fix: remove omitEmptyArray default in Ec2Service constructor

design/aws-ecs/aws-ecs-tagging-support.md

@@ -171,7 +171,7 @@ export class Ec2Service extends BaseService implements IEc2Service, elb.ILoadBal
     {
       cluster: props.cluster.clusterName,
       taskDefinition: props.taskDefinition.taskDefinitionArn,
-      placementConstraints: Lazy.anyValue({ produce: () => this.constraints }, { omitEmptyArray: true }),
+      placementConstraints: Lazy.anyValue({ produce: () => this.constraints }),
       placementStrategies: Lazy.anyValue({ produce: () => this.strategies }, { omitEmptyArray: true }),
       schedulingStrategy: props.daemon ? 'DAEMON' : 'REPLICA',
     }, props.taskDefinition);

packages/aws-cdk-lib/aws-ecs/lib/ec2/ec2-service.ts

@@ -179,7 +179,7 @@ export class Ec2Service extends BaseService implements IEc2Service {
     {
       cluster: props.cluster.clusterName,
       taskDefinition: props.deploymentController?.type === DeploymentControllerType.EXTERNAL ? undefined : props.taskDefinition.taskDefinitionArn,
-      placementConstraints: Lazy.any({ produce: () => this.constraints }, { omitEmptyArray: true }),
+      placementConstraints: Lazy.any({ produce: () => this.constraints }),
       placementStrategies: Lazy.any({ produce: () => this.strategies }, { omitEmptyArray: true }),
       schedulingStrategy: props.daemon ? 'DAEMON' : 'REPLICA',
     }, props.taskDefinition);

packages/aws-cdk-lib/aws-ecs/test/ec2/ec2-service.test.ts

@@ -1853,6 +1853,32 @@ describe('ec2 service', () => {
       });
     });
 
+    test('with an empty list in placement constraints', () => {
+      // GIVEN
+      const stack = new cdk.Stack();
+      const vpc = new ec2.Vpc(stack, 'MyVpc', {});
+      const cluster = new ecs.Cluster(stack, 'EcsCluster', { vpc });
+      addDefaultCapacityProvider(cluster, stack, vpc);
+      const taskDefinition = new ecs.Ec2TaskDefinition(stack, 'Ec2TaskDef');
+
+      taskDefinition.addContainer('web', {
+        image: ecs.ContainerImage.fromRegistry('amazon/amazon-ecs-sample'),
+        memoryLimitMiB: 512,
+      });
+
+      new ecs.Ec2Service(stack, 'Ec2Service', {
+        cluster,
+        taskDefinition,
+        placementConstraints: [],
+      });
+
+      // THEN
+      Template.fromStack(stack).hasResourceProperties('AWS::ECS::Service', {
+        PlacementConstraints: Match.arrayEquals([]),
+      });
+
+    });
+
     testDeprecated('with both propagateTags and propagateTaskTagsFrom defined', () => {
       // GIVEN
       const stack = new cdk.Stack();