Move math around parenthases in score_experience_level (#6569) [deploy]

* Move math around parenthases in score_experience_level

* Clean up tests

* Remove flash notice from comments form

app/services/articles/feed.rb

@@ -139,7 +139,7 @@ module Articles
     end
 
     def score_experience_level(article)
-      - ((article.experience_level_rating - (@user&.experience_level || 5).abs) / 2)
+      - ((article.experience_level_rating - (@user&.experience_level || 5)).abs / 2)
     end
 
     def score_comments(article)

spec/services/articles/feed_spec.rb

@@ -350,21 +350,34 @@ RSpec.describe Articles::Feed, type: :service do
   end
 
   describe "#score_experience_level" do
-    let(:article) { create(:article, experience_level_rating: 9) }
+    let(:article) { create(:article, experience_level_rating: 7) }
 
-    context "when user has an experience level" do
-      let(:user) { create(:user, experience_level: 3) }
+    context "when user has a further experience level" do
+      let(:user) { create(:user, experience_level: 1) }
 
       it "returns negative of (absolute value of the difference between article and user experience) divided by 2" do
         expect(feed.score_experience_level(article)).to eq(-3)
       end
+
+      it "returns  proper negative when fractional" do
+        article.experience_level_rating = 8
+        expect(feed.score_experience_level(article)).to eq(-3.5)
+      end
+    end
+
+    context "when user has a closer experience level" do
+      let(:user) { create(:user, experience_level: 9) }
+
+      it "returns negative of (absolute value of the difference between article and user experience) divided by 2" do
+        expect(feed.score_experience_level(article)).to eq(-1)
+      end
     end
 
     context "when the user does not have an experience level set" do
       let(:user) { create(:user, experience_level: nil) }
 
       it "uses a value of 5 for user experience level" do
-        expect(feed.score_experience_level(article)).to eq(-2)
+        expect(feed.score_experience_level(article)).to eq(-1)
       end
     end
   end