1 files changed, 46 insertions, 0 deletions
diff --git a/spec/lib/gitlab/background_migration/backfill_ci_project_mirrors_spec.rb b/spec/lib/gitlab/background_migration/backfill_ci_project_mirrors_spec.rb
new file mode 100644
index 00000000000..4eec83879e3
--- /dev/null
+++ b/spec/lib/gitlab/background_migration/backfill_ci_project_mirrors_spec.rb
@@ -0,0 +1,46 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Gitlab::BackgroundMigration::BackfillCiProjectMirrors, :migration, schema: 20211208122201 do
+  let(:namespaces) { table(:namespaces) }
+  let(:projects) { table(:projects) }
+  let(:ci_project_mirrors) { table(:ci_project_mirrors) }
+
+  subject { described_class.new }
+
+  describe '#perform' do
+    it 'creates ci_project_mirrors for all projects in range' do
+      namespaces.create!(id: 10, name: 'namespace1', path: 'namespace1')
+      projects.create!(id: 5, namespace_id: 10, name: 'test1', path: 'test1')
+      projects.create!(id: 7, namespace_id: 10, name: 'test2', path: 'test2')
+      projects.create!(id: 8, namespace_id: 10, name: 'test3', path: 'test3')
+
+      subject.perform(5, 7)
+
+      expect(ci_project_mirrors.all).to contain_exactly(
+        an_object_having_attributes(project_id: 5, namespace_id: 10),
+        an_object_having_attributes(project_id: 7, namespace_id: 10)
+      )
+    end
+
+    it 'handles existing ci_project_mirrors gracefully' do
+      namespaces.create!(id: 10, name: 'namespace1', path: 'namespace1')
+      namespaces.create!(id: 11, name: 'namespace2', path: 'namespace2', parent_id: 10)
+      projects.create!(id: 5, namespace_id: 10, name: 'test1', path: 'test1')
+      projects.create!(id: 7, namespace_id: 11, name: 'test2', path: 'test2')
+      projects.create!(id: 8, namespace_id: 11, name: 'test3', path: 'test3')
+
+      # Simulate a situation where a user has had a chance to move a project to another namespace
+      # before the background migration has had a chance to run
+      ci_project_mirrors.create!(project_id: 7, namespace_id: 10)
+
+      subject.perform(5, 7)
+
+      expect(ci_project_mirrors.all).to contain_exactly(
+        an_object_having_attributes(project_id: 5, namespace_id: 10),
+        an_object_having_attributes(project_id: 7, namespace_id: 10)
+      )
+    end
+  end
+end