From 216cea1e277530d39eefddbfccb519d2eca72b8b Mon Sep 17 00:00:00 2001
From: Matt Jankowski <matt@jankowski.online>
Date: Tue, 12 Mar 2024 04:38:32 -0400
Subject: [PATCH] Fix incorrect frequency value in `FriendsOfFriendsSource`
 data (#29550)

---
 .../friends_of_friends_source.rb              | 12 +++++---
 .../friends_of_friends_source_spec.rb         | 30 +++++++++++++++----
 2 files changed, 32 insertions(+), 10 deletions(-)

diff --git a/app/models/account_suggestions/friends_of_friends_source.rb b/app/models/account_suggestions/friends_of_friends_source.rb
index 0c95d21a3e9..b4f549bf314 100644
--- a/app/models/account_suggestions/friends_of_friends_source.rb
+++ b/app/models/account_suggestions/friends_of_friends_source.rb
@@ -2,15 +2,19 @@
 
 class AccountSuggestions::FriendsOfFriendsSource < AccountSuggestions::Source
   def get(account, limit: DEFAULT_LIMIT)
+    source_query(account, limit: limit)
+      .map { |id, _frequency, _followers_count| [id, key] }
+  end
+
+  def source_query(account, limit: DEFAULT_LIMIT)
     first_degree = account.following.where.not(hide_collections: true).select(:id).reorder(nil)
     base_account_scope(account)
       .joins(:account_stat)
-      .where(id: Follow.where(account_id: first_degree).select(:target_account_id))
+      .joins(:passive_relationships).where(passive_relationships: { account_id: first_degree })
       .group('accounts.id, account_stats.id')
-      .reorder('frequency DESC, followers_count DESC')
+      .reorder(frequency: :desc, followers_count: :desc)
       .limit(limit)
-      .pluck(Arel.sql('accounts.id, COUNT(*) AS frequency'))
-      .map { |id, _frequency| [id, key] }
+      .pluck(Arel.sql('accounts.id, COUNT(*) AS frequency, followers_count'))
   end
 
   private
diff --git a/spec/models/account_suggestions/friends_of_friends_source_spec.rb b/spec/models/account_suggestions/friends_of_friends_source_spec.rb
index 56a974add54..d7915985f8c 100644
--- a/spec/models/account_suggestions/friends_of_friends_source_spec.rb
+++ b/spec/models/account_suggestions/friends_of_friends_source_spec.rb
@@ -11,9 +11,9 @@ RSpec.describe AccountSuggestions::FriendsOfFriendsSource do
     let!(:eve) { Fabricate(:account, discoverable: true, hide_collections: false) }
     let!(:mallory) { Fabricate(:account, discoverable: false, hide_collections: false) }
     let!(:eugen) { Fabricate(:account, discoverable: true, hide_collections: false) }
+    let!(:neil) { Fabricate(:account, discoverable: true, hide_collections: false) }
     let!(:john) { Fabricate(:account, discoverable: true, hide_collections: false) }
     let!(:jerk) { Fabricate(:account, discoverable: true, hide_collections: false) }
-    let!(:neil) { Fabricate(:account, discoverable: true, hide_collections: false) }
     let!(:larry) { Fabricate(:account, discoverable: true, hide_collections: false) }
 
     context 'with follows and blocks' do
@@ -70,13 +70,31 @@ RSpec.describe AccountSuggestions::FriendsOfFriendsSource do
       end
 
       it 'returns eligible accounts in the expected order' do
-        expect(subject.get(bob)).to eq [
-          [eugen.id, :friends_of_friends], # followed by 2 friends, 3 followers total
-          [john.id, :friends_of_friends], # followed by 2 friends, 2 followers total
-          [neil.id, :friends_of_friends], # followed by 1 friend, 2 followers total
-          [jerk.id, :friends_of_friends], # followed by 1 friend, 1 follower total
+        expect(subject.get(bob)).to eq expected_results
+      end
+
+      it 'contains correct underlying source data' do
+        expect(source_query_values)
+          .to contain_exactly(
+            [eugen.id, 2, 3], # Followed by 2 friends of bob (eve, mallory), 3 followers total (breaks tie)
+            [john.id, 2, 2],  # Followed by 2 friends of bob (eve, mallory), 2 followers total
+            [neil.id, 1, 2],  # Followed by 1 friends of bob (mallory), 2 followers total (breaks tie)
+            [jerk.id, 1, 1]   # Followed by 1 friends of bob (eve), 1 followers total
+          )
+      end
+
+      def expected_results
+        [
+          [eugen.id, :friends_of_friends],
+          [john.id, :friends_of_friends],
+          [neil.id, :friends_of_friends],
+          [jerk.id, :friends_of_friends],
         ]
       end
+
+      def source_query_values
+        subject.source_query(bob).to_a
+      end
     end
   end
 end