auto replace rules in titles

app/controllers/posts_controller.rb

@@ -40,12 +40,12 @@ class PostsController < ApplicationController
     post.image_sizes = params[:image_sizes] if params[:image_sizes].present?
     guardian.ensure_can_edit!(post)
 
-    # to stay consistent with the create api, 
+    # to stay consistent with the create api,
     #  we should allow for title changes and category changes here
     # we should also move all of this to a post updater.
-    if post.post_number == 1 && (params[:title] || params[:post][:category]) 
+    if post.post_number == 1 && (params[:title] || params[:post][:category])
       post.topic.title = params[:title] if params[:title]
-      Topic.transaction do 
+      Topic.transaction do
         post.topic.change_category(params[:post][:category])
         post.topic.save
       end

app/controllers/topics_controller.rb

@@ -56,7 +56,9 @@ class TopicsController < ApplicationController
       topic.change_category(params[:category])
     end
 
-    render nothing: true
+    # this is used to return the title to the client as it may have been
+    # changed by "TextCleaner"
+    render_serialized(topic, BasicTopicSerializer)
   end
 
   def similar_to

app/models/post.rb

@@ -52,16 +52,10 @@ class Post < ActiveRecord::Base
   end
 
   def raw_quality
-    sentinel = TextSentinel.new(raw, min_entropy: SiteSetting.body_min_entropy)
-    if sentinel.valid?
-      # It's possible the sentinel has cleaned up the title a bit
-      self.raw = sentinel.text
-    else
-      errors.add(:raw, I18n.t(:is_invalid)) unless sentinel.valid?
-    end
+    sentinel = TextSentinel.body_sentinel(raw)
+    errors.add(:raw, I18n.t(:is_invalid)) unless sentinel.valid?
   end
 
-
   # Stop us from posting the same thing too quickly
   def unique_post_validator
     return if SiteSetting.unique_posts_mins == 0

app/models/post_action.rb

@@ -118,12 +118,7 @@ class PostAction < ActiveRecord::Base
   def message_quality
     return if message.blank?
     sentinel = TextSentinel.title_sentinel(message)
-    if sentinel.valid?
-      # It's possible the sentinel has cleaned up the title a bit
-      self.message = sentinel.text
-    else
-      errors.add(:message, I18n.t(:is_invalid)) unless sentinel.valid?
-    end
+    errors.add(:message, I18n.t(:is_invalid)) unless sentinel.valid?
   end
 
   before_create do

app/models/site_setting.rb

@@ -42,6 +42,9 @@ class SiteSetting < ActiveRecord::Base
   # cf. https://github.com/discourse/discourse/pull/462#issuecomment-14991562
   client_setting(:category_colors, 'BF1E2E|F1592A|F7941D|9EB83B|3AB54A|12A89D|25AAE2|0E76BD|652D90|92278F|ED207B|8C6238|231F20|808281|B3B5B4|283890')
 
+  # auto-replace rules for title
+  setting(:title_prettify, true)
+
   client_setting(:max_upload_size_kb, 1024)
 
   # settings only available server side

app/models/topic.rb

@@ -3,6 +3,7 @@ require_dependency 'avatar_lookup'
 require_dependency 'topic_view'
 require_dependency 'rate_limiter'
 require_dependency 'text_sentinel'
+require_dependency 'text_cleaner'
 
 class Topic < ActiveRecord::Base
   include ActionView::Helpers
@@ -143,8 +144,8 @@ class Topic < ActiveRecord::Base
 
     sentinel = TextSentinel.title_sentinel(title)
     if sentinel.valid?
-      # It's possible the sentinel has cleaned up the title a bit
-      self.title = sentinel.text
+      # clean up the title
+      self.title = TextCleaner.clean_title(sentinel.text)
     else
       errors.add(:title, I18n.t(:is_invalid))
     end

config/locales/server.en.yml

@@ -495,6 +495,8 @@ en:
     max_upload_size_kb: "The maximum size of files we allow users to upload in kb - be sure to configure the limit in nginx (client_max_body_size) / apache or proxy as well."
     max_similar_results: "How many similar topics to show a user while they are composing a new topic"
 
