("application/x-shockwave-flash"))
-        assert_equal("bin", @pending_post.content_type_to_file_ext(""))
-      end
-    end
-    
-    context "downloader" do
-      should "initialize the final path and content type after downloading a file" do
-        @pending_post = Factory.create(:downloadable_pending_post)
-        path = "#{Rails.root}/tmp/test.download.jpg"
-        assert_nothing_raised {@pending_post.download_from_source(path)}
-        assert(File.exists?(path))
-        assert_equal(8558, File.size(path))
-        assert_equal("image/gif", @pending_post.content_type)
-        assert_equal(path, @pending_post.file_path)
-        assert_equal("gif", @pending_post.file_ext)
-      end
-    end
-    
-    context "file processor" do
-      should "parse and process a cgi file representation" do
-        FileUtils.cp("#{Rails.root}/test/files/test.jpg", "#{Rails.root}/tmp")
-        @pending_post = PendingPost.new(:file => upload_jpeg("#{Rails.root}/tmp/test.jpg"))
-        assert_nothing_raised {@pending_post.convert_cgi_file}
-        assert_equal("image/jpeg", @pending_post.content_type)
-        assert(File.exists?(@pending_post.file_path))
-        assert_equal(28086, File.size(@pending_post.file_path))
-        assert_equal("jpg", @pending_post.file_ext)
-      end
-    end
-
-    context "hash calculator" do
-      should "caculate the hash" do
-        @pending_post = Factory.create(:uploaded_jpg_pending_post)
-        @pending_post.calculate_hash(@pending_post.file_path)
-        assert_equal("ecef68c44edb8a0d6a3070b5f8e8ee76", @pending_post.md5)
-      end
-    end
-    
-    context "resizer" do
-      teardown do
-        FileUtils.rm_f(Dir.glob("#{Rails.root}/public/data/thumb/test.*.jpg"))
-        FileUtils.rm_f(Dir.glob("#{Rails.root}/public/data/medium/test.*.jpg"))
-        FileUtils.rm_f(Dir.glob("#{Rails.root}/public/data/large/test.*.jpg"))
-        FileUtils.rm_f(Dir.glob("#{Rails.root}/public/data/original/test.*.jpg"))
-      end
-      
-      should "generate several resized versions of the image" do
-        @pending_post = Factory.create(:uploaded_large_jpg_pending_post)
-        @pending_post.calculate_hash(@pending_post.file_path)
-        @pending_post.calculate_dimensions(@pending_post.file_path)
-        assert_nothing_raised {@pending_post.generate_resizes(@pending_post.file_path)}
-        assert(File.exists?(@pending_post.resized_file_path_for(Danbooru.config.small_image_width)))
-        assert_equal(6556, File.size(@pending_post.resized_file_path_for(Danbooru.config.small_image_width)))
-        assert(File.exists?(@pending_post.resized_file_path_for(Danbooru.config.medium_image_width)))
-        assert_equal(39411, File.size(@pending_post.resized_file_path_for(Danbooru.config.medium_image_width)))
-        assert(File.exists?(@pending_post.resized_file_path_for(Danbooru.config.large_image_width)))
-        assert_equal(179324, File.size(@pending_post.resized_file_path_for(Danbooru.config.large_image_width)))
-      end
-    end
-    
-    should "process completely for a downloaded image" do
-      @pending_post = Factory.create(:downloadable_pending_post,
-        :rating => "s",
-        :uploader_ip_addr => "127.0.0.1",
-        :tag_string => "hoge foo"
-      )
-      assert_difference("Post.count") do
-        assert_nothing_raised {@pending_post.process!}
-      end
-      
-      post = Post.last
-      assert_equal("hoge foo", post.tag_string)
-      assert_equal("s", post.rating)
-      assert_equal(@pending_post.uploader_id, post.uploader_id)
-      assert_equal("127.0.0.1", post.uploader_ip_addr)
-      assert_equal(@pending_post.md5, post.md5)
-      assert_equal("gif", post.file_ext)
-      assert_equal(276, post.image_width)
-      assert_equal(110, post.image_height)
-      assert_equal(8558, post.file_size)
-      assert_equal(post.id, @pending_post.post_id)
-      assert_equal("finished", @pending_post.status)
-    end
-  end
-  
-  should "process completely for an uploaded image" do
-    @pending_post = Factory.create(:uploaded_jpg_pending_post,
-      :rating => "s",
-      :uploader_ip_addr => "127.0.0.1",
-      :tag_string => "hoge foo"
-    )
-    @pending_post.file = upload_jpeg("#{Rails.root}/test/files/test.jpg")
-    @pending_post.convert_cgi_file
-
-    assert_difference("Post.count") do
-      assert_nothing_raised {@pending_post.process!}
-    end
-    post = Post.last
-    assert_equal("hoge foo", post.tag_string)
-    assert_equal("s", post.rating)
-    assert_equal(@pending_post.uploader_id, post.uploader_id)
-    assert_equal("127.0.0.1", post.uploader_ip_addr)
-    assert_equal(@pending_post.md5, post.md5)
-    assert_equal("jpg", post.file_ext)
-    assert(File.exists?(post.file_path))
-    assert_equal(28086, File.size(post.file_path))
-    assert_equal(post.id, @pending_post.post_id)
-    assert_equal("finished", @pending_post.status)    
-  end
-end
diff --git a/test/unit/tag_alias_test.rb b/test/unit/tag_alias_test.rb
index 1fb99da6f..f8ecab769 100644
--- a/test/unit/tag_alias_test.rb
+++ b/test/unit/tag_alias_test.rb
@@ -19,6 +19,8 @@ class TagAliasTest < ActiveSupport::TestCase
       tag2 = Factory.create(:tag, :name => "bbb")
       ta = Factory.create(:tag_alias, :antecedent_name => "aaa", :consequent_name => "bbb")
       assert_equal("bbb", MEMCACHE.get("ta:aaa"))
+      ta.destroy
+      assert_nil(MEMCACHE.get("ta:aaa"))
     end
     
