Optimize the `award_user_list` helper spec

According to
https://gitlab.com/gitlab-org/gitlab-ce/issues/23034#note_16586657, each
test for this helper generated 1,833 queries.

Now we only generate stubbed records, and only as many as we need for
each test.

This also corrects a slight logic bug in the helper itself. When the
number of awards was greater than the limit (9 by default), _and_ the
current user was one of them, we actually included 10 names, including
"You", plus the remaining count. Now we return the correct number
regardless.

app/helpers/issues_helper.rb

@@ -113,14 +113,13 @@ module IssuesHelper
     end
   end
 
-  def award_user_list(awards, current_user)
+  def award_user_list(awards, current_user, limit: 10)
     names = awards.map do |award|
       award.user == current_user ? 'You' : award.user.name
     end
 
-    # Take first 9 OR current user + first 9
     current_user_name = names.delete('You')
-    names = names.first(9).insert(0, current_user_name).compact
+    names = names.insert(0, current_user_name).compact.first(limit)
 
     names << "#{awards.size - names.size} more." if awards.size > names.size
 

spec/helpers/issues_helper_spec.rb

@@ -63,28 +63,38 @@ describe IssuesHelper do
   end
 
   describe '#award_user_list' do
-    let!(:awards) { build_list(:award_emoji, 15) }
+    it "returns a comma-separated list of the first X users" do
+      user = build_stubbed(:user, name: 'Joe')
+      awards = Array.new(3, build_stubbed(:award_emoji, user: user))
 
-    it "returns a comma seperated list of 1-9 users" do
-      expect(award_user_list(awards.first(9), nil)).to eq(awards.first(9).map { |a| a.user.name }.to_sentence)
+      expect(award_user_list(awards, nil, limit: 3))
+        .to eq('Joe, Joe, and Joe')
     end
 
     it "displays the current user's name as 'You'" do
-      expect(award_user_list(awards.first(1), awards[0].user)).to eq('You')
-    end
+      user = build_stubbed(:user, name: 'Joe')
+      award = build_stubbed(:award_emoji, user: user)
 
-    it "truncates lists of larger than 9 users" do
-      expect(award_user_list(awards, nil)).to eq(awards.first(9).map { |a| a.user.name }.join(', ') + ", and 6 more.")
+      expect(award_user_list([award], user)).to eq('You')
+      expect(award_user_list([award], nil)).to eq 'Joe'
     end
 
-    it "displays the current user in front of 0-9 other users" do
-      expect(award_user_list(awards, awards[0].user)).
-        to eq("You, " + awards[1..9].map { |a| a.user.name }.join(', ') + ", and 5 more.")
+    it "truncates lists" do
+      user = build_stubbed(:user, name: 'Jane')
+      awards = Array.new(5, build_stubbed(:award_emoji, user: user))
+
+      expect(award_user_list(awards, nil, limit: 3))
+        .to eq('Jane, Jane, Jane, and 2 more.')
     end
 
-    it "displays the current user in front regardless of position in the list" do
-      expect(award_user_list(awards, awards[12].user)).
-        to eq("You, " + awards[0..8].map { |a| a.user.name }.join(', ') + ", and 5 more.")
+    it "displays the current user in front of other users" do
+      current_user = build_stubbed(:user)
+      my_award = build_stubbed(:award_emoji, user: current_user)
+      award = build_stubbed(:award_emoji, user: build_stubbed(:user, name: 'Jane'))
+      awards = Array.new(5, award).push(my_award)
+
+      expect(award_user_list(awards, current_user, limit: 2)).
+        to eq("You, Jane, and 4 more.")
     end
   end