+    title_prettify: "Prevent common title typos and errors, including all caps, lowercase first character, multiple ! and ?, extra . at end, etc."
+
   notification_types:
     mentioned: "%{display_username} mentioned you in %{link}"
     liked: "%{display_username} liked your post in %{link}"

config/locales/server.fr.yml

@@ -502,6 +502,8 @@ fr:
     max_upload_size_kb: "La taille maximum des fichiers que les utilisateurs peuvent envoyer en Kb - assurez-vous de configurer également cette limite dans nginx (client_max_body_size) / apache ou votre proxy."
     max_similar_results: "Nombre de discussions similaires à afficher lorsqu'un utilisateur est en train de créer une nouvelle discussion"
 
+    title_prettify: "Corrige les coquilles les plus communes dans les titres (intégralité du titre en majuscule, première lettre en minuscule, de multiples ! et ?, un . inutile à la fin, etc.)"
+
   notification_types:
     mentioned: "%{display_username} vous a mentionné dans %{link}"
     liked: "%{display_username} a aimé votre message dans %{link}"

lib/text_cleaner.rb

@@ -0,0 +1,45 @@
+#
+# Clean up a text
+#
+class TextCleaner
+
+  def self.title_options
+    # cf. http://meta.discourse.org/t/should-we-have-auto-replace-rules-in-titles/5687
+    {
+      deduplicate_exclamation_marks: SiteSetting.title_prettify,
+      deduplicate_question_marks: SiteSetting.title_prettify,
+      replace_all_upper_case: SiteSetting.title_prettify,
+      capitalize_first_letter: SiteSetting.title_prettify,
+      remove_unnecessary_period: SiteSetting.title_prettify,
+      remove_extraneous_space: SiteSetting.title_prettify && SiteSetting.default_locale == "en",
+      fixes_interior_spaces: true,
+      strip_whitespaces: true
+    }
+  end
+
+  def self.clean_title(title)
+    TextCleaner.clean(title, TextCleaner.title_options)
+  end
+
+  def self.clean(text, opts = {})
+    # Replace !!!!! with a single !
+    text.gsub!(/!+/, '!') if opts[:deduplicate_exclamation_marks]
+    # Replace ????? with a single ?
+    text.gsub!(/\?+/, '?') if opts[:deduplicate_question_marks]
+    # Replace all-caps text with regular case letters
+    text.tr!('A-Z', 'a-z') if opts[:replace_all_upper_case] && (text =~ /[A-Z]+/) && (text == text.upcase)
+    # Capitalize first letter
+    text.sub!(/\A([a-z])/) { |first| first.capitalize } if opts[:capitalize_first_letter]
+    # Remove unnecessary period at the end
+    text.sub!(/([^.])\.(\s*)\z/, '\1\2') if opts[:remove_unnecessary_period]
+    # Remove extraneous space before the end punctuation
+    text.sub!(/\s+([!?]\s*)\z/, '\1') if opts[:remove_extraneous_space]
+    # Fixes interior spaces
+    text.gsub!(/ +/, ' ') if opts[:fixes_interior_spaces]
+    # Strip whitespaces
+    text.strip! if opts[:strip_whitespaces]
+
+    text
+  end
+
+end

lib/text_sentinel.rb

@@ -1,31 +1,27 @@
 #
-# Given a string, tell us whether or not is acceptable. Also, remove stuff we don't like
-# such as leading / trailing space.
+# Given a string, tell us whether or not is acceptable.
 #
 class TextSentinel
 
   attr_accessor :text
 
+  def initialize(text, opts=nil)
+    @opts = opts || {}
+    @text = text.encode('UTF-8', invalid: :replace, undef: :replace, replace: '') if text.present?
+  end
+
   def self.non_symbols_regexp
     /[\ -\/\[-\`\:-\@\{-\~]/m
   end
 
