Add unit tests for FactoryBot::CallbacksObserver

spec/factory_bot/callbacks_observer_spec.rb

@@ -0,0 +1,92 @@
+describe FactoryBot::CallbacksObserver do
+  it "runs callbacks matching the given name" do
+    evaluator = double("evaluator")
+    callback = double("callback", name: :after_create)
+    allow(callback).to receive(:run)
+    observer = FactoryBot::CallbacksObserver.new([callback], evaluator)
+    instance = double("instance")
+
+    observer.update(:after_create, instance)
+
+    expect(callback).to have_received(:run).with(instance, evaluator)
+  end
+
+  it "does not run callbacks that do not match the given name" do
+    evaluator = double("evaluator")
+    callback = double("callback", name: :after_build)
+    allow(callback).to receive(:run)
+    observer = FactoryBot::CallbacksObserver.new([callback], evaluator)
+    instance = double("instance")
+
+    observer.update(:after_create, instance)
+
+    expect(callback).not_to have_received(:run)
+  end
+
+  it "runs multiple callbacks matching the given name" do
+    evaluator = double("evaluator")
+    callback1 = double("callback1", name: :after_create)
+    callback2 = double("callback2", name: :after_create)
+    allow(callback1).to receive(:run)
+    allow(callback2).to receive(:run)
+    observer = FactoryBot::CallbacksObserver.new([callback1, callback2], evaluator)
+    instance = double("instance")
+
+    observer.update(:after_create, instance)
+
+    expect(callback1).to have_received(:run).with(instance, evaluator)
+    expect(callback2).to have_received(:run).with(instance, evaluator)
+  end
+
+  it "does not run the same callback twice for the same instance" do
+    evaluator = double("evaluator")
+    callback = double("callback", name: :after_create)
+    allow(callback).to receive(:run)
+    observer = FactoryBot::CallbacksObserver.new([callback], evaluator)
+    instance = double("instance")
+
+    observer.update(:after_create, instance)
+    observer.update(:after_create, instance)
+
+    expect(callback).to have_received(:run).once
+  end
+
+  it "runs the same callback for different instances" do
+    evaluator = double("evaluator")
+    callback = double("callback", name: :after_create)
+    allow(callback).to receive(:run)
+    observer = FactoryBot::CallbacksObserver.new([callback], evaluator)
+    instance1 = double("instance1")
+    instance2 = double("instance2")
+
+    observer.update(:after_create, instance1)
+    observer.update(:after_create, instance2)
+
+    expect(callback).to have_received(:run).with(instance1, evaluator)
+    expect(callback).to have_received(:run).with(instance2, evaluator)
+  end
+
+  it "runs different callbacks for the same instance" do
+    evaluator = double("evaluator")
+    callback1 = double("callback1", name: :after_create)
+    callback2 = double("callback2", name: :after_build)
+    allow(callback1).to receive(:run)
+    allow(callback2).to receive(:run)
+    observer = FactoryBot::CallbacksObserver.new([callback1, callback2], evaluator)
+    instance = double("instance")
+
+    observer.update(:after_create, instance)
+    observer.update(:after_build, instance)
+
+    expect(callback1).to have_received(:run).with(instance, evaluator)
+    expect(callback2).to have_received(:run).with(instance, evaluator)
+  end
+
+  it "handles an empty callback list" do
+    evaluator = double("evaluator")
+    observer = FactoryBot::CallbacksObserver.new([], evaluator)
+    instance = double("instance")
+
+    expect { observer.update(:after_create, instance) }.not_to raise_error
+  end
+end