Genesis ProtocolConfig should reject zero blockGasLimit

[Kewe63]

Summary

The genesis ProtocolConfig schema accepts blockGasLimit: 0n, but the runtime contract API requires blockGasLimit to be greater than zero.

This creates an invariant mismatch between genesis configuration validation and later protocol config updates.

A chain can be initialized with a blockGasLimit value that would be rejected by the protocol config contract's mutative API.

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Affected File

scripts/genesis/ProtocolConfig.ts

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Observed Behavior

The genesis schema currently allows:

blockGasLimit: schemaBigInt.min(0n).max(maxUint64)

This means the following value is accepted:

blockGasLimit: 0n

However, the corresponding contract/API-side validation requires blockGasLimit to be greater than zero.

So genesis accepts a value that cannot be set through the normal runtime update path.

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Expected Behavior

The genesis ProtocolConfig schema should enforce the same invariant as the runtime protocol config API.

blockGasLimit should be required to be at least 1:

blockGasLimit: schemaBigInt.min(1n).max(maxUint64)

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Reproduction

I verified this against the current schema with a focused repro.

The repro calls schemaProtocolConfig.parse(...) with:

blockGasLimit: 0n

Observed result:

blockGasLimit=0 ACCEPTED

Expected result:

blockGasLimit=0 should be rejected

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Why This Matters

Genesis configuration should not be able to bypass runtime validation invariants.

If blockGasLimit is zero at genesis, the resulting configuration may be unusable or inconsistent with the contract's own constraints. It also means the same value is treated differently depending on whether it is supplied at genesis or through the runtime update path.

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Suggested Fix

Change the genesis schema bound for blockGasLimit from:

blockGasLimit: schemaBigInt.min(0n).max(maxUint64)

to:

blockGasLimit: schemaBigInt.min(1n).max(maxUint64)

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Potential Regression Test

Add a ProtocolConfig schema test that verifies:

• blockGasLimit: 1n is accepted
• blockGasLimit: 0n is rejected
• blockGasLimit above maxUint64 is rejected