1 files changed, 126 insertions, 0 deletions
diff --git a/spec/support_specs/matchers/event_store_spec.rb b/spec/support_specs/matchers/event_store_spec.rb
new file mode 100644
index 00000000000..3614d05fde8
--- /dev/null
+++ b/spec/support_specs/matchers/event_store_spec.rb
@@ -0,0 +1,126 @@
+# frozen_string_literal: true
+
+require 'fast_spec_helper'
+require 'json_schemer'
+
+load File.expand_path('../../../spec/support/matchers/event_store.rb', __dir__)
+
+RSpec.describe 'event store matchers', :aggregate_errors do
+  let(:event_type1) do
+    Class.new(Gitlab::EventStore::Event) do
+      def schema
+        {
+          'type' => 'object',
+          'properties' => {
+            'id' => { 'type' => 'integer' }
+          },
+          'required' => %w[id]
+        }
+      end
+    end
+  end
+
+  let(:event_type2) do
+    Class.new(Gitlab::EventStore::Event) do
+      def schema
+        {
+          'type' => 'object',
+          'properties' => {
+            'id' => { 'type' => 'integer' }
+          },
+          'required' => %w[id]
+        }
+      end
+    end
+  end
+
+  before do
+    stub_const('FakeEventType1', event_type1)
+    stub_const('FakeEventType2', event_type2)
+  end
+
+  def publishing_event(event_type, data = {})
+    ::Gitlab::EventStore.publish(event_type.new(data: data))
+  end
+
+  describe 'publish_event' do
+    it 'requires a block matcher' do
+      matcher = -> { expect(:anything).to publish_event(:anything) } # rubocop: disable RSpec/ExpectActual
+
+      expect(&matcher).to raise_error(
+        ArgumentError,
+        'publish_event matcher only supports block expectation'
+      )
+    end
+
+    it 'validates the event type' do
+      valid_event_type = -> do
+        expect { publishing_event(FakeEventType1, { 'id' => 1 }) }
+          .to publish_event(FakeEventType1).with('id' => 1)
+      end
+
+      expect(&valid_event_type).not_to raise_error
+
+      invalid_event_type = -> do
+        expect { publishing_event(FakeEventType1, { 'id' => 1 }) }
+          .to publish_event(FakeEventType2).with('id' => 1)
+      end
+
+      expect(&invalid_event_type).to raise_error <<~MESSAGE
+        expected FakeEventType2 with {"id"=>1} to be published, but only the following events were published:
+         - FakeEventType1 with {"id"=>1}
+      MESSAGE
+    end
+
+    it 'validates the event data' do
+      missing_data = -> do
+        expect { publishing_event(FakeEventType1, { 'id' => 1 }) }
+          .to publish_event(FakeEventType1)
+      end
+
+      expect(&missing_data).to raise_error <<~MESSAGE
+        expected FakeEventType1 with no data to be published, but only the following events were published:
+         - FakeEventType1 with {"id"=>1}
+      MESSAGE
+
+      different_data = -> do
+        expect { publishing_event(FakeEventType1, { 'id' => 1 }) }
+          .to publish_event(FakeEventType1).with({ 'id' => 2 })
+      end
+
+      expect(&different_data).to raise_error <<~MESSAGE
+        expected FakeEventType1 with {"id"=>2} to be published, but only the following events were published:
+         - FakeEventType1 with {"id"=>1}
+      MESSAGE
+    end
+  end
+
+  describe 'not_publish_event' do
+    it 'requires a block matcher' do
+      matcher = -> { expect(:anything).to not_publish_event(:anything) } # rubocop: disable RSpec/ExpectActual
+
+      expect(&matcher)
+        .to raise_error(ArgumentError, 'not_publish_event matcher only supports block expectation')
+    end
+
+    it 'does not permit .with' do
+      matcher = -> do
+        expect { publishing_event(FakeEventType1, { 'id' => 1 }) }
+          .to not_publish_event(FakeEventType2).with({ 'id' => 1 })
+      end
+
+      expect(&matcher)
+        .to raise_error(ArgumentError, 'not_publish_event does not permit .with to avoid ambiguity')
+    end
+
+    it 'validates the event type' do
+      matcher = -> do
+        expect { publishing_event(FakeEventType1, { 'id' => 1 }) }
+          .to not_publish_event(FakeEventType1)
+      end
+
+      expect(&matcher)
+        .to raise_error('expected FakeEventType1 not to be published')
+    end
+  end
+end