     should "update any affected posts when saved" do
@@ -33,5 +35,14 @@ class TagAliasTest < ActiveSupport::TestCase
       assert_equal("ccc bbb", post1.tag_string)
       assert_equal("ccc ddd", post2.tag_string)
     end
+    
+    should "not validate for transitive relations" do
+      ta1 = Factory.create(:tag_alias, :antecedent_name => "aaa", :consequent_name => "bbb")
+      assert_difference("TagAlias.count", 0) do
+        ta3 = TagAlias.create(:antecedent_name => "bbb", :consequent_name => "ddd", :updater_id => ta1.creator_id, :updater_ip_addr => "127.0.0.1")
+        assert(ta3.errors.any?, "Tag alias should be invalid")
+        assert_equal("Tag alias can not create a transitive relation with another tag alias", ta3.errors.full_messages.join)
+      end
+    end
   end
 end
diff --git a/test/unit/tag_implication_test.rb b/test/unit/tag_implication_test.rb
index d0316032b..c606cbb77 100644
--- a/test/unit/tag_implication_test.rb
+++ b/test/unit/tag_implication_test.rb
@@ -1,8 +1,45 @@
-require 'test_helper'
+require File.dirname(__FILE__) + '/../test_helper'
 
 class TagImplicationTest < ActiveSupport::TestCase
-  # Replace this with your real tests.
-  test "the truth" do
-    assert true
+  context "A tag implication" do
+    setup do
+      MEMCACHE.flush_all
+      @user = Factory.create(:user)
+    end
+
+    should "clear the cache upon saving" do
+      ti1 = Factory.create(:tag_implication, :antecedent_name => "aaa", :consequent_name => "bbb")
+      assert_equal(["bbb"], ti1.descendant_names_array)
+      assert_equal(["bbb"], MEMCACHE.get("ti:aaa"))
+      ti1.update_attributes(
+        :consequent_name => "ccc",
+        :updater_id => @user.id,
+        :updater_ip_addr => "127.0.0.1"
+      )
+      assert_nil(MEMCACHE.get("ti:aaa"))
+    end
+    
+    # should "clear the cache upon destruction" do
+    #   ti1 = Factory.create(:tag_implication, :antecedent_name => "aaa", :consequent_name => "bbb")
+    #   assert_equal("bbb", ti1.descendant_names)
+    #   assert_equal(["bbb"], ti1.descendant_names_array)
+    #   assert_equal(["bbb"], MEMCACHE.get("ti:aaa"))
+    #   ti1.destroy
+    #   assert_nil(MEMCACHE.get("ti:aaa"))
+    # end
+    # 
+    # should "calculate all its descendants" do
+    #   ti1 = Factory.create(:tag_implication, :antecedent_name => "bbb", :consequent_name => "ccc")
+    #   assert_equal(["ccc"], ti1.descendant_names_array)      
+    #   ti2 = Factory.create(:tag_implication, :antecedent_name => "aaa", :consequent_name => "bbb")
+    #   assert_equal(["bbb", "ccc"], ti2.descendant_names_array)
+    #   ti1.reload
+    #   assert_equal(["ccc"], ti1.descendant_names_array)
+    # end
+    
+    should "cache its descendants"
+    should "update its descendants on save"
+    should "update the decendants for its parent on save"
+    should "update any affected post upon save"
   end
 end
diff --git a/test/unit/upload_test.rb b/test/unit/upload_test.rb
index b2b408dcd..9dc4c5a6c 100644
--- a/test/unit/upload_test.rb
+++ b/test/unit/upload_test.rb
@@ -8,21 +8,21 @@ class UploadTest < ActiveSupport::TestCase
 
