very rough idea with storing test retry callback in Thread.current to…

… make it accessible in Minitest hooks

lib/datadog/ci/contrib/minitest/runner.rb

@@ -28,6 +28,19 @@ def init_plugins(*args)
               test_visibility_component.start_test_module(Ext::FRAMEWORK)
             end
 
+            def run_one_method(klass, method_name)
+              return super unless datadog_configuration[:enabled]
+
+              result = nil
+              # retries here
+              test_retries_component.with_retries do |test_finished_callback|
+                Thread.current[:__dd_retry_callback] = test_finished_callback
+
+                result = super
+              end
+              result
+            end
+
             private
 
             def datadog_configuration
@@ -37,6 +50,10 @@ def datadog_configuration
             def test_visibility_component
               Datadog.send(:components).test_visibility
             end
+
+            def test_retries_component
+              Datadog.send(:components).test_retries
+            end
           end
         end
       end

lib/datadog/ci/contrib/minitest/test.rb

@@ -50,7 +50,7 @@ def after_teardown
               test_span = test_visibility_component.active_test
               return super unless test_span
 
-              finish_with_result(test_span, result_code)
+              finish_with_result(test_span, result_code, Thread.current[:__dd_retry_callback])
               if Helpers.parallel?(self.class)
                 finish_with_result(test_span.test_suite, result_code)
               end
@@ -60,7 +60,7 @@ def after_teardown
 
             private
 
-            def finish_with_result(span, result_code)
+            def finish_with_result(span, result_code, callback = nil)
               return unless span
 
               case result_code
@@ -71,6 +71,9 @@ def finish_with_result(span, result_code)
               when "S"
                 span.skipped!(reason: failure.message)
               end
+
+              callback.call(span) if callback
+
               span.finish
             end
 

spec/datadog/ci/contrib/minitest/instrumentation_spec.rb

@@ -948,4 +948,47 @@ def test_with_background_thread
       )
     end
   end
+
+  context "with flaky test and test retries enabled" do
+    include_context "CI mode activated" do
+      let(:integration_name) { :minitest }
+
+      let(:flaky_test_retries_enabled) { true }
+    end
+
+    before do
+      Minitest.run([])
+    end
+
+    before(:context) do
+      Thread.current[:dd_coverage_collector] = nil
+
+      Minitest::Runnable.reset
+
+      require_relative "helpers/addition_helper"
+      class SomeTestWithThreads < Minitest::Test
+        def test_with_background_thread
+          # add thread to test that code coverage is collected
+          t = Thread.new do
+            AdditionHelper.add(1, 2)
+          end
+          t.join
+          assert true
+        end
+      end
+    end
+
+    it "does not cover the background thread" do
+      skip if PlatformHelpers.jruby?
+
+      expect(test_spans).to have(1).item
+      expect(coverage_events).to have(1).item
+
+      # expect that background thread is not covered
+      cov_event = find_coverage_for_test(first_test_span)
+      expect(cov_event.coverage.keys).not_to include(
+        absolute_path("helpers/addition_helper.rb")
+      )
+    end
+  end
 end