@ethereumjs/vm v5.4.0
London HF Support
This VM release comes with full support for the london hardfork. Please note that the default HF is still set to istanbul. You therefore need to explicitly set the hardfork parameter for instantiating a VM with the london HF activated:
import VM from '@ethereumjs/vm'
import Common from '@ethereumjs/common'
const common = new Common({ chain: 'mainnet', hardfork: 'london' })
const vm = new VM({ common })Support for the following EIPs has been added:
- EIP-1559: Fee market change for ETH 1.0 chain, PR #1148
- EIP-3198: BASEFEE opcode, PR #1148
- EIP-3529: Reduction in refunds, PR #1239
- EIP-3541: Reject new contracts starting with the 0xEF byte, PR #1240
It is also possible to run these EIPs in isolation by instantiating a berlin common and activate selected EIPs with the eips option:
const common = new Common({ chain: 'mainnet', hardfork: 'berlin', eips: [ 3529 ] })EIP-1559: Gas Fee Market
The VM can now run EIP-1559 compatible blocks (introduced with the @ethereumjs/block v3.3.0 release) with VM.runBlock() as well as EIP-1559 txs with type 2 (introduced along the @ethereumjs/tx v3.2.0 release), which can now be passed to VM.runTx() as the tx to be executed. Block and tx validation is happening accordingly and the gas calculation takes the new gas fee market parameters from the block (baseFeePerGas) and the tx(s) (maxFeePerGas and maxPriorityFeePerGas instead of a gasPrice) into account.
EIP-3198: BASEFEE Opcode
There is a new opcode BASEFEE added to the VM, see PR #1148. This opcode is active starting with london and returns the base fee of the current executed upon block.
EIP-3529: Reduction in Refunds
EIP-3529 removes gas refunds for SELFDESTRUCT, and reduces gas refunds for SSTORE, an implementation has been done in PR #1239.
EIP-3541: Reject new Contracts with the 0xEF Byte
There is a new EVM Object Format (EOF) in preparation which will allow to validate contracts at deploy time. This EIP is a preparation for the introduction of this format and disallows contracts which start with the 0xEF byte. Contracts created in the VM via create transaction, CREATE or CREATE2 starting with this byte are now rejected when the EIP is activated and an INVALID_BYTECODE_RESULT is returned as an EVM error with the result, see PR #1240.
StateManager: Preserve State History
This VM release bumps the merkle-patricia-tree dependeny to v4.2.0, which is used as a datastore for the default StateManager implementation. The new MPT version switches to a default behavior to not delete any trie nodes on checkpoint commits, which has implications on the StateManager.commit() function which internally calls the MPT commit. This allows to go back to older trie states by setting a new (old) state root with StateManager.setStateRoot(). The trie state is now guaranteed to still be consistent and complete, which has not been the case before and lead to erraneous behaviour in certain usage scenarios (e.g. reported by HardHat).
See PR #1262
Error Handling: Correct Non-VM Error Propagation
In former versions of the VM non-VM errors happing inside the VM have been (unintentionally) shielded by a try / catch clause in the VM Interpreter class. This lead to existing bugs being hidden and channeled through as VM errors, which made it extremely difficult to trace such bugs down to the root cause. These kind of errors are now properly propagated and therefore lead to a break of the VM control flow. Please note that this might lead to your code breaking if you have got an error in your implementation (this should be a good this though since now this bug can finally be fixed 😀 ).
See PR #1168
Bug Fixes
- StateManager: fixed buffer comparison in
setStateRoot(), PR #1212