Add E2E test for trigger matrix

qa/qa/page/project/pipeline/show.rb

@@ -68,20 +68,30 @@ module QA
             end
           end
 
-          def has_child_pipeline?
-            has_element? :child_pipeline
+          def has_child_pipeline?(title: nil)
+            title ? find_child_pipeline_by_title(title) : has_element?(:child_pipeline)
           end
 
           def has_no_child_pipeline?
-            has_no_element? :child_pipeline
+            has_no_element?(:child_pipeline)
           end
 
           def click_job(job_name)
             click_element(:job_link, Project::Job::Show, text: job_name)
           end
 
-          def expand_child_pipeline
-            within_element(:child_pipeline) do
+          def child_pipelines
+            all_elements(:child_pipeline, minimum: 1)
+          end
+
+          def find_child_pipeline_by_title(title)
+            child_pipelines.find { |pipeline| pipeline[:title].include?(title) }
+          end
+
+          def expand_child_pipeline(title: nil)
+            child_pipeline = title ? find_child_pipeline_by_title(title) : child_pipelines.first
+
+            within_element_by_index(:child_pipeline, child_pipelines.index(child_pipeline)) do
               click_element(:expand_pipeline_button)
             end
           end

qa/qa/specs/features/browser_ui/4_verify/pipeline/trigger_matrix_spec.rb

+# frozen_string_literal: true
+
+require 'faker'
+
+module QA
+  RSpec.describe 'Verify', :runner do
+    describe 'Trigger matrix' do
+      let(:executor) { "qa-runner-#{Faker::Alphanumeric.alphanumeric(8)}" }
+
+      let(:project) do
+        Resource::Project.fabricate_via_api! do |project|
+          project.name = 'project-with-pipeline'
+        end
+      end
+
+      let!(:runner) do
+        Resource::Runner.fabricate! do |runner|
+          runner.project = project
+          runner.name = executor
+          runner.tags = [executor]
+        end
+      end
+
+      before do
+        Flow::Login.sign_in
+        add_ci_files
+        project.visit!
+        Flow::Pipeline.visit_latest_pipeline(pipeline_condition: 'succeeded')
+      end
+
+      after do
+        runner.remove_via_api!
+        project.remove_via_api!
+      end
+
+      it 'creates 2 trigger jobs and passes corresponding matrix variables', testcase: 'https://gitlab.com/gitlab-org/quality/testcases/-/issues/1732' do
+        Page::Project::Pipeline::Show.perform do |parent_pipeline|
+          trigger_title1 = 'deploy: [ovh, monitoring]'
+          trigger_title2 = 'deploy: [ovh, app]'
+
+          aggregate_failures 'Creates two child pipelines' do
+            expect(parent_pipeline).to have_child_pipeline(title: trigger_title1)
+            expect(parent_pipeline).to have_child_pipeline(title: trigger_title2)
+          end
+
+          # Only check output of one of the child pipelines, should be sufficient
+          parent_pipeline.expand_child_pipeline(title: trigger_title1)
+          parent_pipeline.click_job('test_vars')
+        end
+
+        Page::Project::Job::Show.perform do |show|
+          Support::Waiter.wait_until { show.successful? }
+
+          aggregate_failures 'Job output has the correct variables' do
+            expect(show.output).to have_content('ovh')
+            expect(show.output).to have_content('monitoring')
+          end
+        end
+      end
+
+      private
+
+      def add_ci_files
+        Resource::Repository::Commit.fabricate_via_api! do |commit|
+          commit.project = project
+          commit.commit_message = 'Add parent and child pipelines CI files.'
+          commit.add_files(
+            [
+              child_ci_file,
+              parent_ci_file
+            ]
+          )
+        end
+      end
+
+      def parent_ci_file
+        {
+          file_path: '.gitlab-ci.yml',
+          content: <<~YAML
+            test:
+              stage: test
+              script: echo test
+              tags: [#{executor}]
+
+            deploy:
+              stage: deploy
+              trigger:
+                include: child.yml
+              parallel:
+                matrix:
+                  - PROVIDER: ovh
+                    STACK: [monitoring, app]
+
+          YAML
+        }
+      end
+
+      def child_ci_file
+        {
+          file_path: 'child.yml',
+          content: <<~YAML
+            test_vars:
+              script:
+                - echo $PROVIDER
+                - echo $STACK
+              tags: [#{executor}]
+          YAML
+        }
+      end
+    end
+  end
+end