FEATURE: Improve errors when title is invalid (#11149)

It used to simply say "title is invalid" without giving any hint what
the problem could be. This commit adds different errors messages for
all caps titles, low entropy titles or titles with very long words.

spec/components/validators/quality_title_validator_spec.rb

@@ -18,6 +18,10 @@ describe "A record validated with QualityTitleValidator" do
   let(:long_title) { valid_title.center(SiteSetting.max_topic_title_length + 1, 'x') }
   let(:xxxxx_title) { valid_title.gsub(/./, 'x') }
 
+  let(:meaningless_title) { "asdf asdf asdf" }
+  let(:loud_title) { "ALL CAPS INVALID TITLE" }
+  let(:pretentious_title) { "superverylongwordintitlefornoparticularreason" }
+
   subject(:topic) { QualityTitleValidatorSpec::Validatable.new }
 
   before(:each) do
@@ -67,12 +71,21 @@ describe "A record validated with QualityTitleValidator" do
     expect(topic).not_to be_valid
   end
 
-  # describe "with a name" do
-  #   it "is not valid without a name" do
-  #     subject.stub(:name => nil)
-  #     subject.should_not be_valid
-  #     subject.should have(1).error_on(:name)
-  #     subject.errors[:name].first.should == "can't be blank"
-  #   end
-  # end
+  it "doesn't allow a meaningless title" do
+    topic.title = meaningless_title
+    expect(topic).not_to be_valid
+    expect(topic.errors.full_messages.first).to include(I18n.t("errors.messages.is_invalid_meaningful"))
+  end
+
+  it "doesn't allow a pretentious title" do
+    topic.title = pretentious_title
+    expect(topic).not_to be_valid
+    expect(topic.errors.full_messages.first).to include(I18n.t("errors.messages.is_invalid_unpretentious"))
+  end
+
+  it "doesn't allow a loud title" do
+    topic.title = loud_title
+    expect(topic).not_to be_valid
+    expect(topic.errors.full_messages.first).to include(I18n.t("errors.messages.is_invalid_quiet"))
+  end
 end