Fix ClassCastException in BlockCable when sapling grows nearby

[Copilot]

BlockCable.updateShape and getCloneItemStack were unconditionally casting LevelAccessor/LevelReader to Level. During world feature placement (e.g. sapling → tree growth), Minecraft invokes updateShape with a lightweight accessor that is not a Level, causing a ClassCastException crash.

Changes

• updateShape: Wrap NetworkHelpers.onElementProviderBlockNeighborChange in an instanceof Level guard — silently skip the neighbor-change notification when the accessor isn't a full Level.
• getCloneItemStack: Combine the existing rayTraceResult != null check with world instanceof Level to avoid the unsafe cast when called with a plain LevelReader.

// updateShape — before
NetworkHelpers.onElementProviderBlockNeighborChange((Level) worldIn, currentPos, facingState.getBlock(), facing, facingPos);

// after
if (worldIn instanceof Level level) {
    NetworkHelpers.onElementProviderBlockNeighborChange(level, currentPos, facingState.getBlock(), facing, facingPos);
}

// getCloneItemStack — before
if (rayTraceResult != null) {
    return rayTraceResult.getComponent().getCloneItemStack((Level) world, blockPos);
}

// after
if (rayTraceResult != null && world instanceof Level level) {
    return rayTraceResult.getComponent().getCloneItemStack(level, blockPos);
}

Original prompt

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This section details on the original issue you should resolve

<issue_title>Crash with sapling growing triggering BlockCable.updateShape</issue_title>
<issue_description>

Issue type:

• 🐛 Bug

---

Short description:

Our ATM10 server keeps crashing, seemingly at random. After inspecting the crash report, we narrowed it down to when saplings (in our case oak) were growing near logic cables. Attempts to forcibly reproduce it were unsuccessful.

Steps to reproduce the problem:

1. Plant oak sapling in close proximity to logic cable
2. Hope it crashes after the sapling grows.

Expected behaviour:

N/A

---

Versions:

• This mod: 1.30.5
• Minecraft: 1.21.1
• Mod loader version: NeoForge 21.1.219

Log file:

crash-2026-03-03_20.17.53-server.txt

</issue_description>

<agent_instructions>The problem here is that we're unsafely casting to (Level) in BlockCable. Could you wrap these in an instanceof check? There should be two places in BlockCable where this happens, and needs a safety check.</agent_instructions>

Comments on the Issue (you are @copilot in this section)

@rubensworks

Thanks for reporting!

• Fixes Crash with sapling growing triggering BlockCable.updateShape #1622

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[coveralls]

coverage: 45.725% (-0.01%) from 45.735%
when pulling 464b62a on copilot/fix-sapling-growth-crash
into 67ec6fb on master-1.21-lts.