Invert default logging behavior for A/B test

lib/ab_test.rb

@@ -16,9 +16,9 @@ def initialize(queries: [], **)
     end
   end.freeze
 
-  # @param [Proc<String>,Regexp,string,Boolean,nil] should_log Controls whether bucket data for this
-  #                                                            A/B test is logged with specific
-  #                                                            events.
+  # @param [Regexp,#include?,nil] should_log A list of analytics event names for which the A/B test
+  #   bucket assignment should be logged, or a regular expression pattern which is tested against an
+  #   analytics event name when an event is being logged.
   # @yieldparam [ActionDispatch::Request] request
   # @yieldparam [String,nil] service_provider Issuer string for the service provider associated with
   #                                           the current session.
@@ -79,7 +79,7 @@ def include_in_analytics_event?(event_name)
     elsif !should_log.nil?
       raise 'Unexpected value used for should_log'
     else
-      true
+      false
     end
   end
 

spec/lib/ab_test_spec.rb

@@ -171,23 +171,20 @@
     subject(:return_value) { ab_test.include_in_analytics_event?(event_name) }
 
     context 'when should_log is nil' do
-      it 'returns true' do
-        expect(return_value).to eql(true)
-      end
+      it { is_expected.to eql(false) }
     end
 
     context 'when Regexp is used' do
       context 'and it matches' do
         let(:should_log) { /cool/ }
-        it 'returns true' do
-          expect(return_value).to eql(true)
-        end
+
+        it { is_expected.to eql(true) }
       end
+
       context 'and it does not match' do
         let(:should_log) { /not cool/ }
-        it 'returns false' do
-          expect(return_value).to eql(false)
-        end
+
+        it { is_expected.to eql(false) }
       end
     end
 

spec/services/analytics_spec.rb

@@ -154,9 +154,7 @@
               bucket_b: 50,
             },
             should_log:,
-          ) do |user:, **|
-            user.id
-          end,
+          ),
         }
       end
 
@@ -166,28 +164,25 @@
         allow(AbTests).to receive(:all).and_return(ab_tests)
       end
 
-      it 'includes ab_tests in logged event' do
-        expect(ahoy).to receive(:track).with(
-          'Trackable Event',
-          analytics_attributes.merge(
-            ab_tests: {
-              foo_test: {
-                bucket: anything,
-              },
-            },
-          ),
-        )
+      it 'does not include ab_tests in logged event' do
+        expect(ahoy).to receive(:track).with('Trackable Event', analytics_attributes)
 
         analytics.track_event('Trackable Event')
       end
 
-      context 'when should_log says not to' do
-        let(:should_log) { /some other event/ }
+      context 'for an included test' do
+        let(:should_log) { /Trackable/ }
 
-        it 'does not include ab_test in logged event' do
+        it 'includes ab_test bucket detail in logged event' do
           expect(ahoy).to receive(:track).with(
             'Trackable Event',
-            analytics_attributes,
+            analytics_attributes.merge(
+              ab_tests: {
+                foo_test: {
+                  bucket: be_in([:bucket_a, :bucket_b]),
+                },
+              },
+            ),
           )
 
           analytics.track_event('Trackable Event')