-  def initialize(text, opts=nil)
-    @opts = opts || {}
-
-    if text.present?
-      @text = text.encode('UTF-8', invalid: :replace, undef: :replace, replace: '')
-      @text.gsub!(/ +/m, ' ') if @opts[:remove_interior_spaces]
-      @text.strip! if @opts[:strip]
-    end
+  def self.body_sentinel(text)
+    TextSentinel.new(text, min_entropy: SiteSetting.body_min_entropy)
   end
 
   def self.title_sentinel(text)
     TextSentinel.new(text,
                      min_entropy: SiteSetting.title_min_entropy,
-                     max_word_length: SiteSetting.max_word_length,
-                     remove_interior_spaces: true,
-                     strip: true)
+                     max_word_length: SiteSetting.max_word_length)
   end
 
   # Entropy is a number of how many unique characters the string needs.
@@ -35,7 +31,6 @@ class TextSentinel
   end
 
   def valid?
-
     # Blank strings are not valid
     return false if @text.blank? || @text.strip.blank?
 
@@ -47,12 +42,12 @@ class TextSentinel
     return false if non_symbols == 0
 
     # Don't allow super long strings without spaces
-
     return false if @opts[:max_word_length] && @text =~ /\w{#{@opts[:max_word_length]},}(\s|$)/
 
