Fix rubocop offenses

app/controllers/concerns/file_parameters.rb

@@ -6,7 +6,7 @@ module FileParameters
       params.reject do |_, file_attributes|
         file = CodeOcean::File.find_by(id: file_attributes[:file_id])
         # avoid that public files from other contexts can be created
-        file.nil? || file.hidden || file.read_only || file.context_type == 'Exercise' && file.context_id != exercise.id
+        file.nil? || file.hidden || file.read_only || (file.context_type == 'Exercise' && file.context_id != exercise.id)
       end
     else
       []

app/helpers/time_helper.rb

@@ -5,7 +5,7 @@ module TimeHelper
   def time_to_f(timestamp)
     unless timestamp.nil?
       timestamp = timestamp.split(':')
-      return timestamp[0].to_i * 60 * 60 + timestamp[1].to_i * 60 + timestamp[2].to_f
+      return (timestamp[0].to_i * 60 * 60) + (timestamp[1].to_i * 60) + timestamp[2].to_f
     end
     nil
   end

app/models/exercise.rb

@@ -68,7 +68,9 @@ class Exercise < ApplicationRecord
     if submissions.exists?(cause: 'submit')
       maximum_scores_query = submissions.select('MAX(score) AS maximum_score').group(:user_id).to_sql.sub('$1', id.to_s)
       self.class.connection.execute("SELECT AVG(maximum_score) AS average_score FROM (#{maximum_scores_query}) AS maximum_scores").first['average_score'].to_f
-    else 0 end
+    else
+      0
+    end
   end
 
   def average_number_of_submissions

app/models/proxy_exercise.rb

@@ -240,7 +240,7 @@ class ProxyExercise < ApplicationRecord
 
   def tag_diminishing_return_function(count_tag, total_count_tag)
     total_count_tag += 1 # bonus exercise comes on top
-    1 / (1 + (Math::E**(-3 / (0.5 * total_count_tag) * (count_tag - 0.5 * total_count_tag))))
+    1 / (1 + (Math::E**(-3 / (0.5 * total_count_tag) * (count_tag - (0.5 * total_count_tag)))))
   end
 
   def select_easiest_exercise(exercises)

app/policies/exercise_policy.rb

@@ -6,7 +6,7 @@ class ExercisePolicy < AdminOrAuthorPolicy
   end
 
   %i[show? feedback? statistics? rfcs_for_exercise?].each do |action|
-    define_method(action) { admin? || teacher_in_study_group? || teacher? && @record.public? || author? }
+    define_method(action) { admin? || teacher_in_study_group? || (teacher? && @record.public?) || author? }
   end
 
   def study_group_dashboard?

app/policies/proxy_exercise_policy.rb

@@ -6,7 +6,7 @@ class ProxyExercisePolicy < AdminOrAuthorPolicy
   end
 
   def show?
-    admin? || teacher_in_study_group? || teacher? && @record.public? || author?
+    admin? || teacher_in_study_group? || (teacher? && @record.public?) || author?
   end
 
   %i[clone? destroy? edit? update?].each do |action|

app/policies/study_group_policy.rb

@@ -6,7 +6,7 @@ class StudyGroupPolicy < AdminOnlyPolicy
   end
 
   %i[show? destroy? edit? update? stream_la?].each do |action|
-    define_method(action) { admin? || @user.teacher? && @record.present? && @user.study_groups.exists?(@record.id) }
+    define_method(action) { admin? || (@user.teacher? && @record.present? && @user.study_groups.exists?(@record.id)) }
   end
 
   class Scope < Scope

lib/tasks/detect_exercise_anomalies.rake

@@ -51,7 +51,7 @@ namespace :detect_exercise_anomalies do
   end
 
   def log(message = '', indent_level = 0, prefix = '')
-    puts("\t" * indent_level + "#{prefix}#{message}")
+    puts(("\t" * indent_level) + "#{prefix}#{message}")
   end
 
   def get_collections(number_of_exercises, number_of_solutions)

spec/models/submission_spec.rb

@@ -93,7 +93,7 @@ describe Submission do
   describe '#redirect_to_feedback?' do
     context 'with no exercise feedback' do
       let(:exercise) { FactoryBot.create(:dummy) }
-      let(:user) { FactoryBot.build(:external_user, id: (11 - exercise.created_at.to_i % 10) % 10) }
+      let(:user) { FactoryBot.build(:external_user, id: (11 - (exercise.created_at.to_i % 10)) % 10) }
       let(:submission) { FactoryBot.build(:submission, exercise: exercise, user: user) }
 
       it 'sends 10% of users to feedback page' do
@@ -102,7 +102,7 @@ describe Submission do
 
       it 'does not redirect other users' do
         9.times do |i|
-          submission = FactoryBot.build(:submission, exercise: exercise, user: FactoryBot.build(:external_user, id: (11 - exercise.created_at.to_i % 10) - i - 1))
+          submission = FactoryBot.build(:submission, exercise: exercise, user: FactoryBot.build(:external_user, id: (11 - (exercise.created_at.to_i % 10)) - i - 1))
           expect(submission.send(:redirect_to_feedback?)).to be_falsey
         end
       end
@@ -110,7 +110,7 @@ describe Submission do
 
     context 'with little exercise feedback' do
       let(:exercise) { FactoryBot.create(:dummy_with_user_feedbacks) }
-      let(:user) { FactoryBot.build(:external_user, id: (11 - exercise.created_at.to_i % 10) % 10) }
+      let(:user) { FactoryBot.build(:external_user, id: (11 - (exercise.created_at.to_i % 10)) % 10) }
       let(:submission) { FactoryBot.build(:submission, exercise: exercise, user: user) }
 
       it 'sends 10% of users to feedback page' do
@@ -119,7 +119,7 @@ describe Submission do
 
       it 'does not redirect other users' do
         9.times do |i|
-          submission = FactoryBot.build(:submission, exercise: exercise, user: FactoryBot.build(:external_user, id: (11 - exercise.created_at.to_i % 10) - i - 1))
+          submission = FactoryBot.build(:submission, exercise: exercise, user: FactoryBot.build(:external_user, id: (11 - (exercise.created_at.to_i % 10)) - i - 1))
           expect(submission.send(:redirect_to_feedback?)).to be_falsey
         end
       end

spec/services/proforma_service/convert_task_to_exercise_spec.rb

@@ -118,7 +118,7 @@ describe ProformaService::ConvertTaskToExercise do
       end
 
       context 'when file is very large' do
-        let(:content) { 'test' * 10**5 }
+        let(:content) { 'test' * (10**5) }
 
         it 'creates an exercise with a file that has the correct attributes' do
           expect(convert_to_exercise_service.files.first).to have_attributes(content: content)

spec/services/proforma_service/import_spec.rb

@@ -83,7 +83,7 @@ describe ProformaService::Import do
       it { is_expected.to be_an_equal_exercise_as exercise }
 
       context 'when the mainfile is very large' do
-        let(:file) { FactoryBot.build(:file, content: 'test' * 10**5) }
+        let(:file) { FactoryBot.build(:file, content: 'test' * (10**5)) }
 
         it { is_expected.to be_an_equal_exercise_as exercise }
       end