1 files changed, 58 insertions, 3 deletions

diff --git a/spec/support/matchers/event_store.rb b/spec/support/matchers/event_store.rb
index 4ecb924b3ed..582ea202187 100644
--- a/spec/support/matchers/event_store.rb
+++ b/spec/support/matchers/event_store.rb
@@ -6,7 +6,7 @@ RSpec::Matchers.define :publish_event do |expected_event_class|
   supports_block_expectations
 
   match do |proc|
-    raise ArgumentError, 'This matcher only supports block expectation' unless proc.respond_to?(:call)
+    raise ArgumentError, 'publish_event matcher only supports block expectation' unless proc.respond_to?(:call)
 
     @events ||= []
 
@@ -22,6 +22,8 @@ RSpec::Matchers.define :publish_event do |expected_event_class|
   end
 
   def match_data?(actual, expected)
+    return if actual.blank? || expected.blank?
+
     values_match?(actual.keys, expected.keys) &&
       actual.keys.all? do |key|
         values_match?(expected[key], actual[key])
@@ -33,11 +35,20 @@ RSpec::Matchers.define :publish_event do |expected_event_class|
   end
 
   failure_message do
-    "expected #{expected_event_class} with #{@expected_data} to be published, but got #{@events}"
+    message = "expected #{expected_event_class} with #{@expected_data || 'no data'} to be published"
+
+    if @events.present?
+      <<~MESSAGE
+      #{message}, but only the following events were published:
+      #{events_list}
+      MESSAGE
+    else
+      "#{message}, but no events were published."
+    end
   end
 
   match_when_negated do |proc|
-    raise ArgumentError, 'This matcher only supports block expectation' unless proc.respond_to?(:call)
+    raise ArgumentError, 'publish_event matcher only supports block expectation' unless proc.respond_to?(:call)
 
     allow(Gitlab::EventStore).to receive(:publish)
 
@@ -45,4 +56,48 @@ RSpec::Matchers.define :publish_event do |expected_event_class|
 
     expect(Gitlab::EventStore).not_to have_received(:publish).with(instance_of(expected_event_class))
   end
+
+  def events_list
+    @events.map do |event|
+      " - #{event.class.name} with #{event.data}"
+    end.join("\n")
+  end
+end
+
+# not_publish_event enables multiple assertions on a single block, for example:
+#     expect { Model.create(invalid: :attribute) }
+#       .to not_change(Model, :count)
+#       .and not_publish_event(ModelCreated)
+RSpec::Matchers.define :not_publish_event do |expected_event_class|
+  include RSpec::Matchers::Composable
+
+  supports_block_expectations
+
+  match do |proc|
+    raise ArgumentError, 'not_publish_event matcher only supports block expectation' unless proc.respond_to?(:call)
+
+    @events ||= []
+
+    allow(Gitlab::EventStore).to receive(:publish) do |published_event|
+      @events << published_event
+    end
+
+    proc.call
+
+    @events.none? do |event|
+      event.instance_of?(expected_event_class)
+    end
+  end
+
+  failure_message do
+    "expected #{expected_event_class} not to be published"
+  end
+
+  chain :with do |_| # rubocop: disable Lint/UnreachableLoop
+    raise ArgumentError, 'not_publish_event does not permit .with to avoid ambiguity'
+  end
+
+  match_when_negated do |proc|
+    raise ArgumentError, 'not_publish_event matcher does not support negation. Use `expect {}.to publish_event` instead'
+  end
 end