     # We don't allow all upper case content in english
     return false if (@text =~ /[A-Z]+/) && (@text == @text.upcase)
 
+    # It is valid
     true
   end
 

spec/components/text_cleaner_spec.rb

@@ -0,0 +1,193 @@
+require 'spec_helper'
+require 'text_cleaner'
+
+describe TextCleaner do
+
+  context "exclamation marks" do
+
+    let(:duplicated_string) { "my precious!!!!" }
+    let(:deduplicated_string) { "my precious!" }
+
+    it "ignores multiple ! by default" do
+      TextCleaner.clean(duplicated_string).should == duplicated_string
+    end
+
+    it "deduplicates ! when enabled" do
+      TextCleaner.clean(duplicated_string, deduplicate_exclamation_marks: true).should == deduplicated_string
+    end
+
+  end
+
+  context "question marks" do
+
+    let(:duplicated_string) { "please help me????" }
+    let(:deduplicated_string) { "please help me?" }
+
+    it "ignores multiple ? by default" do
+      TextCleaner.clean(duplicated_string).should == duplicated_string
+    end
+
+    it "deduplicates ? when enabled" do
+      TextCleaner.clean(duplicated_string, deduplicate_question_marks: true).should == deduplicated_string
+    end
+
+  end
+
+  context "all upper case text" do
+
+    let(:all_caps) { "ENTIRE TEXT IS ALL CAPS" }
+    let(:almost_all_caps) { "ENTIRE TEXT iS ALL CAPS" }
+    let(:regular_case) { "entire text is all caps" }
+
+    it "ignores all upper case text by default" do
+      TextCleaner.clean(all_caps).should == all_caps
+    end
+
+    it "replaces all upper case text with regular case letters when enabled" do
+      TextCleaner.clean(all_caps, replace_all_upper_case: true).should == regular_case
+    end
+
+    it "ignores almost all upper case text when enabled" do
+      TextCleaner.clean(almost_all_caps, replace_all_upper_case: true).should == almost_all_caps
+    end
+
+  end
+
+  context "first letter" do
+
+    let(:lowercased) { "this is awesome" }
+    let(:capitalized) { "This is awesome" }
+
+    it "ignores first letter case by default" do
+      TextCleaner.clean(lowercased).should == lowercased
+      TextCleaner.clean(capitalized).should == capitalized
+    end
+
+    it "capitalizes first letter when enabled" do
+      TextCleaner.clean(lowercased, capitalize_first_letter: true).should == capitalized
+      TextCleaner.clean(capitalized, capitalize_first_letter: true).should == capitalized
+    end
+
+  end
+
+  context "period at the end" do
+
+    let(:with_period) { "oops." }
+    let(:with_periods) { "oops..." }
+    let(:without_period) { "oops" }
+
+    it "ignores unnecessary period at the end by default" do
+      TextCleaner.clean(with_period).should == with_period
+    end
+
+    it "removes unnecessary period at the end when enabled" do
+      TextCleaner.clean(with_period, remove_unnecessary_period: true).should == without_period
+    end
+
+    it "keeps ellipsis when enabled" do
+      TextCleaner.clean(with_periods, remove_unnecessary_period: true).should == with_periods
+    end
+
+    it "keeps trailing whitespaces when enabled" do
+      TextCleaner.clean(with_periods + " ", remove_unnecessary_period: true).should == with_periods + " "
+    end
+
+  end
+
+  context "extraneous space" do
+
+    let(:with_space_exclamation) { "oops !" }
+    let(:without_space_exclamation) { "oops!" }
+    let(:with_space_question) { "oops ?" }
+    let(:without_space_question) { "oops?" }
+
+    it "ignores extraneous space before the end punctuation by default" do
+      TextCleaner.clean(with_space_exclamation).should == with_space_exclamation
+      TextCleaner.clean(with_space_question).should == with_space_question
+    end
+
+    it "removes extraneous space before the end punctuation when enabled" do
+      TextCleaner.clean(with_space_exclamation, remove_extraneous_space: true).should == without_space_exclamation
+      TextCleaner.clean(with_space_question, remove_extraneous_space: true).should == without_space_question
+    end
+
+    it "keep trailing whitespaces when enabled" do
+      TextCleaner.clean(with_space_exclamation + " ", remove_extraneous_space: true).should == without_space_exclamation + " "
+      TextCleaner.clean(with_space_question + " ", remove_extraneous_space: true).should == without_space_question + " "
+    end
+
+  end
+
+  context "interior spaces" do
+
+    let(:spacey_string) { "hello     there's weird     spaces here." }
+    let(:unspacey_string) { "hello there's weird spaces here." }
+
+    it "ignores interior spaces by default" do
+      TextCleaner.clean(spacey_string).should == spacey_string
+    end
+
+    it "fixes interior spaces when enabled" do
+      TextCleaner.clean(spacey_string, fixes_interior_spaces: true).should == unspacey_string
+    end
+
+  end
+
+  context "leading and trailing whitespaces" do
+
+    let(:spacey_string) { "   \t  test \n  " }
+    let(:unspacey_string) { "test" }
+
+    it "ignores leading and trailing whitespaces by default" do
+      TextCleaner.clean(spacey_string).should == spacey_string
+    end
+
+    it "strips leading and trailing whitespaces when enabled" do
+      TextCleaner.clean(spacey_string, strip_whitespaces: true).should == unspacey_string
+    end
+
+  end
+
+  context "title" do
+
+    it "fixes interior spaces" do
+      TextCleaner.clean_title("Hello   there").should == "Hello there"
+    end
+
+    it "strips leading and trailing whitespaces" do
+      TextCleaner.clean_title(" \t Hello there \n ").should == "Hello there"
+    end
+
+    context "title_prettify site setting is enabled" do
+
+      before { SiteSetting.title_prettify = true }
+
+      it "deduplicates !" do
+        TextCleaner.clean_title("Hello there!!!!").should == "Hello there!"
+      end
+
+      it "deduplicates ?" do
+        TextCleaner.clean_title("Hello there????").should == "Hello there?"
+      end
+
+      it "replaces all upper case text with regular case letters" do
+        TextCleaner.clean_title("HELLO THERE").should == "Hello there"
+      end
+
+      it "capitalizes first letter" do
+        TextCleaner.clean_title("hello there").should == "Hello there"
+      end
+
+      it "removes unnecessary period at the end" do
+        TextCleaner.clean_title("Hello there.").should == "Hello there"
+      end
+
+      it "removes extraneous space before the end punctuation" do
+        TextCleaner.clean_title("Hello there ?").should == "Hello there?"
+      end
+
+    end
+
+  end
+
+end

spec/components/text_sentinel_spec.rb

@@ -5,10 +5,12 @@ require 'text_sentinel'
 
 describe TextSentinel do
 
+  it "allows utf-8 chars" do
+    TextSentinel.new("йȝîûηыეமிᚉ⠛").text.should == "йȝîûηыეமிᚉ⠛"
+  end
 
