fix(protocol): remap item/block state IDs and entity metadata for older Java clients (#2185)

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* fix(protocol): remap item/block state IDs and entity metadata for older Java clients

The server was using reversed ViaVersion mappings (designed for old→new)
to downgrade packets for older clients, which produced ID collisions and
incorrect fallbacks for 26.1-exclusive items and block states.

Changes:
- Replace ViaVersion with ViaBackwards mapping files for item ID and
  block state remapping, which provide the correct new→old direction
  with proper closest-item fallbacks for 26.1-exclusive content
- Fix CSetEntityMetadata to remap ItemStack item IDs per client version,
  matching the version-aware handling already done for inventory packets
  and block state metadata
- Fix TrackedData codegen to resolve Java JSON keys correctly by trying
  both bare names and DATA_-prefixed names, and iterate the union of all
  version keys instead of only the latest (Bedrock) version
- Fix LootCondition::MatchTool to default to false instead of true,
  preventing silk-touch loot table branches from always winning and
  causing ores to drop themselves instead of their correct items

Fixes: block drops invisible on older Java clients
Fixes: leather showing as milk bucket on 1.21.11
Fixes: coal ore dropping coal ore instead of coal
Fixes: 26.1-exclusive blocks showing as wrong blocks on older clients

* fix(codegen): remove #[must_use] from trait impl methods in generated code

* fix(codegen): switch entity, sound and block state remapping to ViaBackwards mappings

---------

Co-authored-by: Missing_Love <42416195+Q2297045667@users.noreply.github.com>

...

This commit is contained in:

Nicolai Van der Storm

2026-05-27 15:22:17 +02:00

committed by GitHub

parent d29e4c18bd

commit 42f6b9ce3f

35 changed files with 17301 additions and 15678 deletions

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