header method in V4 PactBuilder splits up values

[huehnerlady]

Hi,
I am currently trying to move to V4 pacts.

Currently I have this pact, which works

@Pact(consumer = CONSUMER, provider = PROVIDER)
RequestResponsePact provider(PactDslWithProvider builder) {
  return builder
      .uponReceiving("get")
      .method("GET")
      .headers("accept", "application/json, application/*+json")
      .path("/test")
      .willRespondWith()
      .status(200)
      .toPact()
}

I migrated it to look like this:

@Pact(consumer = CONSUMER, provider = PROVIDER)
V4Pact provider(PactBuilder builder) {
  return builder
      .expectsToReceiveHttpInteraction("get") { httpBuilder ->
        httpBuilder
            .withRequest { httpRequestBuilder ->
              httpRequestBuilder
                  .path("/test")
                  .method("GET")
                  .headers("accept", "application/json, application/*+json")
            }
            .willRespondWith { httpResponseBuilder ->
              httpResponseBuilder.status(200)
            }
      }
      .toPact()
}

but now I get this error message from Pact:

2025-01-16 11:41:50,475 [HTTP-Dispatcher] ERROR  a.c.d.p.c.BaseMockServer$Companion - PartialRequestMatch: get:
    Expected header 'accept' to have value 'application/json' but was 'application/json, application/*+json'
    Expected header 'accept' to have value 'application/*+json' but was ''

I am very confused as the signature of the method headers I am using shows it as a value:String. I also tried the header method, but I still get the same error.

After asking in Slack what I can do I was asked to raise it as a potential bug.