Track transition error on concurrent bridge update

app/services/ci/create_cross_project_pipeline_service.rb

@@ -6,6 +6,7 @@ module Ci
     include Gitlab::Utils::StrongMemoize
 
     DuplicateDownstreamPipelineError = Class.new(StandardError)
+    InvalidBridgeTransition = Class.new(StandardError)
 
     def execute(bridge)
       @bridge = bridge
@@ -52,6 +53,11 @@ module Ci
           subject.drop!(:downstream_pipeline_creation_failed)
         end
       end
+    rescue StateMachines::InvalidTransition => e
+      Gitlab::ErrorTracking.track_exception(
+        InvalidBridgeTransition.new(e.message),
+        bridge_id: bridge.id,
+        downstream_pipeline_id: pipeline.id)
     end
 
     def ensure_preconditions!(target_ref)

spec/services/ci/create_cross_project_pipeline_service_spec.rb

@@ -362,6 +362,26 @@ describe Ci::CreateCrossProjectPipelineService, '#execute' do
       end
     end
 
+    context 'when bridge job status update raises state machine errors' do
+      let(:stub_config) { false }
+
+      before do
+        stub_ci_pipeline_yaml_file(YAML.dump(invalid: { yaml: 'error' }))
+        bridge.drop!
+      end
+
+      it 'tracks the exception' do
+        expect(Gitlab::ErrorTracking)
+          .to receive(:track_exception)
+          .with(
+            instance_of(Ci::CreateCrossProjectPipelineService::InvalidBridgeTransition),
+            bridge_id: bridge.id,
+            downstream_pipeline_id: kind_of(Numeric))
+
+        service.execute(bridge)
+      end
+    end
+
     context 'when bridge job has YAML variables defined' do
       before do
         bridge.yaml_variables = [{ key: 'BRIDGE', value: 'var', public: true }]