1 files changed, 51 insertions, 0 deletions
diff --git a/spec/models/preloaders/user_max_access_level_in_groups_preloader_spec.rb b/spec/models/preloaders/user_max_access_level_in_groups_preloader_spec.rb
new file mode 100644
index 00000000000..8144e1ad233
--- /dev/null
+++ b/spec/models/preloaders/user_max_access_level_in_groups_preloader_spec.rb
@@ -0,0 +1,51 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Preloaders::UserMaxAccessLevelInGroupsPreloader do
+  let_it_be(:user) { create(:user) }
+  let_it_be(:group1) { create(:group, :private).tap { |g| g.add_developer(user) } }
+  let_it_be(:group2) { create(:group, :private).tap { |g| g.add_developer(user) } }
+  let_it_be(:group3) { create(:group, :private) }
+
+  let(:max_query_regex) { /SELECT MAX\("members"\."access_level"\).+/ }
+  let(:groups) { [group1, group2, group3] }
+
+  shared_examples 'executes N max member permission queries to the DB' do
+    it 'executes the specified max membership queries' do
+      queries = ActiveRecord::QueryRecorder.new do
+        groups.each { |group| user.can?(:read_group, group) }
+      end
+
+      max_queries = queries.log.grep(max_query_regex)
+
+      expect(max_queries.count).to eq(expected_query_count)
+    end
+  end
+
+  context 'when the preloader is used', :request_store do
+    before do
+      described_class.new(groups, user).execute
+    end
+
+    it_behaves_like 'executes N max member permission queries to the DB' do
+      # Will query all groups where the user is not already a member
+      let(:expected_query_count) { 1 }
+    end
+
+    context 'when user has access but is not a direct member of the group' do
+      let(:groups) { [group1, group2, group3, create(:group, :private, parent: group1)] }
+
+      it_behaves_like 'executes N max member permission queries to the DB' do
+        # One query for group with no access and another one where the user is not a direct member
+        let(:expected_query_count) { 2 }
+      end
+    end
+  end
+
+  context 'when the preloader is not used', :request_store do
+    it_behaves_like 'executes N max member permission queries to the DB' do
+      let(:expected_query_count) { groups.count }
+    end
+  end
+end