   context "entropy" do
 
-
     it "returns 0 for an empty string" do
       TextSentinel.new("").entropy.should == 0
     end
@@ -35,50 +37,6 @@ describe TextSentinel do
 
   end
 
-  context "cleaning up" do
-
-    it "allows utf-8 chars" do
-      TextSentinel.new("йȝîûηыეமிᚉ⠛").text.should == "йȝîûηыეமிᚉ⠛"
-    end
-
-    context "interior spaces" do
-
-      let(:spacey_string) { "hello     there's weird     spaces here." }
-      let(:unspacey_string) { "hello there's weird spaces here." }
-
-      it "ignores intra spaces by default" do
-        TextSentinel.new(spacey_string).text.should == spacey_string
-      end
-
-      it "fixes intra spaces when enabled" do
-        TextSentinel.new(spacey_string, remove_interior_spaces: true).text.should == unspacey_string
-      end
-
-      it "fixes intra spaces in titles" do
-        TextSentinel.title_sentinel(spacey_string).text.should == unspacey_string
-      end
-
-    end
-
-    context "stripping whitespace" do
-      let(:spacey_string) { "   \t  test \t  " }
-      let(:unspacey_string) { "test" }
-
-      it "does not strip leading and trailing whitespace by default" do
-        TextSentinel.new(spacey_string).text.should == spacey_string
-      end
-
-      it "strips leading and trailing whitespace when enabled" do
-        TextSentinel.new(spacey_string, strip: true).text.should == unspacey_string
-      end
-
-      it "strips leading and trailing whitespace in titles" do
-        TextSentinel.title_sentinel(spacey_string).text.should == unspacey_string
-      end
-    end
-
-  end
-
   context "validity" do
 
     let(:valid_string) { "This is a cool topic about Discourse" }
@@ -113,8 +71,6 @@ describe TextSentinel do
       TextSentinel.new("{{$!").should_not be_valid
     end
 
-
   end
 
-
 end

spec/controllers/topics_controller_spec.rb

@@ -407,12 +407,13 @@ describe TopicsController do
         it 'succeeds' do
           xhr :put, :update, topic_id: @topic.id, slug: @topic.title
           response.should be_success
+          ::JSON.parse(response.body)['basic_topic'].should be_present
         end
 
         it 'allows a change of title' do
-          xhr :put, :update, topic_id: @topic.id, slug: @topic.title, title: 'this is a new title for the topic'
+          xhr :put, :update, topic_id: @topic.id, slug: @topic.title, title: 'This is a new title for the topic'
           @topic.reload
-          @topic.title.should == 'this is a new title for the topic'
+          @topic.title.should == 'This is a new title for the topic'
         end
 
         it 'triggers a change of category' do

spec/models/topic_spec.rb

@@ -111,20 +111,20 @@ describe Topic do
   end
 
   context 'html in title' do
-    let(:topic_bold) { Fabricate(:topic, title: "topic with <b>bold</b> text in its title" ) }
-    let(:topic_image) { Fabricate(:topic, title: "topic with <img src='something'> image in its title" ) }
-    let(:topic_script) { Fabricate(:topic, title: "<script>alert('title')</script> is my topic title" ) }
+    let(:topic_bold) { Fabricate(:topic, title: "Topic with <b>bold</b> text in its title" ) }
+    let(:topic_image) { Fabricate(:topic, title: "Topic with <img src='something'> image in its title" ) }
+    let(:topic_script) { Fabricate(:topic, title: "Topic with <script>alert('title')</script> script in its title" ) }
 
     it "escapes script contents" do
-      topic_script.title.should == "is my topic title"
+      topic_script.title.should == "Topic with script in its title"
     end
 
     it "escapes bold contents" do
-      topic_bold.title.should == "topic with bold text in its title"
+      topic_bold.title.should == "Topic with bold text in its title"
     end
 
-    it "escapes bold contents" do
-      topic_image.title.should == "topic with image in its title"
+    it "escapes image contents" do
+      topic_image.title.should == "Topic with image in its title"
     end
 
   end