Cannot Override LocalContext with Null?

[cccs-ian]

I am running into a scenario where I can't override the local context with a null value. The root data fetcher provides an object as localContext, and an intermediate data fetcher either:

1. Overrides localContext with a different value.
2. Sets localContext to null.

In Scenario 2, the localContext from the root Data Fetcher is carried through the the tertiary data fetcher. I am trying to understand if I am doing something outside the bounds of the framework, or If there is something i am not understanding.

Small example:

Root dataFetcher, sets the context to ThingFilter :

@DgsQuery
public Connection<DataFetcherResult<Thing>> things(
     DataFetchingEnvironment dfe, 
     @InputArgument ThingFilter thingFilter, 
     @InputArgument ConnectionFilter connectionFilter) throws IOException {

var sampleRecords = this.thingRepository.getThings(thingFilter, connectionFilter);

return new SimpleListConnection<>(thingRecords.stream()
                .map(thing-> DataFetcherResult.<Thing>newResult()
                        .data(thing)
                        .localContext(thingFilter)  //Set localContext to ThingFilter
                        .build())
                .collect(Collectors.toList())).get(dfe);

In the intermediate datafetcher, we attempt to wipe the local context with null

@DgsData(field = "tags", parentType = "Thing")
public List<DataFetcherResult<Tag>> tags(DataFetchingEnvironment dfe) {
        //....
	return tagService.getTagsForThing(thing, tagFilter)
			.stream().map(tag -> DataFetcherResult.<Tag>newResult()
					.data(tag)
					.localContext(null) //WIPE LOCAL CONTEXT HERE, Don't want ThingFilter passed down
					.build())
			.collect(Collectors.toList());
}

Tertiary dataFetcher, where dfe.getLocalContext returns ThingFilter again:

    @DgsData(parentType = "Tag", field = "otherThing")
    public List<Thing> tagWithOtherThing(DataFetchingEnvironment dfe) {
        //...
        TagFilter tagFilter = dfe.getLocalContext(); // ClassCastException, i expect tagFilter to simply be null!
        //.....
    }

[cccs-ian]

After doing some reading, I believe this to be the wrong repository for this question, I should head on over to graphql-java :)