auto-merge-service-conflict

Id

@azure-tools/typespec-client-generator-core/auto-merge-service-conflict

Severity: error

This diagnostic is issued when a parent client uses autoMergeService and a nested client also specifies its own service configuration.

Impact

• Area: Multi-service client hierarchy. Blocks an auto-merged parent client from also containing a nested client with its own explicit service binding.
• Not affected: The underlying service namespaces and routes remain valid independently.

❌ Incorrect Usage

@service
namespace ServiceA {
  @route("/aTest")
  op opA(): void;
}

@service
namespace ServiceB {
  @route("/bTest")
  op opB(): void;
}

@client({
  name: "ParentClient",
  service: [ServiceA, ServiceB],
  autoMergeService: true,
})
namespace ParentClient {
  @client({
    name: "ChildClient",
    service: ServiceA, // child service conflicts with the parent's `autoMergeService`
  })
  namespace Child {

  }
}

Diagnostic Message

TCGC reports:

Auto-merging service client must be empty.

✅ How to Fix

Leave the nested client’s service option unset so it inherits from the parent, or remove the parent autoMergeService setup.

@service
namespace ServiceA {
  @route("/aTest")
  op opA(): void;
}

@service
namespace ServiceB {
  @route("/bTest")
  op opB(): void;
}

@client({
  name: "ParentClient",
  service: [ServiceA, ServiceB],
  autoMergeService: true,
})
namespace ParentClient {
  @client({
    name: "ChildClient",
  })
  namespace Child {

  }
}