1 files changed, 83 insertions, 0 deletions
diff --git a/spec/models/concerns/loose_foreign_key_spec.rb b/spec/models/concerns/loose_foreign_key_spec.rb
new file mode 100644
index 00000000000..ce5e33261a9
--- /dev/null
+++ b/spec/models/concerns/loose_foreign_key_spec.rb
@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe LooseForeignKey do
+  let(:project_klass) do
+    Class.new(ApplicationRecord) do
+      include LooseForeignKey
+
+      self.table_name = 'projects'
+
+      loose_foreign_key :issues, :project_id, on_delete: :async_delete, gitlab_schema: :gitlab_main
+      loose_foreign_key 'merge_requests', 'project_id', 'on_delete' => 'async_nullify', 'gitlab_schema' => :gitlab_main
+    end
+  end
+
+  it 'exposes the loose foreign key definitions' do
+    definitions = project_klass.loose_foreign_key_definitions
+
+    tables = definitions.map(&:to_table)
+    expect(tables).to eq(%w[issues merge_requests])
+  end
+
+  it 'casts strings to symbol' do
+    definition = project_klass.loose_foreign_key_definitions.last
+
+    expect(definition.from_table).to eq('projects')
+    expect(definition.to_table).to eq('merge_requests')
+    expect(definition.column).to eq('project_id')
+    expect(definition.on_delete).to eq(:async_nullify)
+    expect(definition.options[:gitlab_schema]).to eq(:gitlab_main)
+  end
+
+  context 'validation' do
+    context 'on_delete validation' do
+      let(:invalid_class) do
+        Class.new(ApplicationRecord) do
+          include LooseForeignKey
+
+          self.table_name = 'projects'
+
+          loose_foreign_key :issues, :project_id, on_delete: :async_delete, gitlab_schema: :gitlab_main
+          loose_foreign_key :merge_requests, :project_id, on_delete: :async_nullify, gitlab_schema: :gitlab_main
+          loose_foreign_key :merge_requests, :project_id, on_delete: :destroy, gitlab_schema: :gitlab_main
+        end
+      end
+
+      it 'raises error when invalid `on_delete` option was given' do
+        expect { invalid_class }.to raise_error /Invalid on_delete option given: destroy/
+      end
+    end
+
+    context 'gitlab_schema validation' do
+      let(:invalid_class) do
+        Class.new(ApplicationRecord) do
+          include LooseForeignKey
+
+          self.table_name = 'projects'
+
+          loose_foreign_key :merge_requests, :project_id, on_delete: :async_nullify, gitlab_schema: :unknown
+        end
+      end
+
+      it 'raises error when invalid `gitlab_schema` option was given' do
+        expect { invalid_class }.to raise_error /Invalid gitlab_schema option given: unknown/
+      end
+    end
+
+    context 'inheritance validation' do
+      let(:inherited_project_class) do
+        Class.new(Project) do
+          include LooseForeignKey
+
+          loose_foreign_key :issues, :project_id, on_delete: :async_delete, gitlab_schema: :gitlab_main
+        end
+      end
+
+      it 'raises error when loose_foreign_key is defined in a child ActiveRecord model' do
+        expect { inherited_project_class }.to raise_error /Please define the loose_foreign_key on the Project class/
+      end
+    end
+  end
+end