Fix DeferredHolderCommon delegates not being references on Forge

[rubensworks]

Background

Two earlier fixes made DeferredHolderCommon behave for other mods and for serialization:

• 9dacc1a "Fix DeferredHolderCommon not handling delegates correctly": added IHolderCommon#getDelegate plus the MixinRegistry/MixinHolder mixins, so that Registry#safeCastToReference can unwrap a DeferredHolderCommon into the Holder.Reference it wraps. NeoForge does this natively through IHolderExtension#getDelegate; Fabric and Forge get it from the mixins.
• e199d51 "Fix Mixin breaking other DeferredHolders": removed the error branch from that mixin, so holders of other mods fall through to the loader's own implementation.

Both were applied to all three loaders at the time, so there is nothing left to port as such. The delegate fix does not take effect on Forge though, because of an older Forge-only addition:

• f3a4fe8 "Make DeferredHolderCommon work with IForgeRegistry" added DeferredHolderCommon.BIND_OVERRIDE, which Forge installs to resolve entries from IForgeRegistrys. It is consulted before the regular registry and binds to Holder.direct(value).

Since a Holder.Direct is not a Holder.Reference, the delegate never satisfies safeCastToReference, and Forge keeps hitting exactly the failure the delegate fix was meant to remove. Forge wraps many vanilla registries (particle_type, menu, block, item, block_entity_type, ...), so the override is hit for most entries. Reproduced with the new game tests on Forge before this change:

Expected a Holder.Reference delegate, but got Direct{org.cyclops.cyclopscore.client.particle.ParticleBlurConfig$1@629059a9}
Expected a successful encoding, but got DataResult.Error['Unregistered holder in ResourceKey[minecraft:root / minecraft:particle_type]: DeferredHolderCommon{ResourceKey[minecraft:particle_type / cyclopscore:blur]}']

Changes

• DeferredHolderCommon#bind consults the regular registry first and only falls back to BIND_OVERRIDE for entries that are not in a regular registry. This matches NeoForge's upstream DeferredHolder, which binds through the registry only, and yields the canonical Holder.Reference.
• The Forge BIND_OVERRIDE prefers ForgeRegistry#getDelegate, which returns a Holder.Reference, and only falls back to Holder.direct for registries without a wrapper (those are not in the root registry, so they cannot be serialized through a registry codec anyway).
• Added DeferredHolderCommonTest game tests, registered on all three loaders, asserting that the delegate is a reference and that the holder encodes through a registry holder codec.

Testing

• ./gradlew build passes.
• ./gradlew runGameTestServer passes on Forge, NeoForge and Fabric. Before the change, the two new tests failed on Forge and passed on NeoForge and Fabric.

🤖 Generated with Claude Code

https://claude.ai/code/session_01WyxzX1DGvXj5nV4zew3V8u

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Generated by Claude Code

[sonarqubecloud]

Quality Gate failed

Failed conditions
3.3% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud

[coveralls]

coverage: 31.415% (+0.2%) from 31.187% — claude/epic-noether-3ue5cn into master-26-lts