     context "image size calculator" do
       should "discover the dimensions for a JPG" do
-        @upload = Factory.create(:uploaded_jpg_upload)
+        @upload = Factory.create(:jpg_upload)
         assert_nothing_raised {@upload.calculate_dimensions(@upload.file_path)}
         assert_equal(500, @upload.image_width)
         assert_equal(335, @upload.image_height)
       end
 
       should "discover the dimensions for a PNG" do
-        @upload = Factory.create(:uploaded_png_upload)
+        @upload = Factory.create(:png_upload)
         assert_nothing_raised {@upload.calculate_dimensions(@upload.file_path)}
         assert_equal(768, @upload.image_width)
         assert_equal(1024, @upload.image_height)
       end
 
       should "discover the dimensions for a GIF" do
-        @upload = Factory.create(:uploaded_gif_upload)
+        @upload = Factory.create(:gif_upload)
         assert_nothing_raised {@upload.calculate_dimensions(@upload.file_path)}
         assert_equal(400, @upload.image_width)
         assert_equal(400, @upload.image_height)
@@ -31,7 +31,7 @@ class UploadTest < ActiveSupport::TestCase
     
     context "content type calculator" do
       should "know how to parse jpeg, png, gif, and swf file extensions" do
-        @upload = Factory.create(:uploaded_jpg_upload)
+        @upload = Factory.create(:jpg_upload)
         assert_equal("image/jpeg", @upload.file_ext_to_content_type("test.jpeg"))
         assert_equal("image/gif", @upload.file_ext_to_content_type("test.gif"))
         assert_equal("image/png", @upload.file_ext_to_content_type("test.png"))
@@ -40,7 +40,7 @@ class UploadTest < ActiveSupport::TestCase
       end
 
       should "know how to parse jpeg, png, gif, and swf content types" do
-        @upload = Factory.create(:uploaded_jpg_upload)
+        @upload = Factory.create(:jpg_upload)
         assert_equal("jpg", @upload.content_type_to_file_ext("image/jpeg"))
         assert_equal("gif", @upload.content_type_to_file_ext("image/gif"))
         assert_equal("png", @upload.content_type_to_file_ext("image/png"))
@@ -51,7 +51,7 @@ class UploadTest < ActiveSupport::TestCase
     
     context "downloader" do
       should "initialize the final path and content type after downloading a file" do
-        @upload = Factory.create(:downloadable_upload)
+        @upload = Factory.create(:source_upload)
         path = "#{Rails.root}/tmp/test.download.jpg"
         assert_nothing_raised {@upload.download_from_source(path)}
         assert(File.exists?(path))
@@ -76,7 +76,7 @@ class UploadTest < ActiveSupport::TestCase
 
     context "hash calculator" do
       should "caculate the hash" do
-        @upload = Factory.create(:uploaded_jpg_upload)
+        @upload = Factory.create(:jpg_upload)
         @upload.calculate_hash(@upload.file_path)
         assert_equal("ecef68c44edb8a0d6a3070b5f8e8ee76", @upload.md5)
       end
@@ -91,7 +91,7 @@ class UploadTest < ActiveSupport::TestCase
       end
       
       should "generate several resized versions of the image" do
-        @upload = Factory.create(:uploaded_large_jpg_upload)
+        @upload = Factory.create(:large_jpg_upload)
         @upload.calculate_hash(@upload.file_path)
         @upload.calculate_dimensions(@upload.file_path)
         assert_nothing_raised {@upload.generate_resizes(@upload.file_path)}
@@ -105,7 +105,7 @@ class UploadTest < ActiveSupport::TestCase
     end
     
     should "process completely for a downloaded image" do
-      @upload = Factory.create(:downloadable_upload,
+      @upload = Factory.create(:source_upload,
         :rating => "s",
         :uploader_ip_addr => "127.0.0.1",
         :tag_string => "hoge foo"
@@ -130,7 +130,7 @@ class UploadTest < ActiveSupport::TestCase
   end
   
   should "process completely for an uploaded image" do
-    @upload = Factory.create(:uploaded_jpg_upload,
+    @upload = Factory.create(:jpg_upload,
       :rating => "s",
       :uploader_ip_addr => "127.0.0.1",
       :tag_string => "hoge foo"