Tag.contains() doesn't work with dynamic registry tags

Here’s a simple test:

1. Write the following code

Tag<Biome> biomeTag = TagFactory.BIOME.create(new Identifier("modid", "test"));
System.out.println(biomeTag.values().size()); //expected "1"

Biome biome1 = BuiltinRegistries.BIOME.get(BiomeKeys.BADLANDS); //in the tag
Biome biome2 = BuiltinRegistries.BIOME.get(BiomeKeys.JUNGLE); //not in the tag
System.out.println(biomeTag.contains(biome1)); //expected "true"
System.out.println(biomeTag.contains(biome2)); //expected "false"

System.out.println(biomeTag.values().get(0)); //expected "minecraft:badlands"
//see Biome's implementation of toString()

1. Put the test.json tag file in the right place

{
  "replace": false,
  "values": [
    "minecraft:badlands"
  ]
}

1. Read the output

[Technici4n]

We need some protection mechanism against this. Perhaps we could throw an error if the wrong registry is used? Clearly this kind of issue will be frequent if we don’t do anything about it.

[LambdAurora]

To be honest, having to use the actual dynamic registry to get the references sounds the intended behavior to me.